| T.R | Title | User | Personal
Name | Date | Lines |
|---|
| 770.1 | Extreme Ultraviolet Explorer Shipped to Florida
| PRAGMA::GRIFFIN | Dave Griffin | Tue Jan 28 1992 23:07 | 46 |
| Dolores Beasley
Office of Public Affairs
Release: 92-12 January 27, 1992
NASA's Extreme Ultraviolet Explorer (EUVE), a satellite
designed to observe one of the least-studied portions of the
spectrum, the extreme ultraviolet, is leaving Maryland today for
Cape Canaveral Air Force Station, Fla., where it is scheduled to
launch in May. The spacecraft has undergone assembly,
integration and environmental testing at Goddard Space Flight
Center, Md., since April 1991.
The EUVE consists of an Explorer Platform spacecraft and a
science payload module. The Explorer Platform is scheduled to
leave Goddard by truck today and arrive at Cape Canaveral Air
Force Station January 28. The science payload module was taken
to Andrews Air Force Base, Md., on Sunday, January 26. The
module will be flown from Andrews on a C5-A airplane to Kennedy
Space Center, Fla., today. The satellite's solar arrays were
shipped to Cape Canaveral in December.
The mating of the science payload module to the Explorer
Platform is scheduled to occur at Cape Canaveral on Friday,
January 31, followed by performance testing that starts on
February 3.
The scientific mission of EUVE consists of two parts; a sky
survey to determine the distribution of extreme ultraviolet
sources within and outside the Milky Way; followed by
spectroscopic studies of selected objects to investigate their
physical properties and chemical compositions.
The satellite will carry three scanning telescopes and one
deep survey/spectrometer telescope developed by scientists at the
University of California at Berkeley. The telescopes are mounted
in a payload module that is attached to the Explorer Platform
spacecraft designed and built by Fairchild Space Company,
Germantown, Md., under Goddard management.
The Goddard Space Flight Center manages the Extreme
Ultraviolet Explorer project for NASA's Office of Space Science
and Applications, Astrophysics Division.
|
| 770.2 | EUVE Newsletter | VERGA::KLAES | All the Universe, or nothing! | Fri Mar 06 1992 14:30 | 101 |
| Article: 451
From: marchant@ssl.berkeley.edu (Will Marchant)
Newsgroups: sci.space.news
Subject: Informal Electronic Newsletter For The EUVE Science Payload V1.9
Date: 6 Mar 92 04:54:01 GMT
Sender: usenet
Organization: Space Science Labs/Center for EUV Astrophysics
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INFORMAL ELECTRONIC NEWSLETTER FOR THE EUVE SCIENCE PAYLOAD
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Volume 1, Number 9 March 4, 1992
----------------------------------------------------------------
EUVE Launch Date
----------------
May 28, 1992
EUVE Guest Observer NRA
-----------------------
To be released in April 1, 1992. Proposals will be due July 1, 1992.
KSC Update
----------
EUVE is now at Kennedy Space Flight Center, where pre-flight
testing continues in preparation for launch. The first pre-launch
simulation was held March 3. The problem with the tape recorders
has been tracked down and fixed. The tape recorders will be re-
installed in March.
Job Openings at the Center for EUV Astrophysics
-----------------------------------------------
The following positions are available at the Center for EUV As-
trophysics and the Space Sciences Laboratory at the University of
California, Berkeley.
Assistant Research Astronomer/Physicist
Duty Scientist
Post Doctoral Researcher, EGO Center
Science Software Manager
Science Operations Programmer
Scientific Programmer
Staff Research Associate, EGO Center
For further information, contact:
Ms. Cathie Jones
Space Sciences Laboratory
University of California
Berkeley, CA 94720
(510) 642-0816
cjones@ssl.berkeley.edu
The University of California is an Equal Opportunity Affirmative
Action Employer.
----------------------------------------------------------------
The EUVE Electronic Newsletter is issued on a monthly basis, or
as news events arise, by the Center for Extreme Ultraviolet As-
trophysics at the Space Sciences Laboratory, University of Cali-
fornia, Berkeley. The opinions expressed are those of the authors.
Publisher: Roger F. Malina, Managing Editor: Camille Trentacoste
----------------------------------------------------------------
Address all newsletter correspondence to:
pub@ssl.berkeley.edu (Internet)
----------------------------------------------------------------
This newsletter is funded by NASA Contract NAS5-30180.
The EUVE Project is managed by NASA's Goddard Space Flight Center
in Greenbelt, MD. The EUVE Project Manager at GSFC is Mr. Frank
Volpe, the GSFC Project Scientist for EUVE is Dr. Yoji Kondo. The
NASA Headquarters EUVE Program Scientist is Dr. Robert Stachnik,
the NASA Headquarters EUVE Program Manager is Mr. John Lintott.
Further information about the EUVE Guest Observer Program can be
obtained from:
Dr. Yoji Kondo
Mail Code 684
Goddard Space Flight Center
Greenbelt, MD 20771
----------------------------------------------------------------
Will Marchant Center for Extreme Ultraviolet Astrophysics
marchant@ssl.berkeley.edu University of California
KC6ROL@WA6HAM.#NOCAL.CA.USA.NA 2150 Kittredge St., Berkeley, CA 94720 USA
|
| 770.3 | Newsletter - April 6 | VERGA::KLAES | All the Universe, or nothing! | Wed Apr 08 1992 22:24 | 103 |
| Article: 716
From: marchant@ssl.berkeley.edu (Will Marchant)
Newsgroups: sci.space.news
Subject: INFORMAL ELECTRONIC NEWSLETTER FOR THE EUVE SCIENCE PAYLOAD V1 N10
April 6, 1992
Date: 8 Apr 92 19:33:27 GMT
Sender: digester@news.arc.nasa.gov
Organization: Center for EUV Astrophysics
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INFORMAL ELECTRONIC NEWSLETTER FOR THE EUVE SCIENCE PAYLOAD
------------------------------------------------------------------
Volume 1, Number 10 April 6, 1992
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EUVE Launch Date
----------------
The EUVE launch date is May 28, 1992, with an earliest availabil-
ity for launch of May 14. NASA has just set the dates for the
three launch readiness reviews: April 16 (NASA HQ), May 21 (GSFC
at KSC), and May 21 (Air Force at KSC). No new problems with the
spacecraft have been identified which would threaten this launch
date.
NRA Issued for Guest Observers
------------------------------
NASA has issued the first official NASA Research Announcement
for the EUVE Guest Observer Program. The announcement will be
mailed to more than 7000 potential observers, including all
members of the American Astronomical Society. The mailing will
continue through the month of April. If you have not received a
copy by the end of the month, one can be requested from:
Dr. Yoji Kondo
Code 684
NASA Goddard Space Flight Ctr
Greenbelt, MD 20771 USA
(301) 286-6247
Job Openings at the Center for EUV Astrophysics
-----------------------------------------------
The following positions are available at the Center for EUV As-
trophysics and the Space Sciences Laboratory at the University of
California, Berkeley.
Staff Research Associate, EGO Center
Scientific Programmer
For further information, contact:
Ms. Cathie Jones
Center for EUV Astrophysics
2150 Kittredge Street
Berkeley, CA 94720
(510) 642-1263
cjones@ssl.berkeley.edu
UCB is an Equal Opportunity/Affirmative Action Employer.
------------------------------------------------------------------
The EUVE Electronic Newsletter is issued monthly, or as news
events arise, by the Center for Extreme Ultraviolet Astrophysics,
University of California, Berkeley. The opinions expressed are
those of the authors.
Publisher: Roger F. Malina, Managing Editor: Camille Trentacoste
Funded by NASA Contracts NAS5-30180 and NAS5-29298.
------------------------------------------------------------------
Send newsletter correspondence to: pub@ssl.berkeley.edu (Internet)
------------------------------------------------------------------
The EUVE Project is managed by NASA's Goddard Space Flight Center
in Greenbelt, MD. The EUVE Project Manager at GSFC is Mr. Frank
Volpe, the GSFC Project Scientist for EUVE is Dr. Yoji Kondo. The
NASA Headquarters EUVE Program Scientist is Dr. Robert Stachnik,
the NASA Headquarters EUVE Program Manager is Mr. John Lintott.
Information on the EUVE Guest Observer Program is available from:
Dr. Yoji Kondo
Mail Code 684
Goddard Space Flight Center
Greenbelt, MD 20771
(301) 286-6247
kondo@stars.SPAN.NASA.GOV
----------------------------------------------------------------
Will Marchant Center for Extreme Ultraviolet Astrophysics
marchant@ssl.berkeley.edu University of California
KC6ROL@WA6HAM.#NOCAL.CA.USA.NA 2150 Kittredge St., Berkeley, CA 94720 USA
|
| 770.4 | Update - April 8 | VERGA::KLAES | All the Universe, or nothing! | Fri Apr 10 1992 19:53 | 127 |
| Article: 717
From: yee@trident.arc.nasa.gov (Peter E. Yee)
Newsgroups: sci.space.news
Subject: Payload Status for 04/08/92 (Forwarded)
Date: 8 Apr 92 19:41:58 GMT
Sender: usenet@news.arc.nasa.gov
Organization: NASA Ames Research Center, Moffett Field, CA
Delta/EUVE Test & Activity Sheet
April 8, 1992
George Diller
Kennedy Space Center
407/867-2468
Spacecraft: Extreme Ultraviolet Explorer
Project Office: Goddard Space Flight Center
Current Location: Hangar AE, Cape Canaveral
Launch Vehicle: Delta 1
Launch Agency: U.S Air Force
Launch Pad: 17-A
Date: May 28, 1992
Launch Window: 12:22-1:43 p.m. EDT
* Denotes change since last status
UPCOMING TESTS AND ACTIVITIES:
Spacecraft Performance Test (Side B) 4/8-4/11
Install Solar Panels: 4/14-4/15
Install Retroreflectors: 4/17
Begin "Countdown plus early orbit" Mission Simulation #2: 4/20
Install TDRS High Gain Communications Antenna: 4/23
Prepare spacecraft for move to launch pad: 5/12-5/14
Erect Delta First Stage: 4/20 *
Erect Delta solid rocket Castor IV boosters: 4/21-4/23 *
Erect Delta Second Stage: 4/24 *
Erect Payload Adapter Fitting/Perform Interface Test: 4/24 *
Hoist fairing to white room: 4/27 *
First Stage LOX Leak Checks: 5/13
Delta Simulated Flight: 5/14
Delta Flight Program Verification: 5/20
Ordnance Installation: 5/21
Move spacecraft to pad: 5/14 *
Spacecraft Launch Pad Functional Testing: 5/16-5/18
Fairing Installation: 5/22-5/23
Delta Second Stage Servicing: 5/26
Retract mobile service tower for launch: 5/28 0700
ACTIVITIES COMPLETED:
Science Payload Module arrival: 1/27
Explorer Platform arrival: 1/28
Intallation of pyrotechnics completed: 1/30
Contamination witness mirror changeout: 1/31
Initial spacecraft performance checks complete: 2/22
Mated Explorer Platform to science Payload Module: 2/24
Optical alignment completed: 2/26
Install Witness Mirror: 3/2
"Countdown plus early orbit" mission simulation completed: 3/6
Flight Batteries Installed in Power Module: 3/9
Installed Power Module: 3/11
Payload Module Blanket Installation completed: 3/11
Removal of Control and Data Handler (C&DH): 3/11
Installation of Flight Data Recorder into C&DH: 3/11
TDRS Orbit Navigation System (TONS) retesting complete: 3/21
Reinstall Control and Data Handler (C&DH): 3/22
Clean Spacecraft: 3/22
Omni Antenna RF Testing: 3/23
Hardware/Software Interface Testing complete: 3/20
Spacecraft Performance Test (Side A) complete: 3/27
RF Omni Antenna Test complete: 3/28
Hardware/Software Interface Testing complete: 4/3
PAYLOAD TEST AND ACTIVITY SHEET
Tethered Satellite/EURECA
April 8, 1992
George Diller
NASA Kennedy Space Center
407/867-2468
FTS 823-2468
Mission: STS-46
Orbiter: OV-104 Atlantis
Crew: 7
Pad: 39-B
Launch timeframe: July wk 2
Launch window: mid-morning
Mission Duration: 7 days
Landing Site: KSC (early morning)
Primary TAL: Ben Guerir
Orbit: 185 statute miles 28.5 degrees
Current location: Operations & Checkout Building (O&C)
Upcoming Activity: (* denotes change since last status)
O&C CITE testing 4/8-15
EURECA arrives VPF 5/15 *
Install TSS into payload canister 6/5
Transfer TSS to Pad B 6/12
Install TSS into Atlantis payload bay 6/16
Activity Completed:
TSS arrival 11/16/90
Reel Assembly mated to experiment pallet 2/8/91
Final fit check with Satellite Support Assembly (SSA) 4/12
Satellite Support Assembly mated to experiment pallet 7/16
Flight tether installed 9/11
Flight tether testing completed 9/13
Deployer to pallet IVT completed 10/21
Mate Satellite to Satellite Support Assembly 12/18
Connect tether to satellite/mate to deployer boom 1/15/92
Satellite System and Experiment Functional Tests complete 2/28
Satellite IVT Complete 2/29
Begin Satellite closeout activities 3/17
Power on TSS/load software for MST 3/17
Mission Sequence Test 3/19-3/24
Move to CITE stand 4/2
|
| 770.5 | EUVE Press Kit Available | PRAGMA::GRIFFIN | Dave Griffin | Tue May 12 1992 16:26 | 6 |
| pragma::public:[nasa]euve.ps
6 pages.
- dave
|
| 770.6 | EUVE moves to Complex 17 | PRAGMA::GRIFFIN | Dave Griffin | Thu May 21 1992 22:20 | 42 |
| George H. Diller May 21, 1992
Kennedy Space Center
Dolores Beasley
Goddard Space Flight Center
RELEASE: 56-92
NASA's Extreme Ultraviolet Explorer spacecraft will be moved
this evening from the cleanroom facility at Hangar AE to Launch
Complex 17 on Cape Canaveral Air Force Station, Fla. The move of
EUVE, contained in an environmentally controlled canister, is
scheduled to begin at 8 p.m. EDT with arrival at Pad 17-A about
an hour later. Hoisting of EUVE into the gantry for soft mating
atop the Air Force Delta 2 rocket is scheduled for about 10 p.m.
EDT. The mechanical hard mate between EUVE and the Delta second
stage is scheduled for Friday, May 22.
EUVE will then begin approximately 10 days of integrated
spacecraft and vehicle testing. Final spacecraft processing was
completed the first week of this month. Earlier this week, the
spacecraft was integrated with the Delta rocket's payload adapter
fitting. EUVE was then prepared for the trip to the launch pad.
Tonight's move culminates the prelaunch processing which began
with the spacecraft's arrival from Goddard Space Flight Center,
Greenbelt, Md. at the end of January.
The Air Force Delta II rocket was erected on Pad A at
Complex 17 during the week of April 20 and prelaunch testing and
flight preparation of the vehicle has been going smoothly.
Encapsulation of the spacecraft in the nose fairing is scheduled
to occur on May 29.
EUVE is a satellite designed to observe astronomical objects
at extreme ultraviolet wavelengths, one of the least-studied
portions of the electromagnetic spectrum. The Goddard Space
Flight Center manages the project for NASA's Office of Space
Science and Applications, Astrophysics Division, Washington, D.C.
The launch is targeted to occur on Thursday, June 4, during
a launch window which extends from 12:23 to 1:43 p.m. EDT.
|
| 770.7 | EUVE launched into Earth orbit | VERGA::KLAES | All the Universe, or nothing! | Mon Jun 08 1992 20:29 | 109 |
| Article: 2434
From: clarinews@clarinet.com (WILLIAM HARWOOD, UPI Science Writer)
Newsgroups: clari.tw.space
Subject: Astronomy satellite launched
Date: Sun, 7 Jun 92 12:01:22 PDT
CAPE CANAVERAL, Fla. (UPI) - An unmanned Delta 2 rocket
boosted a $214 million NASA astronomy satellite into orbit Sunday to
study high-energy ultraviolet radiation from deep space, research
expected to shed light on how the Sun works.
Roaring with power, the 123-foot Delta 2 thundered to life at
12:40 p.m. EDT and quickly streaked away from the Cape Canaveral Air
Force Station, three days late because of ground processing problems
last week and stormy weather Saturday.
Liftoff Sunday was 13 minutes behind schedule to give the
Russian space station Mir time to pass safely overhead and to allow an
aircraft to get out of the launch danger zone.
But once off the pad, it was clear sailing as the slender
rocket, bought from the Air Force for $46 million, put on a
spectacular afternoon skyshow for thousands of local residents and
tourists enjoying a sunny day at area beaches.
The Air Force-conducted launch was flawless and 71 minutes
after liftoff, NASA's Extreme Ultraviolet Explorer, a solar-powered
$214 million satellite equipped with four compact telescopes, was
safely ejected into a 340-mile-high orbit.
The ``EUVE'' -- pronounced U'-vee -- is one in a series of
``Explorer'' satellites designed to explore different aspects of the
Universe.
The most recent previous such mission was that of the Cosmic
Background Explorer, a spectacularly successful effort that is helping
astronomers rewrite the history of the early Universe and the Big Bang
explosion thought to have created it 10 billion to 20 billion years ago.
Earlier explorer missions studied infrared emissions from
deep space and took a preliminary look at astronomical sources of
ultraviolet radiation, which cannot penetrate Earth's atmosphere.
The goal of the EUVE mission is to conduct the most detailed
ultraviolet observations to date. By doing so, scientists hope to
learn more about the chemical and physical processes at work in
different types of stars.
For the first six months of the mission, two sky surveys will
be conducted. In one, EUVE's three scanning telescopes will map the
positions of bright ultraviolet sources across the sky. At the same
time, a ``deep survey telescope'' will look for fainter, more
difficult-to-detect sources of UV radiation.
Once the sky surveys are complete, a sensitive spectrometer
will be used to study the light from individual objects in great detail.
``Why are we studying the extreme ultraviolet? It's because
it's the last wavelength region we haven't studied,'' said NASA
astronomer Edward Weiler.
``If it's important to study the objects in the Universe then
it's important to study them in as many wavelengths as possible. If
you don't do that, you're missing a whole part of the Universe.''
The importance of studying the entire electromagnetic spectrum
is analagous to listening to a symphony. Unless the listener can hear
all of the instruments, the composer's intent cannot be fully
appreciated. Likewise, astronomers need to see how the Universe
appears across the electromagnetic spectrum to fully understand the
forces at work in the Cosmos.
In order of increasing energy, the electromagnetic spectrum
runs in a smooth continuum from radio waves to infrared, visible
light, ultraviolet radiation, X-rays and gamma rays.
The type of radiation produced by a star or other astronomical
body provides a sort of spectral fingerprint that allows scientists to
study the physical, chemical and nuclear processes at work in such
objects. The higher the energy, the hotter the object and UV radiation
covers a range of temperature from 50,000 to 1 million degrees.
The Hubble Space Telescope is studying visible light while
the Compton Gamma Ray Observatory is at work mapping sources of
high-energy nuclear radiation. A Hubble-class X-ray telescope mission
is scheduled for launch later this decade and NASA eventually hopes to
build a similar infrared facility.
While it is not in the ``great observatory'' class like Hubble
and Compton, EUVE nonetheless represents the most ambitious attempt
yet to study ultraviolet emissions from deep space.
If all goes well, EUVE will probe the chemical composition of
the nearby interstellar medium, the collapsed remnants of normal stars
-- white dwarfs -- hot, young stars and the atmospheres of cooler
stars. By studying such stellar atmospheres, scientists hope to learn
more about Earth's Sun.
``This is another brick in the house of trying to understand
how solar atmospheres work,'' Weiler said. ``The Sun affects every
person on Earth. When there's a huge solar flare, which is usually
totally unpredictable, it disrupts communications and so on.
``EUVE by itself is not going to...tell us exactly how the Sun
works and how to predict it. It will not do that. (But) in combination
with X-ray satellites, the Hubble, ground-based telescopes over the
course of years...I think we'll have a much better understanding of
our Sun...than we have right now.''
|
| 770.8 | EUVE Newsletter announcement | VERGA::KLAES | All the Universe, or nothing! | Mon Jun 15 1992 15:48 | 68 |
| Article: 1162
From: camille@ssl.Berkeley.EDU (Camille Trentacoste)
Newsgroups: sci.space.news
Subject: EUVE Launch Successful
Date: 9 Jun 92 23:54:33 GMT
Sender: usenet@news.arc.nasa.gov
Organization: Space Sciences Laboratory, University of California at Berkeley
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INFORMAL ELECTRONIC NEWSLETTER FOR THE EUVE SCIENCE PAYLOAD
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Volume 1, Number 14 June 9, 1992
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EUVE LAUNCHES SUCCESSFULLY
The Extreme Ultraviolet Explorer satellite was successfully
launched from Launch Complex 17A at Cape Canaveral Air Force Sta-
tion, Florida, at 12:40 pm EDT (16:40 GMT) on Sunday, June 7,
1992. All systems were green and go at the start of the launch
window at 12:24 EDT, but there was a slight hold due to an air-
craft in the launch range. The spacecraft orbit has been
described as "perfect," with variation from the nominal altitude
of approximately 2/10 of a nautical mile.
The MAPS high-gain antenna was deployed, and the EUVE Science
Operations Center at UC Berkeley is receiving good telemetry via
TDRSS.
The spacecraft has spent time in inertial mode with stars in both
star trackers. It has also spent some time spinning at 1.3 RPO
for star acquisition purposes.
The Flight Operations Team has successfully converged aspect, and
experiments with controlled slewing are underway.
Guest Observer Proposals are still due on July 1, 1992.
------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for
Extreme Ultraviolet Astrophysics, University of California,
Berkeley. The opinions expressed are those of the authors.
Publisher: Roger F. Malina, Managing Editor: Camille Trentacoste
Funded by NASA Contracts NAS5-30180 and NAS5-29298.
------------------------------------------------------------------
Send newsletter correspondence to: pub@ssl.berkeley.edu (Internet)
------------------------------------------------------------------
The EUVE Project is managed by NASA's Goddard Space Flight Center
in Greenbelt, MD. The EUVE Project Manager at GSFC is Mr. Frank
Volpe, the GSFC Project Scientist for EUVE is Dr. Yoji Kondo, the
Deputy Project Scientist is Dr. Ronald Oliversen. The NASA Head-
quarters EUVE Program Scientist is Dr. Robert Stachnik, the Depu-
ty Program Scientist is Dr. Derek Buzasi, the NASA Headquarters
EUVE Program Manager is Mr. John Lintott. Information on the
EUVE Guest Observer Program is available from:
Dr. Yoji Kondo, Mail Code 684 GSFC, Greenbelt, MD 20771
(301) 286-6247 - kondo@stars.SPAN.NASA.GOV
----------------------------------------------------------------
|
| 770.9 | EUVE's first targets | VERGA::KLAES | Slaves to the Metal Hordes | Wed Jun 24 1992 21:22 | 110 |
| Article: 1251
Newsgroups: sci.space.news
From: Roger "F." Malina <rmalina@cea.Berkeley.EDU>
Subject: EUVE sees first light
Sender: usenet@news.arc.nasa.gov
Organization: EUVE Folks, University of California at Berkeley
Date: Mon, 22 Jun 1992 16:20:24 GMT
EUVE OBSERVATORY SEES FIRST LIGHT
The seven detectors of the EUVE Observatory were turned on succesfully
one hour ago and obtained their first images of the EUV sky. All
detectors are operating well, with the background in all detectors
counting at low count rates. The geocoronal 304 A and interplanetary
584 A glow were detected at nominal count rates in the spectrometer.
The first in orbit calibrations will begin tomorrow.
The deadline for Guest Observer proposals is July 1 - get your
proposals in!! EUVE is operational.
Roger Malina
Article: 1262
From: camille@cea.Berkeley.EDU (Camille Trentacoste)
Newsgroups: sci.space.news
Subject: EUVE Observes First Targets
Date: 23 Jun 92 22:47:07 GMT
Sender: usenet@news.arc.nasa.gov
Organization: Center for EUV Astrophysics, University of California at Berkeley
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INFORMAL ELECTRONIC NEWSLETTER FOR THE EUVE SCIENCE PAYLOAD
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Volume 1, Number 14 June 23, 1992
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EUVE OBSERVES FIRST CALIBRATION TARGETS
The EUVE Observatory has started to observe its first calibration
targets. Last night the hot white dwarf 1254 +223 was observed
and was detected strongly in the scanner A, B and C detectors.
The source was detected in the longest wavelength survey detector
(Tin).
The hot white dwarf 1620 -391 was used to calibrate the deep sur-
vey and spectrometer detectors.
EUVE OBSERVATORY SEES FIRST LIGHT
The seven detectors of the EUVE Observatory were turned on suc-
cessfully on Sunday, June 21, and obtained their first images of
the EUV sky. All detectors are operating well, with the back-
ground in all detectors counting at low count rates. The geo-
coronal 304 A and interplanetary 584 A glow were detected at nom-
inal count rates in the spectrometer. The first in-orbit calibra-
tions began on Monday, June 22.
The deadline for Guest Observer proposals is July 1 - get your
proposals in!! EUVE is operational.
EUVE CALIBRATION TARGETS MODIFIED DUE TO LAUNCH SLIPS
The EUVE Instrument Scientist Pat Jelinsky reports that due to
the EUVE launch slip, there were small adjustments to the cali-
bration targets for EUVE.
Here are the spectrometer targets that cannot be observed because
of the launch slip:
GJ 644A
Sco X-1
Here are the spectrometer targets that were added because of the
launch slip:
AT Mic
PKS 2155-304
All of these targets are listed in the "EUVE Deep
Survey/Spectrometer Calibration Target List (April 16, 1992)."
------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for
Extreme Ultraviolet Astrophysics, University of California,
Berkeley. The opinions expressed are those of the authors.
Publisher: Roger F. Malina, Managing Editor: Camille Trentacoste
Funded by NASA Contracts NAS5-30180 and NAS5-29298.
------------------------------------------------------------------
Send newsletter correspondence to: pub@ssl.berkeley.edu (Internet)
------------------------------------------------------------------
The EUVE Project is managed by NASA's Goddard Space Flight Center
in Greenbelt, MD. The EUVE Project Manager at GSFC is Mr. Frank
Volpe, the GSFC Project Scientist for EUVE is Dr. Yoji Kondo, the
Deputy Project Scientist is Dr. Ronald Oliversen. The NASA Head-
quarters EUVE Program Scientist is Dr. Robert Stachnik, the Depu-
ty Program Scientist is Dr. Derek Buzasi, the NASA Headquarters
EUVE Program Manager is Mr. John Lintott. Information on the
EUVE Guest Observer Program is available from:
Dr. Yoji Kondo, Mail Code 684 GSFC, Greenbelt, MD 20771
(301) 286-6247 - kondo@stars.SPAN.NASA.GOV
----------------------------------------------------------------
|
| 770.10 | Update - July 1 | VERGA::KLAES | Slaves to the Metal Hordes | Fri Jul 10 1992 19:47 | 161 |
| Article: 1368
Newsgroups: sci.space.news
From: EUVE Instrument "P.I." <rfm@cea.Berkeley.EDU>
Subject: EUVE WORKS GREAT !
Sender: usenet@news.arc.nasa.gov
Organization: Center for EUV Astrophysics, University of California at Berkeley
Date: Fri, 3 Jul 1992 04:20:48 GMT
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INFORMAL ELECTRONIC NEWSLETTER FOR THE EUVE SCIENCE PAYLOAD
------------------------------------------------------------------
Volume II, Number 1 July 1, 1992
------------------------------------------------------------------
EUVE OBSERVATORY IS OPERATIONAL _ WORKS GREAT
by Roger F. Malina
Every morning I walk into work and ask "What did we discover last night?"
The EUVE instruments have now completed their initial in orbit
checkout and I am pleased to say that all instruments are working
with no significant problems. The data analysis pipelines are
working smoothly ( processing time is 45% of real time, compared
to our pre-launch goal of 30% of real time).
I can report that we have "several" possible new EUV sources that
EUVE has discovered. We are currently analyzing these in detail
to make sure they are real. Ironically, we had not planned to
start analyzing data for new sources until the start of the sky
survey beginning July 22, but we may be able to announce new EUV
sources before the actual start of the mission !!!! As a word of
caution, the first new EUV source we thought we had discovered
proved to be an artifact because of the numerous pointing
maneuvers during the checkout period that led to some confusion
initially in the data reduction. We will make sure that
we do not release new source announcements until we have scrubbed
the data back very hard. Watch this space.
We now have several calibration spectra in hand. Analysis of
these spectra is going on for performance verification (we have
had to make sure that data that may belong to GO's is not
released accidentally). Initial performance analysis indicates
that the instrument throughputs and backgrounds are close to
those described in the EUVE Observers Handbook. The spectra are
BEAUTIFUL. The instrument alignements have now been measured
from the in orbit data and we are setting the alignment offsets.
Initial performance analysis has also been carried out of the
EUVE background, comparing these to models of the geocoronal and
geophysical background. The models match the data well and indi-
cate that the solar EUV is somewhat fainter than we had assumed
in our conservative assumptions. The initial analysis of the
charged particle background indicates that our magnetic brooms
and repeller grids are working well to exclude the charged parti-
cles. We are seeing very very low countrates down the earth's
shadowcone indicating that the EUVE deep survey is likely to be
very very sensitive. I overhead someone say the other day "Is
this real data or is it simulated ?". It is very hard to tell the
difference !
On the engineering front we are working on a number of small is-
sues on the performance of the instruments. These have all been
reported in the daily reports and pose no threat to science or
health and safety. We continue, for instance, to see occasional
short-lived bursts (under a few seconds) where a single detector
count rises to above a 1000 c/s (from the usual 10- 100 c/s).
These may be related to the major solar storm alerts that have
occurred over the past ten days. We also see occasional events
due to high energy charged particles. These overload our
amplifiers and are mis-imaged. We are currently adjusting the
detector thresholds to eliminate these events. In the early days
of the instrument checkout, one of the detectors (Scanner A)
went into a soft scrub mode - this resulted in an enhanced background
for a few days but the detector is back to normal count rates
and operating fine.
We have no new pinholes that developed during launch or the two and
half year integration period since we delivered the instruments
to NASA. We do see the two pin holes that we had seen and calibrated
during ground test. The image from the pin hole mimicks the ray tracing
model runs that we had carried out. The detector backgrounds are
very smooth with no significant detector hotspots other than the
few very faint ones that we already knew about.
Last week we safed our instruments in anticipation of the
solar eclipse. We were concerned that our software might
get confused by the additional "day/night" commands that
we would receive as we went in and out of the eclipse. As
it turned out, before we went into the eclipse we received
a "safing" command from the spacecraft because a planned
slew had overshot a safety limit. It took us 13 hours to
get all the instruments reset and operational again- I
am sorry to report that the GSFC Flight Operations Team
were able to get the spacecraft itself operational again
in a few hours and beat us to the punch. We will do
better next time ! Or better - the next time may never occur.
The EUVE spacecraft has been operating very smoothly from
the science instruments point of view. We have been watching
the anomaly resolution on one star tracker and overheating of
the gimbal motors on the antenna. These anomalies now seem to be controlled
and the spacecraft operations is going very smoothly. The
GSFC Flight Operations Team is doing great- maybe its true
that data solves all problems. Certainly the pre-launch
friction on mission operations has evaporated as the data
has started pouring in.
The EUVE instruments are working according to plan. We are on
schedule for the In-Orbit Calibration and will
start the sky survey as scheduled on July 22/23.
The excitement around here is palpable. We have a first rate ob-
servatory in EUVE and we look forward to reporting our first sci-
ence results. We hope you all got your GO proposals submitted by
the deadline of July 1 - the EUVE Guest Observer Support Group
has done their first release of the GO software under IRAF and
is ready to start distributing data as soon as the GO program
starts in January. The GO software package has been used to
reduce the in-orbit calibration data and is running very well.
I remember the excitement here in 1975 during the Apollo-Soyuz
mission when the first non-solar EUV source was discovered.
Stu Bowyer, Mike Lampton, Bruce Margon, Francesco Paresce,
and Bob Stern reported that the star HZ43 "blew them off the
console". That was July, 17 years ago. On the sand at Cocoa
Beach they dreamed of building a satellite dedicated to
EUV astronomy. The last window on the Universe.... EUVE is
now in orbit. Its even visible in binoculars in the evening sky.
Only Stu Bowyer and Mike Lampton from the original team are still
here at Berkeley to enjoy the thrill of discovery in real time,
and numerous scientists who have "done time" on EUVE are spread around
the country and abroad. Your observatory is now in orbit ! Thanks for your
help- we look forward to welcoming you back to Berkeley to enjoy
the discoveries.
------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for
Extreme Ultraviolet Astrophysics, University of California,
Berkeley. The opinions expressed are those of the authors.
Publisher: Roger F. Malina, Managing Editor: Camille Trentacoste
Funded by NASA Contracts NAS5-30180 and NAS5-29298.
Send newsletter correspondence to: pub@ssl.berkeley.edu (Internet)
------------------------------------------------------------------
The EUVE Project is managed by NASA's Goddard Space Flight Center
in Greenbelt, MD. The EUVE Project Manager at GSFC is Mr. Frank
Volpe, the GSFC Project Scientist for EUVE is Dr. Yoji Kondo, the
Deputy Project Scientist is Dr. Ronald Oliversen. The NASA Head-
quarters EUVE Program Scientist is Dr. Robert Stachnik, the Depu-
ty Program Scientist is Dr. Derek Buzasi, the NASA Headquarters
EUVE Program Manager is Mr. John Lintott. Information on the
EUVE Guest Observer Program is available from: Dr. Yoji Kondo,
Mail Code 684 GSFC, Greenbelt, MD 20771 (301) 286-6247 -
euve@stars.SPAN.NASA.GOV
----------------------------------------------------------------
|
| 770.11 | Update - July 13 | VERGA::KLAES | Slaves to the Metal Hordes | Tue Jul 14 1992 19:51 | 157 |
| From: DECWRL::"usenet-space-news-request@ames.arc.nasa.gov" 13-JUL-1992
22:29:19.99
To: sci-space-news@ames.arc.nasa.gov
CC:
Subj: EUVE Update
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INFORMAL ELECTRONIC NEWSLETTER FOR THE EUVE SCIENCE PAYLOAD
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Volume 2, Number 2 July 13, 1992
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NEWS SUMMARY:
+ EUVE calibration phase continues--15 EUV sources observed so far
+ Two potential new EUV sources under study
+ Two EUVE sources show evidence for variability
+ UV leak calibration carried out--no problems found
+ Initial daytime data test carried out
+ Geomagnetic storm caused enhanced background in some detectors
+ Occasional large bust events being analyzed--probably not cosmic
+ AAVSO program begins: interested observers urged to contact EUVE
+ EUVE Public Archive opens for business
+ Sky Survey phase to start on schedule July 23
CALIBRATION AND CHECK-OUT PROGRAM:
Instrument Stellar Calibration
--------------------------------
The EUVE in-orbit calibration phase continued without a hitch
this week. The EUV stars that have now been observed and detected
include: WD 1254 +223, WD 1620 -391, AR Lac, WD 1845 +019, WD
0050 -332, WD 2111 +498, AT Mic, MCT 2020 -4234, Her X-1, RE 1938
-461. These have been used to calibrate the boresights of all
the instruments and also to carry out an initial calibration of
the spectrometer channels. The final calibrations will conclude
this week. The sky survey phase will start on schedule July 23.
Her X-1 was observed to attempt a GMT-versus-spacecraft time
calibration. Initial indications are that the data will allow
this to be done successfully.
Initial analysis indicates that some of the calibration targets
have been observed in the EUVE Long Wavelength Filter (tin).
These targets will be good candidates for the long term calibra-
tion monitoring program. We plan to re-observe a small sample of
sources detected at all EUV wavelengths on a monthly basis to
search for any evidence of instrument degradation.
UV Leak Calibration
--------------------
Initial analysis of the bright B stars observed does not indicate
any significant UV leaks in the EUVE filters.
Initial Daytime Operations Test
--------------------------------
An initial test of operation in the daytime was carried out with
the short wavelength scanners. The count rates observed in the
aluminum filter were low and indicate that daytime data will be
feasible. Count rates in the lexan filter rose significantly dur-
ing the scan, which crossed the sunlit earth. Detected counts
are attributed to the residual UV transmission longward of 2000
angstroms at a level of 10(-10). Variability in the observed flux
is either due to variations in reflected UV from cloud cover, or
to ozone band emission variations. Further daytime tests are
planned once EUVE begins sky survey mode July 23, including tests
of the spectrometer channels.
Geomagnetic storm
-----------------
During last week a geomagnetic storm storm was detected in some
of the filters. Count rates rose as high as 600 c/s. The data is
being analyzed to understand the source of the emissions.
South Atlantic Anomaly
---------------------
The boundaries of the South Atlantic Anomaly are being mapped to
determine the relevant charged particle contours for data quality
flags.
Large Bursts
------------
About 16 large count-rate bursts have been detected in the EUVE
detectors. Count rates go as high as 8000 c/s for time scales
less than a few seconds. The source of these bursts is not under-
stood. The co-aligned telescopes do not see bursts simultaneous-
ly; however, the pulse height of the burst counts is not as high
as would be expected for large charged particle events.
SCIENCE PROGRAM:
Potential Sources Scrutinized
-----------------------------
At the marathon EUVE science team meeting last Friday, two poten-
tial new EUV sources were presented. Potential optical counter-
parts of these new EUVE sources include a white dwarf and a cool
star. These two sources are the ones that have survived scrutiny
by the Data Analysis Team so far. A number of other potential new
sources did not survive detailed scrutiny, others potential new
sources are still being checked carefully. The two new EUVE
sources have now been assigned to EUVE scientists for further
checking, optical counterpart verification and publication.
All 15 sources detected so far are being checked for any evidence
of variability. At the science team meeting Friday, scientists
presented evidence of variability for two of the sources in the
EUVE catalogue. These sources have also been assigned to scien-
tists for further checking and scientific publication.
AAVSO and Optical Monitoring Program
-------------------------------------
The AAVSO is initiating a program to provide contemporaneous ob-
servations of variable stars during the periods when they will be
observed by EUVE during the sky survey. Any observers interested
in being involved in this program should contact Dr. Robert
Patterer at rjp@cea.berkeley.edu. Observers will receive informa-
tion on the planned dates for which individual stars will be
visible to EUVE.
EUVE Public Archive
-------------------
The EUVE Public Data Archive is opening for business next week.
The first data that will be made publicly available includes the
first-light images. Each issue of this electronic newsletter will
contain announcements of data that is being released publicly.
If you wish to obtain publicly available EUVE data, or a listing
of what is available, please contact Dr. Jeremy Drake at
archive@cea.berkeley.edu
------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for
Extreme Ultraviolet Astrophysics, University of California,
Berkeley. The opinions expressed are those of the authors.
Publishers: Roger F. Malina, C. Stuart Bowyer
Managing Editor: Camille Trentacoste
Funded by NASA Contracts NAS5-30180 and NAS5-29298
------------------------------------------------------------------
Send newsletter correspondence to: pub@cea.berkeley.edu (Internet)
------------------------------------------------------------------
The EUVE Project is managed by NASA's Goddard Space Flight Center
in Greenbelt, MD. The EUVE Project Manager at GSFC is Mr. Frank
Volpe, the GSFC Project Scientist for EUVE is Dr. Yoji Kondo, the
Deputy Project Scientist is Dr. Ronald Oliversen. The NASA Head-
quarters EUVE Program Scientist is Dr. Robert Stachnik, the Depu-
ty Program Scientist is Dr. Derek Buzasi, the NASA Headquarters
EUVE Program Manager is Mr. John Lintott. Information on the
EUVE Guest Observer Program is available from:
Dr. Yoji Kondo, Mail Code 684 GSFC, Greenbelt, MD 20771
(301) 286-6247 - euve@stars.SPAN.NASA.GOV
----------------------------------------------------------------
|
| 770.12 | Update - July 19 | VERGA::KLAES | Slaves to the Metal Hordes | Fri Jul 24 1992 22:11 | 126 |
| Article: 1493
Newsgroups: sci.space.news
From: rmalina@cea.berkeley.edu
Subject: EUVE newsletter for 07/19/92 [Volume 2, Number 3]
Sender: usenet@news.arc.nasa.gov
Organization: Center for EUV Astrophysics, University of California at Berkeley
Date: Mon, 20 Jul 1992 17:44:34 GMT
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INFORMAL ELECTRONIC NEWSLETTER FOR THE EUVE SCIENCE PAYLOAD
------------------------------------------------------------------
Volume 2, Number 3 July 19, 1992
------------------------------------------------------------------
EUVE OBSERVATORY CONTINUES TO OPERATE SMOOTHLY
----------------------------------------------
The EUVE Observatory continues to operate smoothly and carried out
another week of in orbit calibration of the instruments. The
calibration stars this week included RE 0029 -632, WD 0004 +330, AU
MIC, MCT 2020 -4234 and alpha Centauri. Initial reduction of the AU
MIC data show that spectral lines were observed throughout the short
and medium wavelength spectrometers; a single 10 minute segment of
data was sufficient to allow detection of some spectral lines. The AU
MIC data will allow the initial wavelength calibration to be carried out.
In mid week Scanner B detector was turned off due to an anomaly of the
high count rate HV shut down software. This detector failed to turn
off during two day time passes due to problem arising from the
overlapping of the South Atlantic Anomaly and the day/night signals,
together with the actual rise time of the count rates. Scanner B was
the only one of the 7 detectors to exhibit this anomaly. The count
rate throughout the day time however did not exceed 1300 c/s (
indicating that we may in fact be able to operate some detectors in
the daytime). A software patch has been loaded and Scanner B is now
operating again.
The IOC calibration period is due to be completed this week with start
of the science mission with the sky survey July 22/23. Some additional
checkout tests may delay the start of the sky survey by one day.
THE EUVE IOC checkout and calibration period has really been going
remarkably smoothly. All tasks have been carried out on schedule and
all subsystems checked out. This is a wonderful observatory.
CEA Public Data Archive Opens
-----------------------------
The EUVE Public Data Archive is now open for business, and we are
pleased to announce the first public release of spectral data ob-
tained as part of the In Orbit Calibration (IOC). This inaugural
release is a raw spectrum of the white dwarf WD1620-391, as seen
in the short wavelength spectrometer. The data is available
electronically through the new EUVE Data Archive mail server,
from the CEA FTP site, or alternatively, in hardcopy form through
conventional mail or facsimile transmission.
This spectrum of the White Dwarf 1620 -391 is being released in
raw form of observed counts versus detector bins; analysis of the
in orbit calibration data is under way to obtain the bin to wavelength
calibration and the absolute intensity calibration. These calibrations
are not yet available. The raw calibration data will be particularly
valuable to approved GO's to help plan EUVE observing runs, and
to compare with data on GO targets.
To access the ftp site, ftp to superego@cea.berkeley.edu. Change
directory to pub/archive. Files available are listed in the
file index.
To obtain information concerning the Archive mail server, send a
mail message containing the word "help" (omit quotes) on the
first line, with no preceding spaces, to
archive@cea.berkeley.edu; a file containing information on the
mail server will be returned to you automatically. Although the
mail server is designed for processing requests for information
automatically, mail messages which do not address the server pro-
gram are sent to Archive personnel, and are handled on an indivi-
dual basis.
Other queries concerning the EUVE Data Archive should be ad-
dressed to archive@cea.berkeley.edu, or to:
Dr. Jeremy Drake
Center for EUV Astrophysics
University of California
2150 Kittredge Street
Berkeley CA 94720
Tel: (510) 642-3032 FAX: 643-5660
Further releases of EUVE data will be announced in future edi-
tions of the Newsletter.
For information about EUVE data rights policies governing the IOC
calibration data contact Dr Yoji Kondo, EUVE Project Scientist
at the address below.
------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for
Extreme Ultraviolet Astrophysics, University of California,
Berkeley. The opinions expressed are those of the authors.
Publishers: Roger F. Malina, C. Stuart Bowyer
Managing Editor: Camille Trentacoste
Funded by NASA Contracts NAS5-30180 and NAS5-29298
------------------------------------------------------------------
Send newsletter correspondence to: pub@cea.berkeley.edu (Internet)
------------------------------------------------------------------
The EUVE Project is managed by NASA's Goddard Space Flight Center
in Greenbelt, MD. The EUVE Project Manager at GSFC is Mr. Frank
Volpe, the GSFC Project Scientist for EUVE is Dr. Yoji Kondo, the
Deputy Project Scientist is Dr. Ronald Oliversen. The NASA Head-
quarters EUVE Program Scientist is Dr. Robert Stachnik, the Depu-
ty Program Scientist is Dr. Derek Buzasi, the NASA Headquarters
EUVE Program Manager is Mr. John Lintott. Information on the
EUVE Guest Observer Program is available from:
Dr. Yoji Kondo, Mail Code 684 GSFC, Greenbelt, MD 20771
(301) 286-6247 -- euve@stars.SPAN.NASA.GOV
----------------------------------------------------------------
|
| 770.13 | Update - August 10 | VERGA::KLAES | Slaves to the Metal Hordes | Fri Aug 14 1992 21:02 | 114 |
| Article: 1693
Newsgroups: sci.space.news
From: Camille Trentacoste <camille@cea.berkeley.edu>
Subject: EUVE Newsletter
Sender: usenet@news.arc.nasa.gov
Organization: Center for EUV Astrophysics, University of California at Berkeley
Date: Thu, 13 Aug 1992 04:33:48 GMT
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY Vol 2, No.5 8/10/92
------------------------------------------------------------------
EUVE CONTINUES SKY SURVEY
-------------------------
The EUVE observatory is now in the second week of the sky survey.
All instruments and the spacecraft continue to operate nominally.
EUV sources are being detected on a regular basis.
The initial processing of the first week of sky survey data re-
vealed a timing offset between the telemetry and the attitude
solution, resulting in source positions with a systematic offset
of a tenth of a degree. This has now been corrected and the
first week is being reprocessed.
The first new EUV sources have now been detected in the sky sur-
vey data. One of the new deep survey sources is located in the
same field of view as a previously reported ROSAT WFC source. The
new source is of similar intensity as the ROSAT WFC source.
Several of the EUV sources observed so far have proved to be dou-
ble.
Count rates observed by EUVE appear to be significantly higher
than the reported count rates from the ROSAT WFC for many
sources. This is not fully understood at this time.
The moon was imaged in the sky survey detectors, including the
long wavelength scanner. The count rates are considerably lower
than the modeled predictions. As a result the moon will cause
less contamination than feared, and will not result in high count
rate shutoff of the detectors. The moon was also used to map
residual stray light and leaks out of field of view. There were
no surprises.
Calibration data from AU Mic are being analyzed. The source
flared strongly twice during the calibrations. Many spectral
lines were detected in both the short and long wavelength spec-
trometers so that wavelength calibration will be possible using
this data.
AR Lac and II Peg were both well observed during the calibrations
and the data are being analyzed.
At the Friday science team meeting there was much discussion of
the very low backgrounds seen in the detectors and implications
for models of emission from the interstellar medium. Initial
analysis of the scanning spectrometer data by Vallerga and Jelin-
sky are encouraging also and indicate that the spectrum of the
background obtained during the sky survey will be scientifically
very interesting.
EUVE BIBLIOGRAPHY AVAILABLE
---------------------------
The complete bibliography of EUVE papers from the Center for EUV
Astrophysics is now available from the Public Archive via ftp.
The file EUVE_bib is a listing, in troff format, of all the EUVE
papers, categorized by subject.
To request one or more papers, e-mail editorial@cea.berkeley.edu,
giving your postal address and the number(s) of the paper(s) you
want from the list.
Due to a transcription error, the FTP address for the EUVE ar-
chive which appeared in the last Newsletter was incorrect. To
reach the anonymous FTP site, ftp to
cea-ftp.cea.berkeley.edu
At the "Name" prompt, type (excluding the quotes) "anonymous",
and for a password please type in your e-mail address. The pass-
words used are logged, enabling us keep a record of those who
have accessed the facility, and to deal with any queries or prob-
lems more promptly. The FTP site is currently shared by the EUVE
Archive and the EUVE Guest Observer Program: information pertain-
ing to both of these may be retrieved from the same site. If you
are unfamiliar with FTP (File Transfer Protocol), a list of
available commands may be obtained by typing (again, omitting the
quotes) "help" or "?". To access the Archive directory, change
directory to pub/archive ("cd pub/archive"). The contents of the
archive may be listed by typing "ls".
------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Ex-
treme Ultraviolet Astrophysics, University of California, Berke-
ley. The opinions expressed are those of the authors. Publish-
ers: Roger F. Malina, C. Stuart Bowyer, Managing Editor: Camille
Trentacoste. Funded by NASA Contracts NAS5-30180 and NAS5-29298
Send newsletter correspondence to: pub@cea.berkeley.edu (Internet)
EUVE Public Archive via FTP: cea-ftp.cea.berkeley.edu, pub/archive
----------------------------------------------------------------
The EUVE Project is managed by NASA's GSFC. The Project Manager
at GSFC is Mr. Frank Volpe, the Project Scientist is Dr. Yoji
Kondo, the Deputy Project Scientist is Dr. Ronald Oliversen. The
NASA Headquarters EUVE Program Scientist is Dr. Robert Stachnik
the Deputy Program Scientist is Dr. Derek Buzasi, the Program
Manager is Mr. John Lintott. Information on the EUVE Guest
Observer Program is available from: Dr. Yoji Kondo, Mail Code 684
GSFC, Greenbelt, MD 20771 (301)286-6247; euve@stars.SPAN.NASA.GOV
|
| 770.14 | Update - August 23 | VERGA::KLAES | All the Universe, or nothing! | Fri Aug 28 1992 15:35 | 140 |
| Article: 1771
Newsgroups: sci.space.news
From: Roger "F." Malina <rmalina@cea.berkeley.edu>
Subject: EUV SKY SURVEY PROCEEDS SMOOTHLY
Sender: usenet@news.arc.nasa.gov
Organization: Center for EUV Astrophysics, University of California at Berkeley
Date: Sun, 23 Aug 1992 21:05:02 GMT
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY Vol 2, No.6 8/23/92
------------------------------------------------------------------
FIRST EUVE RESULTS TO BE SUMMARISED AT AUG 31 COSPAR TALK
---------------------------------------------------------
Bowyer and Malina will present an overview of the EUVE in orbit
performance and early scientific results at the COSPAR/ World
Space Congress Aug 31 In Washington DC. ( at 3pm in the
session on recent results in X ray and EUV astronomy, in the
Washington Convention Center)
EUVE SCIENCE TEAM MEETING DISCUSSES FIRST WEEK OF EUVE SKY SURVEY
-----------------------------------------------------------------
The data from the first week of the EUVE sky survey are now begining
to yield initial results which were discussed at the Aug 21 EUVE
Science Team meeting. A strip of sky 2 degrees wide was fully scanned
by EUVE during the first week of data taking. The first processing
revealed timing errors in the processing which resulted in position
errors in the resulting maps and catalogues. These timing and boresight
offsets have been now been corrected.
Following these corrections, the software pipeline has produced maps
and catalogues for the initial week of data. Sources were detected in
all of the 4 all sky survey filters. Only one of these is at the
location of a previously reported ROSAT WFC XUV source. Each reported
source is now being analysed in detail to eliminate spurious sources.
In several cases bright B stars were found to be detected because
of the UV light detected at the location of one of the known pin
holes in the EUVE filters. The software pipeline has now been
modified to remove from the data base all data collected when a star
is in the vicinity of a pin hole; this reprocessed data will be
available next week. Because of the preliminary nature of the
results of the processing of the first week of the sky survey, no
specific results will be mentioned in this newsletter. Let it
just be said that we are very very excited by the encouraging results.
EUVE CONSISTENTLY SEES HIGHER COUNT RATES THAN THE ROSAT WFC
------------------------------------------------------------
A comparison of count rates observed by EUVE for several hot white
dwarfs was presented, as compared with the similar Lexan (S1) filter
on the ROSAT WFC. EUVE was found to observe a count rate a factor of 3
higher than the ROSAT WFC for the EUVE all sky survey lexan channel,
and a fact of 5 higher for the EUVE deep survey Lexan channel.
One source analysed at this time for which EUVE has seen a lower
count rate than the ROSAT WFC lexan (S1) band is the AM Her type
cataclysmic variable RE 1938-461. Ground based optical data indicates
that the catclysmic variable is now much fainter optically than when
it was observed by ROSAT WFC.
EUVE PUBLIC ARCHIVE RELEASES SPECTRUM OF AU MIC
-----------------------------------------------
AU MIC was used as as an EUVE calibration target. AU MIC was seen to
flare during the observation and a bright emission line spectrum was
recorded. AU MIC was strongly detected in the short and medium
wavelength channels. The emission lines will be used to carry out
in-orbit wavelength calibration of the spectrometer. The EUVE public
archive has just released the raw uncalibrated spectrum of AU MIC. The
spectrum may be obtained from the public archive to aid Guest
Observers in planning their EUVE observations but may not be used for
scientific publications at this time. (similar data rights contraints
apply to all EUVE spectra releaed to date).
If you have not used the EUVE public archive you may obtain help by
sending email to archive@cea.berkeley.edu with a message containing
the word "help" (omit quotes) on the first line with no preceding
spaces. A file containing information will be returned to you
automatically.
EUVE PUBLIC ARCHIVE RELEASES RAW EUV SPECRUM OF EXTRAGALACTIC OBJECT
--------------------------------------------------------------------
The EUVE Public archive has released the raw uncalibrated spectrum of
the extragalactic object PKS 2155 -304. The source is detected
in the short wavelength spectrometer channel only.
EUVE ARCHIVE RELEASES MOON IMAGES IN THE EUV
--------------------------------------------
During the first week of August, the Moon was seen in all three of
EUVE's scanners. Hard-copy images are now available by sending
e-mail to archive@cea.berkeley.edu. Please be sure to include your
postal address with the request.
NEW EUVE DATA RIGHTS POLICY
---------------------------
A statement of the policy on data rights is now available
from the EUVE Public Archive via ftp. The file Datarights.txt
describes the proprietary limitations on three types of data:
(A) All sky survey scanner data, (B) Deep sky survey data
(including data from both the calibration and survey periods and
from the pointed observations), and (C) spectrometer data (i.e.,
spectra used to calibrate the spectrometer). This file will be
updated with the latest information on EUVE data rights. For further
information or clarification on the EUVE data rights policy, please
contact the EUVE Project Scientist Dr Yoji Kondo.
EUVE CARRIES OUT DAY-TIME DATA TAKING TEST
--------------------------------------------
A test was carried out to establish EUVE count rates observed during
the day time by each detector. As a result of this test the EUVE
orbital night time data taking has been redefined to be 13% longer
because count rates were low enough to assure quality data. Further
tests are planned to determine which detectors could be operated
safely during orbital day time.
------------------------------------------------------------------
------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Ex-
treme Ultraviolet Astrophysics, University of California, Berke-
ley. The opinions expressed are those of the authors. Publish-
ers: Roger F. Malina, C. Stuart Bowyer, Managing Editor: Camille
Trentacoste. Funded by NASA Contracts NAS5-30180 and NAS5-29298
Send newsletter correspondence to: pub@cea.berkeley.edu (Internet)
EUVE Public Archive via FTP: cea-ftp.cea.berkeley.edu, pub/archive
----------------------------------------------------------------
The EUVE Project is managed by NASA's GSFC. The Project Manager
at GSFC is Mr. Frank Volpe, the Project Scientist is Dr. Yoji
Kondo, the Deputy Project Scientist is Dr. Ronald Oliversen. The
NASA Headquarters EUVE Program Scientist is Dr. Robert Stachnik
the Deputy Program Scientist is Dr. Derek Buzasi, the Program
Manager is Mr. John Lintott. Information on the EUVE Guest
Observer Program is available from: Dr. Yoji Kondo, Mail Code 684
GSFC, Greenbelt, MD 20771 (301)286-6247; euve@stars.SPAN.NASA.GOV
------------------------------------------------------------------END
|
| 770.15 | EUVE finds what it is looking for | VERGA::KLAES | All the Universe, or nothing! | Thu Sep 24 1992 16:15 | 117 |
| Article: 1848
Newsgroups: sci.space.news
From: yee@trident.arc.nasa.gov (Peter E. Yee)
Subject: NASA satellite detects new, extreme ultraviolet sources
[Release 92-138] (Forwarded)
Sender: usenet@news.arc.nasa.gov
Organization: NASA Ames Research Center, Moffett Field, CA
Date: Thu, 3 Sep 1992 19:51:49 GMT
Michael Braukus
Headquarters, Washington, D.C. August 31, 1992
(Phone: 202/358-0872)
Randee Exler
Goddard Space Flight Center, Greenbelt, Md.
(Phone: 301/286-7277)
RELEASE: 92-138
NASA SATELLITE DETECTS NEW, EXTREME ULTRAVIOLET SOURCES
An object emitting extreme ultraviolet light located outside the Milky
Way galaxy was detected by a NASA satellite through interstellar gas and dust,
once thought to block this source of radiation. This discovery assures that
astronomers will have a new tool to probe the universe.
Also, EUVE has detected a new source of extreme ultraviolet radiation
(EUV) from the corona of a star much like the sun, located about 16 light
years from Earth. A white dwarf companion star also appears in the
photograph released today.
On July 8 and 9, NASA's Extreme Ultraviolet Explorer (EUVE)
measured an outburst from a "cataclysmic variable," a closely orbiting pair of
stars in which gravitational forces pull matter from the outermost layers of a
normal star onto the surface of a white dwarf companion. The hot,
compressed stellar material generates an explosive burst of extreme
ultraviolet radiation as the material falls into the deep gravitational
field of the white dwarf.
Other explosive events are flares on stars. These are unpredictable,
giant versions of eruptions known to occur on a smaller scale on our own sun.
EUVE caught two such events on the red dwarf stars called AT Microscopium
and AU Microscopium.
Also, EUVE astronomers were surprised when they detected an object
located outside our own Milky Way galaxy that was emitting extreme
ultraviolet radiation (EUV). At one time, astronomers had thought that the
interstellar medium, the gas and dust spread throughout the galaxy,
effectively would block their view of even nearby objects, because it is highly
opaque to EUV radiation.
Each first view in a new spectral band gives astronomers a new tool to
probe the universe. The EUV window is one of the last unexplored spectral
regions.
EUVE Principal Investigators Professor Stuart Bowyer and Dr. Roger
Malina, of the University of California at Berkeley's Center for Extreme
Ultraviolet Astrophysics (CEA), presented the findings today to space
scientists at the World Space Congress in Washington, D.C.
According to Professor Bowyer, initiator of the EUV program at
Berkeley, "Years ago a lot of our colleagues thought we were crazy to observe
in the EUV. Everyone "knew" that trying to look through the interstellar
medium at these wavelengths would be like trying to use a telescope in a San
Francisco fog."
Extreme ultraviolet (EUV) radiation is visible only to instruments
above Earth's atmosphere. Radiation at these energies is emitted by
multi-million degree coronae on stars, by giant eruptions on novae, by the hot
surfaces of white dwarfs and by other exotic sources in the cosmos.
The EUVE was launched June 7, 1992, to study the extreme ultraviolet,
the part of the electromagnetic spectrum lying between optical and x-ray
wavelengths. It represents NASA's 67th Explorer mission. The first Explorer
was launched on Jan. 31, 1958, and it discovered the Van Allen radiation
belts.
The EUVE satellite, now 6 weeks into a survey of the entire sky, will
provide astronomers with their first detailed maps in multiple EUV energy
bands.
Officials at NASA's Goddard Space Flight Center, Greenbelt, Md., report
that the satellite has functioned smoothly since its launch. All instruments
are performing at or above expected levels, and data analysis is 50-percent
ahead of schedule.
The EUVE Science Operations Center, based at CEA, operates around
the clock, sending commands to point the instruments at selected
astronomical sources and recording the findings of the satellite's four
telescopes and three spectrometers. The CEA has adopted a novel approach
for operating the project with a staff that includes more than two dozen
undergraduate students who are getting a unique hands-on educational
experience.
Researchers and engineers are studying the calibration and check-out
data obtained during the first 6 weeks of the mission. These data serve a dual
purpose. They verify the instrument performance and at the same time, give
astronomers valuable new measurements to test their models.
NASA's Guest Observer Program begins at the conclusion of the
6-month sky survey. Scientists from around the world have applied to NASA
to use the capabilities of the EUVE spectrometers. Stiff competition will
assure that only the very best of the 140 submitted proposals will result in
allocated observing time.
Goddard is responsible for the design, construction, integration,
checkout and operation of EUVE. The spacecraft's science instrumentation
was designed, constructed and calibrated by the Space Science Laboratories
of the University of California, Berkeley. The EUVE is managed by Goddard
for NASA's Office of Space Science and Applications, Washington, D.C.
Editors Note: A photograph is available to media representatives by
calling NASA's Broadcast And Imaging Branch on 202/453-8373.
Color B&W
92-HC-597 92-H-653
|
| 770.16 | Update - September 19 | VERGA::KLAES | All the Universe, or nothing! | Thu Sep 24 1992 17:21 | 144 |
| From: DECWRL::"rmalina@cea.berkeley.edu" "Roger 'F.' Malina" 20-SEP-1992
20:12:01.18
To: sci-space-news@ames.arc.nasa.gov
CC:
Subj: EUVE news
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY Vol 2, No. 7 9/19/92
------------------------------------------------------------------
EUVE SKY SURVEY PROCEDING SMOOTHLY
----------------------------------
The 100th day of the EUVE mission was just celebrated. The EUVE
all sky survey continues to be carried out smoothly. Initial
processing of the first 16 days of the sky survey has been carried out
and initial lists of possible EUVE sources have been released internally
to the EUVE Science Team. The large number of new EUV sources are being
screened for spurious sources, and optical counterpart identification
work has begun.
ALPHA CEN AND PROX CEN
----------------------
Initial results on EUVE observations of ALpha Centaurus and Prox
Cen were presented to the EUVE Science Team. Both sources are
strongly detected, and includes detections in all four EUVE filters.
The detection in all four EUVE filters is very encouraging and indicate
that spectroscopy will be possible to very long wavelengths.
For further information contact Dr Peter Vedder: pvedder@cea.berkeley.edu
REPROCESSED CALIBRATION SPECTRA OF WHITE DWARFS
-----------------------------------------------
The data from calibration white dwarfs WD 2309+105 and WD 1845 +019
have been reprocessed revealing that a number of unexpected spectral
features will be useful for wavelength calibration, in addition to
the use of these sources as photometric standards. The detection of these
new spectral features is generating much excitement.The raw calibration
spectra will be released shortly through the public archive.
GEOMAGNETIC STORMS LEAD TO ENHANCED BACKGROUNDS
-----------------------------------------------
Dr Randy Gladstone reported that during the recent major solar
storms and associated geomagnetic storms, the Scanner A and B
detectors experienced very enhanced detector backgrounds of
above 1000 c/s. The data from these periods will lead to data
gaps that will have to be filled in during the second six month
phase of the mission. Further information from rgladstone@ssl.berkeley.edu
BLIND TASTE TESTING OF SOURCE DETECTION ALGORITHMS UNDER WAY
------------------------------------------------------------
EUVE BUDGET CUTS TO REDUCE PLANS FOR EUVE DATA ANALYSIS
------------------------------------------------------------
We are currently comparing the results of four different source
detection algorithms which are being run on the same data set from the
first 16 days of the sky survey. The results will be reviewed next
week to see which algorithms detect the largest number of EUV point
sources in the data and which ones have the lowest spurious source
detection rates. The winning code from this competition will be used
for subsequent reprocessing of the all sky survey data. Due to the
large cuts in the EUVE post launch budgets, release of the monthly
EUVE bright source lists and catalogues will not be carried out and
development of the EUVE diffuse sky maps has been put on hold. The
total impact of the budget cuts are still being assessed.
Summary of cross-comparisons of EUVE, EXOSAT, and ROSAT WFC calibrations
---------------------------------------------------------------------------
The EUVE in-flight calibration verification program includes folding
white dwarf models through the EUVE instrument effective areas, and
choosing parameters which give predicted count rates which match the
observed count rates. We will also be intercomparing observations
taken with the EUVE scanners, deep survey and spectrometer on the same
objects. The same models which fit the EUVE observations are then used
to compare predicted and measured count rates for the ROSAT WFC and
for EXOSAT in the cases in which EXOSAT and ROSAT WFC data are
available. The EUVE all sky survey is also being interrupted once a
month to carry out calibrations to monitor any change in EUVE
instrument performance.
In the case of CD -38 10980 (WD 1620-391), a ~24,000 K DA
white dwarf observed with the EUVE Deep Survey instrument, the same
pure hydrogen model fits both the EUVE Deep Survey Lexan and the WFC
S1 and S2 count rates to within a few percent.
In the case of WD 1845+019, which is somewhat hotter, the flux
peak is at 150 Angstroms, and significant flux is present up to 300
Angstroms. For this object, the agreement between EUVE and the WFC is
not as good as for WD 1620-391. The model which best fits EUVE Deep
Survey Lexan/B count rate overpredicts the WFC S1 and S2 countrates by
about 20%. A model can be selected which underpredicts EUVE by 10% and
overpredicts ROSAT WFC count rates by 10%. However, we are now
investigating why the EUVE vs WFC comparisons differ for objects with
different flux distributions.
Initial discrepancies with the ROSAT WFC observations have been
reduced through the use of the recent amended ROSAT WFC instrument
calibration curves which we have now received and also taking into
account the degradation curves provided for the drop of sensitivity
during the ROSAT WFC survey. We are still finding discrepancies with
the EXOSAT Al/P observations as models which fit the EUVE data
overpredict the count rates reported by EXOSAT by at least 50%. This
is still being investigated. Observed countrates by EUVE are a factor
of ~3 higher than ROSAT WFC S1 for the same objects due to the larger
grasp of the EUVE filters.
For further information on the EUVE calibration analysis contact
Dr David Finely and Dr Pat Jelinksy at david@cea.berkeley.edu
EUVE ARCHIVE ADDITIONS AND UPDATES
----------------------------------
New files have been added to the EUVE Public Archive. To access the
EUVE Public Archive for the first time send email to
archive@cea.berkeley.edu with the word 'help' on the first line Now
Available in Hardcopy form only:
-----------------------------------
1)Scanner A deep exposure showing calibration target WD 1254+223
2)Scanner B calibration pointing showing WD1254+223,
Also:
Updated Datarights document: clarification of all sky survey data rights
Updated EUVE_bibs document: new available publications
------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Ex-
treme Ultraviolet Astrophysics, University of California, Berke-
ley. The opinions expressed are those of the authors. Publish-
ers: Roger F. Malina, C. Stuart Bowyer, Managing Editor: Camille
Trentacoste. Funded by NASA Contracts NAS5-30180 and NAS5-29298
Send newsletter correspondence to: pub@cea.berkeley.edu (Internet)
EUVE Public Archive via FTP: cea-ftp.cea.berkeley.edu, pub/archive
----------------------------------------------------------------
The EUVE Project is managed by NASA's GSFC. The Project Manager
at GSFC is Mr. Paul Pashby, the Project Scientist is Dr. Yoji
Kondo, the Deputy Project Scientist is Dr. Ronald Oliversen. The
NASA Headquarters EUVE Program Scientist is Dr. Robert Stachnik
the Deputy Program Scientist is Dr. Derek Buzasi, the Program
Manager is Dr. Guenter Riegler. The Project Operations Director
is Mr. Kevin Hartnett. Information on the EUVE Guest Observer
Program is available from: Dr. Yoji Kondo, Mail Code 684 GSFC,
Greenbelt, MD 20771 (301)286-6247; euve@stars.SPAN.NASA.GOV
|
| 770.17 | Update - October 6 | VERGA::KLAES | All the Universe, or nothing! | Wed Oct 07 1992 16:56 | 94 |
| Article: 2142
Newsgroups: sci.space.news
From: rmalina@ssl.Berkeley.Edu (Roger F. Malina)
Subject: EUVE Progress Report [10/06/92]
Sender: usenet@news.arc.nasa.gov
Organization: Center for EUV Astrophysics, University of California at Berkeley
Date: Tue, 6 Oct 1992 23:32:11 GMT
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
------------------------------------------------------------------
Vol 2, No.8 10/6/92 ISSN 1065-3597
------------------------------------------------------------------
EUVE SURVEY CONTINUES
---------------------
The EUVE all sky survey is continuing smoothly. Some operational
problems were encountered last weekend due to loss of contact to the
spacecract. As a result the one month calibration period was extended.
Any resulting gap in the sky survey will be filled in during the
second six month gap filling period.
The "detection" software taste test is runnign smoothly. All four
independent detection schemes have been used to generate source lists
on the first 22 days of the survey. The results are being intercompared.
Optical identification of the new sources is proceeding.
PKS 2155
--------
Herman Marshall presented new results on PKS 2155 to the science team.
The lack of observed variability is very unexpected due to the known x
ray and uv variability. In addition studies of the polarization of PKS
2155 are under way.
Background Features
-------------------
Randy Gladstone reported on unexpected periods of high charged
particle background at night over Australia. These may be due to
military radars causing precipitation of particles.
EUVE ARCHIVE ADDITIONS AND UPDATES
----------------------------------
New files have been added to the EUVE Public Archive.
If you have not used the EUVE public archive you may obtain help by
sending email to archive@cea.berkeley.edu with a message containing
the word "help" (omit quotes) on the first line with no preceding
spaces. A file containing information will be returned to you
automatically.
Updated EUVE_bibs document: new available publications
EUVE PUBLIC ARCHIVE RELEASES 2 NEW WHITE DWARF SPECTRA
The EUVE Public archive has released the background subtracted spectra
of the white dwarf stars WD1845+019 and WD2309+105 in the short, medium,
and long wavelength spectrometer. These spectra show unexpected absorption
features newar 206A which will be used as a new calibration point.
EUVE to be featured on NASA Select
----------------------------------
NASA will feature the new results from EUVE on the October 8 NASA
Select Astronomy update.
------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Ex-
treme Ultraviolet Astrophysics, University of California, Berke-
ley. The opinions expressed are those of the authors. Publish-
ers: Roger F. Malina, C. Stuart Bowyer, Managing Editor: Camille
Trentacoste. Funded by NASA Contracts NAS5-30180 and NAS5-29298
Send newsletter correspondence to: pub@cea.berkeley.edu (Internet)
EUVE Public Archive via FTP: cea-ftp.cea.berkeley.edu, pub/archive
----------------------------------------------------------------
The EUVE Project is managed by NASA's GSFC. The Project Manager
at GSFC is Mr. Paul Pashby, the Project Scientist is Dr. Yoji
Kondo, the Deputy Project Scientist is Dr. Ronald Oliversen. The
NASA Headquarters EUVE Program Scientist is Dr. Robert Stachnik
the Deputy Program Scientist is Dr. Derek Buzasi, the Program
Manager is Dr. Guenter Riegler. The Project Operations Director
is Mr. Kevin Hartnett. Information on the EUVE Guest Observer
Program is available from: Dr. Yoji Kondo, Mail Code 684 GSFC,
Greenbelt, MD 20771 (301)286-6247; euve@stars.SPAN.NASA.GOV
|
| 770.18 | EUVE examines galaxy 2 billion light years distant | VERGA::KLAES | All the Universe, or nothing! | Fri Oct 09 1992 14:50 | 162 |
| Article: 2159
Newsgroups: sci.space.news
From: yee@trident.arc.nasa.gov (Peter E. Yee)
Subject: NASA spacecraft "sees" object 2 billion light years away
[Release 92-169] (Forwarded)
Sender: usenet@news.arc.nasa.gov
Organization: NASA Ames Research Center, Moffett Field, CA
Date: Thu, 8 Oct 1992 21:39:15 GMT
Mike Braukus
Headquarters, Washington, D.C. October 8, 1992
(Phone: 202/358-0872)
Dolores Beasley
Goddard Space Flight Center, Greenbelt, Md.
(Phone: 301/286-2806)
Dr. Bernhard Haisch
Center for Extreme Ultraviolet Astrophysics
University of California, Berkeley
(Phone: 510/643-5639)
RELEASE: 92-169
NASA SPACECRAFT "SEES" OBJECT 2 BILLION LIGHT YEARS AWAY
A powerful, exotic object 2 billion light-years beyond the Milky Way
galaxy has been observed by astronomers using a new NASA spacecraft
designed to detect radiation in the little-explored extreme ultraviolet
portion of the electromagnetic spectrum.
"Twenty years ago no one would have believed you could see out of the
solar system at EUV wavelengths. But now -- for the first time -- we
actually have obtained a EUV spectrum for an object beyond our galaxy,"
said Dr. Ed Weiler, Chief of NASA's Ultraviolet and Visible Astrophysics
Branch.
The radiation source was observed by the Extreme Ultraviolet Explorer
(EUVE) Spacecraft, launched into Earth orbit on June 7 to search the
spectrum between visible light and x-rays.
Observation of the EUV spectrum both inside and out of the Milky Way
galaxy is often blocked by gas and dust in interstellar space. However, the
distribution of the gas and dust is uneven which allows the EUVE
telescopes to see distant sources of radiation.
According to the EUVE science team, the object is a tremendously
energetic elliptical galaxy that radiates as much energy as a trillion suns.
Some astrophysicists think such a galaxy, called a "BL Lac Object," may
contain at its center a super-sized black hole with a mass of 100 million
suns and may be a cousin to the even more mysterious quasars.
The science team is headed by Prof. Stuart Bowyer and Dr. Roger
Malina at the University of California-Berkeley Center for Extreme
Ultraviolet Astrophysics.
BL Lac Objects, like PKS 2155-304, vary dramatically in brightness in
all other spectral regions. Now scientists have discovered that it was rock
steady in the EUV for a day and a half, according to Dr. Herman Marshall,
EUVE astronomer.
"This result is extremely interesting, but we would like more
observations to confirm this," said Goddard's Dr. Yoji Kondo, EUVE Project
Scientist.
"But it might be that we have found the right window, as Dr. Marshall
has indicated, to see the steady infall of material onto the giant black hole
that the theorists think may be at the very center of this object," said Dr.
Kondo.
The EUVE satellite is now 11 weeks into a survey of the entire sky. It
will provide astronomers with their first detailed maps in several EUV
energy bands. Radiation at these energies is emitted by multi-million
degree coronae on stars, by giant eruptions on novae, by the hot surfaces
of white dwarfs and by other exotic sources in the cosmos such as the BL
Lac object.
Other Observations
One of the new EUV sources detected by the satellite early in the
mission was the corona of a star much like the sun, located about 16 light-
years away from Earth. A white dwarf companion 7 arc-minutes away also
appears in the EUV image.
On July 8-9, an outburst was observed from a cataclysmic variable, RE
1938-461, a closely orbiting pair of stars in which gravitational forces pull
matter from the outermost layers of one star onto the surface of the other,
a white dwarf companion. The hot compressed stellar material generates
an explosive burst of EUV radiation as it falls into the deep gravitational
field of the white dwarf.
Other explosive events are flares on stars. These are unpredictable,
giant versions of eruptions known to occur on a much smaller scale on the
sun. The EUVE caught two such events on the red dwarf stars AT Mic and
AU Mic.
Spacecraft, Operations Performing Fine
All instruments are performing at or above expected levels,
according to instrument Principal Investigator Roger Malina. The EUVE
Science Operations Center, based at CEA, operates around the clock,
sending commands to point the instruments at selected astronomical
sources and recording the findings of the satellite's four telescopes
and three spectrometers.
A novel feature is that the staff includes more than two dozen
undergraduate students who are getting a unique hands-on educational
experience.
Researchers and engineers in Berkeley are pouring over the calibration
and check-out data obtained during the first 6 weeks of the mission.
These data serve a dual purpose. They verify the instrument performance
and at the same time, give astronomers valuable, new measurements to
test their models.
The EUVE Project is managed by the NASA Goddard Space Flight
Center, Greenbelt, Md., for the Office of Space Science and Applications,
Washington, D.C.
NOTE TO EDITORS: Three photographs are available to news media to
accompany this release by calling the NASA Headquarters Broadcast and
Imaging Branch at 202/453-8375:
Color B&W
HR 6094 92-HC-597 92-H-728
EUV Spectrum of (no color) 92-H-729
AU Microscopii
PKS 2155-304 92-HC-673 92-H-730
A videotape to accompany this release containing an interview with Dr.
Stuart Bowyer and Local Bubble animation also is available at the
Broadcast and Imaging Branch.
Article: 2150
Newsgroups: sci.space.news
From: baalke@kelvin.jpl.nasa.gov (Ron Baalke)
Subject: GSFC Monthly Status Reports
Sender: news@elroy.jpl.nasa.gov (Usenet)
Organization: Jet Propulsion Laboratory
Date: Thu, 8 Oct 1992 05:51:45 GMT
Goddard Monthly Public Affairs Status Report, September 1992
EUVE Extreme Ultraviolet Explorer
EUVE: All EUVE instruments are performing at or better than
expected levels. The satellite is now 11 weeks into a survey of the
entire sky which will provide astronomers with their first detailed
maps in several EUV energy bands. NASA's Guest Observer program
will begin at the conclusion of the sky survey in Freshman 1993.
EUVE was launched June 7, 1992 from Cape Canaveral Air Force Station
onboard a Delta II rocket.
Contact: Dolores Beasley (301) 286-2806.
___ _____ ___
/_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov
| | | | __ \ /| | | | Jet Propulsion Lab |
___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Einstein's brain is stored
/___| | | | ___/ | |/__ /| Pasadena, CA 91109 | in a mason jar in a lab
|_____|/ |_|/ |_____|/ | in Wichita, Kansas.
|
| 770.19 | Updates - November 25 to December 14 | VERGA::KLAES | I, Robot | Fri Dec 11 1992 15:26 | 453 |
| Article: 2615
Newsgroups: sci.space.news
From: Roger "F." Malina <rmalina@cea.berkeley.edu>
Subject: new euve news
Sender: usenet@news.arc.nasa.gov
Organization: Center for EUV Astrophysics, University of California at Berkeley
Date: Wed, 9 Dec 1992 05:57:48 GMT
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
------------------------------------------------------------------
Vol 2, No. 10 11/25/92 ISSN 1065-3597
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Internal Release of first EUVE bright source list
---------------------------------------------------
The first official list of bright EUVE sources was released internally
to the EUVE project at UCB. This list covers the first 16 days of the
sky survey. The list was compiled from 163 sources detected using the
"code B" detection algorithm ; the data from each detected source was
examined visually to screen out spurious or posibly spurious sources.
This was achieved by convolving the images with the point spread
function observed from the very bright EUV source Feige 24 and
eliminating sources of suspect morphology or significance.
This screening resulted in a final list of 49 definite sources and an
additional 59 sources which are being analysed further.
The 49 definite sources have been compiled into the first EUVE bright
source list. Classes of sources in this first list include hot white
dwarfs, planetary nebula, RsCVns, flare stars, cool star coronae,
solar analogs and B stars. Of the list of 49, 20 sources had no
immediate optical counterparts and have been handed over to the
optical identification subgroup for optical identification.
A careful comparison with the ROSAT WFC bright source list indicates
that for the same sky area at low ecliptic latitude (<60deg) the EUVE
bright source list had 28 definite sources, ROSAT WFC reported 10
bright sources of which 7 were detected by EUVE.
Prox Cen Flare observed by EUVE: a very small flare
---------------------------------------------------
Dr Peter Vedder reported to the EUVE science team that an EUV flare
was recently detected on Prox Cen. The maximum flare intensity was
approx 10(27) ergs/sec; this flare was well detected and is of
particular interest because of its low intensity which compares with
the energetic of solar flares and will permit direct solar flare
comparisons. For Further information contact pvedder@cea.berkeley.edu
EUVE monitors flare on CV VW Hyi during outburst
------------------------------------------------
By serendipity EUVE monitored the cataclysmic variable VW Hyi during
its recent "normal" outburst . The outburst was monitored for EUVE by
the AAVSO. Analysis of the EUV data is underway. For futher
information contact John Vallerga at jvv@cea.berkeley.edu
Erratum: UZ For
---------------
In the previous newsletter the EUVE detection of the Cataclysmic
Variable UZ For was reported. We noted that UZ For was not detected by
the ROSAT WFC - we have been informed that the reason that UZ For was
not in the ROSAT Bright source list was that it is located in a gap
of sky not covered by ROSAT WFC for the ROSAT WFC Bright Source List.
The EUVE detection is still firm.
Happy Thanksgiving
------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Ex-
treme Ultraviolet Astrophysics, University of California, Berke-
ley. The opinions expressed are those of the authors. Publish-
ers: Roger F. Malina, C. Stuart Bowyer.Funded by NASA Contracts
NAS5-30180 and NAS5-29298.
Send newsletter correspondence to: carlos@cea.berkeley.edu (Internet)
EUVE Public Archive via FTP: cea-ftp.cea.berkeley.edu, pub/archive
----------------------------------------------------------------
The EUVE Project is managed by NASA's GSFC. The Project Manager
at GSFC is Mr. Paul Pashby, the Project Scientist is Dr. Yoji
Kondo, the Deputy Project Scientist is Dr. Ronald Oliversen. The
NASA Headquarters EUVE Program Scientist is Dr. Robert Stachnik
the Deputy Program Scientist is Dr. Derek Buzasi, the Program
Manager is Dr. Guenter Riegler. The Project Operations Director
is Mr. Kevin Hartnett. Information on the EUVE Guest Observer
Program is available from: Dr. Yoji Kondo, Mail Code 684 GSFC,
Greenbelt, MD 20771 (301)286-6247; euve@stars.SPAN.NASA.GOV
Article: 2624
Newsgroups: sci.space.news
From: Roger "F." Malina <rmalina@cea.Berkeley.EDU>
Subject: new euve news - dec 9
Sender: usenet@news.arc.nasa.gov
Organization: Center for EUV Astrophysics, University of California at Berkeley
Date: Wed, 9 Dec 1992 06:04:13 GMT
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
------------------------------------------------------------------
Vol 2, No. 11 12/9/92 ISSN 1065-3597
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TWO NEW EXTRAGALACTIC EUVE SOURCES DISCOVERED
--------------------------------------------
Herman Marshall announced to the EUVE science team the discovery
of two new EUVE extragalactic sources from analysis of the first
22 days of the EUVE sky survey. Both were detected in the
EUVE Lexan filter.
SECOND RELEASE OF EUVE BRIGHT SOURCE LIST
_________________________________________
Bob Patterer presented the second release of the internal EUVE
Bright Source List to the science team. This release covers
the first 22 days of the sky survey and includes some new sources
for the first 16 day period. The total number of definite
sources for the first 22 days stands at 59, with a large number of
possible sources being analysed further. Optical ID work
has begun with Dr Dopita and Dr Shara for sources with no
immediate optical counterparts.
An analysis of the relative counts of sources in the 4 separate
EUVE catalogues ( one for each bandpass) is under way. For the
period under analysis 36 definite sources were detected in the
Lexan (100A) filter, 18 in the Al/C (200 A), 8 in the
"Dagwood" filter (400A) and 8 in the Tin (600 A) filter.
NO DEGRADATION IN EUVE PERFORMANCE DETECTED IN ORBIT SO FAR
___________________________________________________________
David Finley and Jean Dupuis presented preliminary analysis of
in orbit calibration data for the calibration white dwarf WD 2309.
This source has now been re-observed twice during the sky survey
no change in flux was detected to within a few percent indicating
that the instrument sensitivity is stable.
VW Hyi WAS OBSERVED DURING FLARE
________________________________
John Vallerga confirmed that the CV VW Hyi as detected during
the "normal" flare during the outburst reported by the AAVSO.
EUVE COOL STAR DATA INTERPRETED
_______________________________
Dr Alex Brown gave a seminar at CEA in which EUVE data on
cool stars was discussed. Of particular note is that the
data on the corona of alpha Cen ( Vedder et al in prep)
shows that the emission measure distribution as a function
of temperature is much steeper than previous analyses of
coronae had concluded.
EUVE ARCHIVE RELEASES SPECTRUM OF FEIGE 24
------------------------------------------
The DA white dwarf Feige 24 was recently observed by the EUVE for
wavelength and boresight calibration purposes. The Archive is now
pleased to announce the release of a preliminary extraction of the
spectrum of Feige 24 from the medium wavelength spectrometer, which
covers a wavelength range of approximately 140-380 Angstroms. The
exposure time of the observation was about 45000 seconds.
The following list summarizes the EUVE spectral data released by the
Archive to date: Approved Guest Observers interested in the dates for
release of other calibration spectra should contact the archive.
continuum_source.spec: continuum source spectrum for WD1620-391
from short wavelength spectrometer;no aspect
correction has been applied
filteredge_source.spec: EUVE continuum source showing 170A
filter edge and background counts
AUMIC_SW.spec: short wavelength spectrum of the late type star
AU Mic
AUMIC_SW.spec: medium wavelength spectrum of the late type star
AU Mic
AUMIC_SW_FLARE.spec: short wavelength spectrum of the late type star
AUMIC during flare outburst
AUMIC_SW_QUIET.spec: short wavelength spectrum of the late type star
AUMIC in quiescence
PKS2155-304_SW.spec: short wavelength spectrum of the extragalactic source
PKS 2155-304
WD1845+019_LW.spec: long wavelength spectrum of the DA-type star
WD1845+019
WD1845+019_MW.spec: medium wavelength spectrum of the DA-type star
WD1845+019
WD1845+019_SW.spec: short wavelength spectrum of the DA-type star
WD1845+019
WD2309+105_LW.spec: long wavelength spectrum of the DA-type star
WD2309+105
WD2309+105_MW.spec: medium wavelength spectrum of the DA-type star
WD2309+105
WD2309+105_SW.spec: short wavelength spectrum of the DA-type star
WD2309+105
MCT2020-4234_SW.spec: short wavelength spectrum of the DA-type star
MCT2020-4234
FEIGE24_MW.spec: medium wavelnegth spectrum of the hot DA-type star
Feige 24
If you have not used the EUVE public archive, you may obtain help by
sending e-mail to archive@cea.berkeley.edu with a message containing
the word "help" (omit quotes) on the first line of the main body of
the text (ie not in the subject field), with no preceding spaces. A
file containing information will be returned to you automatically.
Jeremy Drake, EUVE Archive Scientist
------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Ex-
treme Ultraviolet Astrophysics, University of California, Berke-
ley. The opinions expressed are those of the authors. Publish-
ers: Roger F. Malina, C. Stuart Bowyer.Funded by NASA Contracts
NAS5-30180 and NAS5-29298.
Send newsletter correspondence to: carlos@cea.berkeley.edu (Internet)
EUVE Public Archive via FTP: cea-ftp.cea.berkeley.edu, pub/archive
----------------------------------------------------------------
The EUVE Project is managed by NASA's GSFC. The Project Manager
at GSFC is Mr. Paul Pashby, the Project Scientist is Dr. Yoji
Kondo, the Deputy Project Scientist is Dr. Ronald Oliversen. The
NASA Headquarters EUVE Program Scientist is Dr. Robert Stachnik
the Deputy Program Scientist is Dr. Derek Buzasi, the Program
Manager is Dr. Guenter Riegler. The Project Operations Director
is Mr. Kevin Hartnett. Information on the EUVE Guest Observer
Program is available from: Dr. Yoji Kondo, Mail Code 684 GSFC,
Greenbelt, MD 20771 (301)286-6247; euve@stars.SPAN.NASA.GOV
Article: 2618
Newsgroups: sci.space.news
From: carlos@ssl.Berkeley.Edu (Carlos Lemus)
Subject: EUVE news for 11/12/92
Sender: usenet@news.arc.nasa.gov
Organization: Center for EUV Astrophysics, University of California at Berkeley
Date: Wed, 9 Dec 1992 06:00:17 GMT
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
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Vol 2, No. 9 11/12/92 ISSN 1065-3597
------------------------------------------------------------------
The following EUVE results will be presented at the January 1993
meeting of the AAS. If you are interested in more details, please
contact the lead author of each paper ( send to (author first initial
author last name)@cea.berkeley.edu) or to rmalina@cea.berkeley.edu
and I will forward to query to the right person.
EUVE Observations of Hot DA White Dwarfs, D.\|S. Finley, J. Dupuis,
F. Paerels, and D. Koester
Wavelength and Throughput Calibration of the EUVE
Spectrometer from In-Orbit Observations, M. Abbott, J. Dupuis,
C.\|A. Christian, P. Jelinsky, and D.\|S. Finley
Extreme Ultraviolet Emission from Late-Type Stars: Early Results
from EUVE, P.\|W. Vedder, R.\|J. Patterer, J. Drake, P.
Jelinsky, A. Brown, and S. Bowyer
Processing Techniques in the Reduction and Analysis of
EUVE Spectrometer Observations, C.\|A. Christian, M. Abbott,
J. Dupuis, P. Jelinsky, and D.\|S. Finley
EUVE Observations of the Magnetic Cataclysmic Variable RE1938-461,
J.\|K. Warren, J.\|V. Vallerga, C.\|W. Mauche, K. Mukai, O. Siegmund
Scheduling the 1st Year of EUVE Guest Observer Targets,
C.\|A.\|Dobson, M. Johnston, M.\|E. Samuel, P. Jelinsky, C.\|A. Christian,
and D. Biroscak
The Influence of Rotation, Mass, Age and Evolutionary Phase on the
EUV Luminosities of Late-Type Stars: First Results from the EUVE
All-Sky Survey, J.\|J. Drake, R.\|J. Patterer,
P.\|W. Vedder, P. Jelinsky, A. Brown, and S. Bowyer,
EUVE Deep Survey Observations of a Large Flare on AU Mic, S.\|L.
Cully, O.\|H.\|W. Siegmund, G. Basri, P.\|W. Vedder, J.\|V. Vallerga
An Overview of the Performance of the EUVE Observatory, R.\|F.
Malina, S. Bowyer, M. Abbott, C.\|A. Christian, J. Drake,
J. Dupuis, D.\|S. Finley, A. Fruscione, I. Hawkins, P. Jelinsky,
R. Lieu, H.\|L. Marshall, R.\|J. Patterer, J.\|V. Vallerga, P.\|W.
Vedder, and S. Vennes,
EUVE Observations of RS CVn Systems, R.\|J. Patterer, P.\|W. Vedder,
J.\|J. Drake, P. Jelinsky, A. Brown, and S. Bowyer,
The EUVE All-Sky Survey and Bright Source
Catalog, A. Fruscione, S. Bowyer, R.\|F. Malina, J.\|J. Drake,
D.\|S. Finley, I. Hawkins, P. Jelinsky, R. Lieu, H.
Marshall, R.\|J. Patterer, J.\|V. Vallerga, P.\|W. Vedder, Vennes
Spectroscopic Observations of the Interstellar Medium in Emission in
the Extreme Ultraviolet: Early results from EUVE, P. Jelinsky,
J.\|V. Vallerga, J. Edelstein, and S. Bowyer
The EUVE Archive, I. Hawkins,
C.\|A. Dobson, C.\|A. Christian,
J.\|J. Drake, R.\|F. Malina, E. Polomski, and K. Chen
Interstellar Medium Continuum, Autoionization, and Line Absorption
in the Extreme Ultraviolet, T. Rumph, S. Bowyer, and S. Vennes
Accretion and Diffusion in the Atmosphere of the
V471 Tauri's White Dwarf, J. Dupuis, S. Vennes, and S. Bowyer
Observations of PKS 2155-304 with EUVE, H.\|L. Marshall, T.\|E.
Carone, A. Fruscione, and P. Jelinsky
EUVE Broadband Detection of the Diffuese Sky Background, R. Lieu, S.
Bowyer, J. Edelstein, and P. Jelinsky
EUVE Observations of the He-Rich DO White Dwarf MCT 0501-298:
Evidence for Very Low ISM Column Density, S. Vennes, P. Jelinsky, A.
Wiercigroch, S. Bowyer, R.\|F. Malina, G. Fontaine, and F. Wesemael,
------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Ex-
treme Ultraviolet Astrophysics, University of California, Berke-
ley. The opinions expressed are those of the authors. Publish-
ers: Roger F. Malina, C. Stuart Bowyer.Funded by NASA Contracts
NAS5-30180 and NAS5-29298.
Send newsletter correspondence to: carlos@cea.berkeley.edu (Internet)
EUVE Public Archive via FTP: cea-ftp.cea.berkeley.edu, pub/archive
----------------------------------------------------------------
The EUVE Project is managed by NASA's GSFC. The Project Manager
at GSFC is Mr. Paul Pashby, the Project Scientist is Dr. Yoji
Kondo, the Deputy Project Scientist is Dr. Ronald Oliversen. The
NASA Headquarters EUVE Program Scientist is Dr. Robert Stachnik
the Deputy Program Scientist is Dr. Derek Buzasi, the Program
Manager is Dr. Guenter Riegler. The Project Operations Director
is Mr. Kevin Hartnett. Information on the EUVE Guest Observer
Program is available from: Dr. Yoji Kondo, Mail Code 684 GSFC,
Greenbelt, MD 20771 (301)286-6247; euve@stars.SPAN.NASA.GOV
Article: 2620
Newsgroups: sci.space.news
From: Roger "F." Malina <rmalina@cea.Berkeley.EDU>
Subject: euve news for 11/14/92
Sender: usenet@news.arc.nasa.gov
Organization: Center for EUV Astrophysics, University of California at Berkeley
Date: Wed, 9 Dec 1992 06:01:32 GMT
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
------------------------------------------------------------------
Vol 2, No. 9 11/14/92 ISSN 1065-3597
------------------------------------------------------------------
EUVE discovers brightest EUV source in the sky
----------------------------------------------
Dr John Vallerga has reported to the EUVE science team that the B
star, epsilon Canis Majoris, is the brightest EUV source in the sky.
It was detected in the tin bandpass (centered at 600A) at
approximately 100 cps, and was also detected in the "Dagwood" filter
centered at 400A. The source is in the direction of the ISM tunnel
previously reported by Berkeley scientists. Because of the brightness
of the flux at long wavelengths, epsilon CMa has been added to the
EUVE calibration program.
ECLIPSING CATACLYSMIC VARIABLE OBSERVED BY EUVE
-----------------------------------------------
Dr Vallerga announced to the EUVE science team that EUVE has detected
and monitored the eclipsing cataclysmic variable UZ For. This CV was
originally discovered by EXOSAT and not detected by ROSAT WFC.
EUVE ARCHIVE ADDITIONS AND UPDATES
----------------------------------
ADDITIONS TO EUVE BIBLIOGRAPHY
Several additions to the EUVE Bibliography have been made in the last
month. The complete bibliography of EUVE papers from the Center for
EUV Astrophysics is available from the Public Archive via ftp. The
file EUVE_bib is a listing, in troff format, of all the EUVE papers,
categorized by subject.
To request one or more papers, e-mail editorial@cea.berkeley.edu,
giving your postal address and the number(s) of the paper(s) you want
from the list.
NEW SPECTRA RELEASED AU MIC flare, MCT 2020-4234
------------------------------------------------
The M0Ve star and calibration target AU Mic was seen to flare during
the In Orbit Calibration (IOC) observation which was carried out in
the early phase of the mission. The Public Archive has released two
more 1x spectra of AU Mic from the EUVE Short Wavelength (SW)
spectrometer, one representative of the flare ourburst, and one
representative of quiescence. Since no GO proposals were received by
NASA for this target, this data will not be released (for budgetary
reasons) for scientific analysis until the second round of the EUV
Guest Observer Program. Scientists interested in the scientific
analysis of this data should contact Dr Yoji Kondo, the EUVE Project
scientist.
The SW spectrum of the DA white dwarf MCT2020-4234 has also been
recently released. This calibration target was observed for boresight
and flux-throughput purposes.
If you have not used the EUVE public archive, you may obtain help by
sending e-mail to archive@cea.berkeley.edu with a message containing
the word "help" (omit quotes) on the first line with no preceding spaces.
A file containing information will be returned to you automatically.
Jeremy Drake
EUVE Archive Scientist
Results from the "Taste test" comparing detection algorithms.
-------------------------------------------------------------
Review of the source detection algorithms tested over the last several
weeks left many questions unanswered. Although no method was clearly
superior for detecting scanner sources, an approach was adopted for pro-
cessing the data and gradually improving the algorithm selected. Re-Proce-
ssing of the first 22 days of survey data should be completed by early
next week. For the Deep Survey Spectrometer (DS/S), none of the algo-
rithms resulted in a satisfactory method for detecting sources. Work on
the DS/S detection algorithms has been suspended in favor of improving
the scanner algorithms. As a result the collation of EUVE bright
source lists will be delayed.
------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Ex-
treme Ultraviolet Astrophysics, University of California, Berke-
ley. The opinions expressed are those of the authors. Publish-
ers: Roger F. Malina, C. Stuart Bowyer.Funded by NASA Contracts
NAS5-30180 and NAS5-29298.
Send newsletter correspondence to: carlos@cea.berkeley.edu (Internet)
EUVE Public Archive via FTP: cea-ftp.cea.berkeley.edu, pub/archive
----------------------------------------------------------------
The EUVE Project is managed by NASA's GSFC. The Project Manager
at GSFC is Mr. Paul Pashby, the Project Scientist is Dr. Yoji
Kondo, the Deputy Project Scientist is Dr. Ronald Oliversen. The
NASA Headquarters EUVE Program Scientist is Dr. Robert Stachnik
the Deputy Program Scientist is Dr. Derek Buzasi, the Program
Manager is Dr. Guenter Riegler. The Project Operations Director
is Mr. Kevin Hartnett. Information on the EUVE Guest Observer
Program is available from: Dr. Yoji Kondo, Mail Code 684 GSFC,
Greenbelt, MD 20771 (301)286-6247; euve@stars.SPAN.NASA.GOV
|
| 770.20 | Update - December 24 | VERGA::KLAES | I, Robot | Thu Dec 31 1992 14:55 | 111 |
| Article: 2747
From: rmalina@cea.Berkeley.EDU (RogerF. Malina)
Newsgroups: sci.space.news
Subject: EUVE detects is 100th EUV source
Date: 28 Dec 92 11:13:05 GMT
Sender: usenet@news.arc.nasa.gov
Organization: Center for EUV Astrophysics, University of California at Berkeley
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
------------------------------------------------------------------
Vol 2, No. 13 12/24/92 ISSN 1065-3597
------------------------------------------------------------------
EUVE DETECTS 100th EUV SOURCE
-----------------------------
Dr Antonella Fruscione has released a new version of the
internal EUVE Bright Source List covering the first 31 days
of the sky survey. In addition to the 24 sources detected
in the IOC and calibration, there are 76 sources detected
by the automatic detection software and verified visually
as "definite" sources. The breakdown of the 76 sources is
as follows:
17 Late type stars
10 WD
3 CV
1 Pn
1 Misc. (star with no spectral type, probably a WD)
18 B stars.
44 sources with no optical counterpart as yet
( note the 3 AGN were detected by detailed
analysis not by the automatic detection software)
( over 100 other possible sources from the first 31
days are being analysed further)
The breakdown by filter for the 76 sources is:
2 stars (WD) were detected in all 4 filters
7 stars were detected in Lex/B and Al/C
41 stars were detected in Lex/B only
15 stars were detected in Al/C only
4 stars were detected in Dag only
7 stars were detected in Tin only
( Lexan is "100A", Al is "200 A", Dagwood is "400A", tin is "600 A".)
EUVE GO PROGRAM TO START ON SCHEDULE
-------------------------------------
THE EUVE GO Phase will begin on schedule Jan 32, 1993. The
baseline GO plan for the first year was submitted to GSFC
on Dec 18 for detailed TDRSS scheduling. NASA HQ has notified
successful proposers of approved GO programs. If you are
uncertain of the status of your GO proposal, contact
Dr Yoji Kondo ( address below). The GO Support Group at
CEA has sent questionnairs to all Category I approved GOs
for verification of their target information. We apologise
for the error in some GO target data intoduced here at CEA.
(It wont happen again). If approved GOs havent received their
questionnaire, please send email to egoinfo@cea.berkeley.edu
If you havent replied to your questionnaire yet, please
do so as soon as possible. NOTE: IT is NOT possible to
send approved GOs the raw data on the calibration data on
their approved targets at this time. The only calibration
data that has been released is available on the EUVE public
archive. NASA has established an equity principle that
all GOs must be treated equally in terms of access to
data and analysis software. It is NOT possible for
GO co-Is located on the EUVE project at UCB to obtain early
access to calibration data that is not availble to outside
PIs and Co-Is.....
COME TO THE EUVE PAPERS AT AAS
-----------------------------
The EUVE early results will be presented at an oral session
monday morning January 3 10 am (session 23 Cortex room) at
the AAS meeting in Phoeniz, AZ, USA. This will be followed
by a dedicated EUVE poster session on Wednesday Jan 6
(session 80, Pavilion room). All interested EUVE GOs
are invited to come meet the EUV GO Support staff and
to review the early EUVE sky survey results as they pertain
to their GO observations.
HAPPY HOLIDAYS AND THE BEST FOR 1993
------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Ex-
treme Ultraviolet Astrophysics, University of California, Berke-
ley. The opinions expressed are those of the authors. Publish-
ers: Roger F. Malina, C. Stuart Bowyer.Funded by NASA Contracts
NAS5-30180 and NAS5-29298.
Send newsletter correspondence to: carlos@cea.berkeley.edu (Internet)
EUVE Public Archive via FTP: cea-ftp.cea.berkeley.edu, pub/archive
----------------------------------------------------------------
The EUVE Project is managed by NASA's GSFC. The Project Manager
at GSFC is Mr. Paul Pashby, the Project Scientist is Dr. Yoji
Kondo, the Deputy Project Scientist is Dr. Ronald Oliversen. The
NASA Headquarters EUVE Program Scientist is Dr. Robert Stachnik
the Deputy Program Scientist is Dr. Derek Buzasi, the Program
Manager is Dr. Guenter Riegler. The Project Operations Director
is Mr. Kevin Hartnett. Information on the EUVE Guest Observer
Program is available from: Dr. Yoji Kondo, Mail Code 684 GSFC,
Greenbelt, MD 20771 (301)286-6247; euve@stars.SPAN.NASA.GOV
|
| 770.21 | Update - January 15 | VERGA::KLAES | I, Robot | Mon Jan 18 1993 19:16 | 340 |
| Article: 2877
Newsgroups: sci.space.news
From: Roger "F." Malina <rmalina@cea.Berkeley.EDU>
Subject: EUVE NEWS - START OF GO PHASE
Sender: usenet@news.arc.nasa.gov
Organization: Center for EUV Astrophysics, University of California, Berkeley
Date: Sat, 16 Jan 1993 21:38:37 GMT
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
------------------------------------------------------------------
Vol 3, No. 1 1/15/93 ISSN 1065-3597
------------------------------------------------------------------
EUVE COMPLETES ALL SKY SURVEY
++++++++++++++++++++++++++++
The 6 month all sky survey phase of EUVE has been completed
and post survey calibration on targets stars is currently
under way. The EUVE Guest Observer program is being initiated
next week with observations of the planet Mars. During the
first six months of the GO Phase the few gaps in the sky survey
will also be filled in.
The EUVE observatory continues to operate exceptionally well and the
prospects are excellent for the Guest Observer program. Due to the
exceptional performance of the spacecraft, the observing constraints
for the GO phase have been relaxed from those originally planned -
targets up to 50 degrees from the ecliptic will be observable ( as
compared to the original constraint of 30 degrees for this phase). All
the spectrometer channels are working well - recent tests have also
indicated that two of the 3 spectrometer channels can take
scientifically useful data during portions of the day time side of the
orbit, thus increasing the observing efficiency of the satellite.
The EUVE Science Team would like to take the occasion of the
successfull completion of the first scientific milestone of
the EUVE mission to thank the whole NASA and contractor team
that contributed to the flawless operation of the EUVE Observatory.
EUVE GUEST OBSERVER SUPPORT PROGRAM; SCHEDULE FOR SOFTWARE AND DATA RELEASE
********************************************************** *****************
The IRAF software packages for reduction of spectroscopy obtained during
the pointed phase of the EUVE mission have been released internally at
CEA for further testing of calibration observations. The release,
called EGOCS 1.3 has been tested independently by the EUVE SWAT team.
The current packages contain all the functions for basic processing of
EUVE spectrometer data. These functions include retrieval of telemetry
and restructuring raw science and engineering data into tables, nominal
aspect and wavelength correction and simple extraction of spectra into
counts vs. wavelength. Testing indicates that the software is
functionally correct, that is, photons are processed successfully
through the event pipeline.
Now that the software has been thoroughly exercised, the data from
calibration pointings is being processed to iteratively refine the
wavelength and aspect solutions for the spectrometer. As might be
expected for a new astronomical telescope and associated instrumentation,
new effects appear in orbit and these must be accounted for in the
processing. The parameters that describe instrument and telescope
characteristics are called ``reference data'' in our nomenclature. It
is this reference data that is being refined through a repetitive
processing and measurement cycle. It is anticipated that the reference
data will evolve over the lifetime of the satellite, so accurate
measurement of the in-orbit performance of the instruments serves as an
important baseline for future data analysis.
Each Guest Observer will obtain
Raw Data in tabular form (FITS or STScI Table format)
Nominally processed spectrum (1-d)
Relevant reference data
EGO Software packages
Documentation
The schedule for releasing software and data listed below contains no
contingency for new unforseen problems or delays. It is an ambitious
schedule, but we hope that by concentrating our efforts we can meet
these dates. As can be seen, at first, delivery of GO data
(non-calibration) will lag the observation time by about two months.
Our goal is to shorten this to one week. As spectrometer data is
packaged with the software, reference data and documentation, we will
be able to support visitors to the CEA who wish to do their data
analysis here; the presence of the Guest Observer at CEA during their
observations is not required , since no interactive observing activies
involving the GO are required. However all EUVE GOs are strongly
encouraged to visit the CEA the first time they obtain EUVE data in
order to receive assistance and training in EUVE data reduction and
analysis techniques. EUVE is a new observatory and there remain many
subtleties in the correct interpretation of the EUVE data.
SCHEDULE:
mid-February - public release of EGO SW for processing spectrometer data
1 March - Best effort reference data release
1-22 March - Reprocessing and packaging of calibration pointings
allocated to Guest Observers
22 March - Initiate processing and packaging of first GO
(non-calibration) data
15 April - User Guides Versions 1
15 May - Nominally reduced calibration data (1-d spectra)
delivered to EUVE archive
In the next EUVE ELECTRONIC NEWS we provide the list of
Guest Observer targets approved by NASA.
------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Ex-
treme Ultraviolet Astrophysics, University of California, Berke-
ley, Ca 94720, USA. The opinions expressed are those of the authors.
Publish ers: Roger F. Malina, C. Stuart Bowyer.Funded by NASA Contracts
NAS5-30180 and NAS5-29298.
Send newsletter correspondence to: carlos@cea.berkeley.edu (Internet)
EUVE Public Archive via FTP: cea-ftp.cea.berkeley.edu, pub/archive
The EUVE Project is managed by NASA's GSFC. The Project Manager
at GSFC is Mr. Paul Pashby, the Project Scientist is Dr. Yoji
Kondo, the Deputy Project Scientist is Dr. Ronald Oliversen. The
NASA Headquarters EUVE Program Scientist is Dr. Robert Stachnik
the Deputy Program Scientist is Dr. Derek Buzasi, the Program
Manager is Dr. Guenter Riegler. The Project Operations Director
is Mr. Kevin Hartnett. Information on the EUVE Guest Observer
Program is available from: Dr. Yoji Kondo, Mail Code 684 GSFC,
Greenbelt, MD 20771 (301)286-6247; euve@stars.SPAN.NASA.GOV
END______________________________________________________________END
Article: 2880
Newsgroups: sci.space.news
From: Roger "F." Malina <rmalina@cea.Berkeley.EDU>
Subject: EUVE GO TARGET LIST
Sender: usenet@news.arc.nasa.gov
Organization: Center for EUV Astrophysics, University of California, Berkeley
Date: Sun, 17 Jan 1993 09:27:39 GMT
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
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Vol 3, No.2 1/15/93 ISSN 1065-3597
------------------------------------------------------------------
EUVE GUEST OBSERVER APPROVED TARGETS: SCHEDULE FOR OBSERVATION
***************************************************************
The approved target list for spectrometer observations was received in
mid-December 1992. Through heroic efforts by Pat Jelinsky and Mary
Samuel, the first science plans were submitted to GSFC. Building the
EUVE schedule depends heavily on two basic sets of information; first,
accurate coordinates, and secondly satellite constraints. In the process
of transcribing coordinates and computing coordinate transformations, errors
were made, some serious. The EGO Center has relied heavily on the responses to
the questionaire sent to the approved GOs. Unfortunately any delay
in response compromises the schedule as targets easily can slip in and
out of the schedule due to changes in recorded position.
At this time, the first few weeks of the EUVE pointed observations have
been scheduled. However as late as January 8th, some spacecraft constraints
were changing which required re-baselining the schedules.
Therefore at this time, the EUVE schedule is a highly dynamic entity.
Assuming the questionnaire responses are all received and the spacecraft
constraints stabilize, the EUVE schedule will be issued as a sliding 3
month detailed schedule with a longer range coarse schedule. The goal
is to attempt to release the first detailed schedule by the end of
January or mid February and Guest Observers affected will be contacted
individually. After the release of the first few weeks of detailed
schedule, the first 6 month's schedule will be released where target
names and the month of observation will be listed.
Included in this article is a list of all approved targets, where
``type 1'' and ``type 2'' targets are listed separately. Targets
that are specifically useful for calibration are noted.
TYPE 1 Targets
NAME RA DEC
P/ENCKE 0.00000 0.00000
WD_0004+330 1.89000 33.29667
NGC_246 11.77500 -11.87806
HD_7672 19.15083 -2.50028
HD_15638 37.06208 -61.30444
FEIGE_24 38.77917 3.73694 calibration
ALGOL 47.04208 40.95556
EF_ERI 48.55333 -22.59440
EPSILON_ERI 53.23250 -9.45830
NGC_1360 53.31375 -25.86306
HR_1099 54.19583 0.58778 calibration
VW_HYI 62.29708 -71.29500
71_TAU 66.58458 15.61861
MCT_0455-2812 74.30537 -27.86944 calibration
RE_0503-285 75.98083 -27.09000
G191-B2A 76.37083 52.80278 with calibration
G191_B2B 76.37750 52.83139 calibration
RE_0515+324 78.84875 32.67889
AB_DOR 82.18678 -65.44872
WD_0549+158 88.11042 15.88000 calibration
BETA_CMA 95.67500 -17.95600 calibration
RE_0623-374 95.80208 -36.30861
GEMINGA 98.47542 17.77000
SIRIUS_B 101.28958 -16.71194 calibration
MARS_1_1 104.50000 26.88333
EPSILON_CMA 104.65833 -28.97210 calibration
PSR_0656+14 104.95000 14.23917
PROCYON 114.82540 5.22500 calibration
SIGMA_GEM 115.82667 28.88333 calibration
U_GEM 118.77221 22.00186
HD_66811 120.89708 -40.00356
IX_VEL 123.82917 -49.22139
VELA 129.72583 -43.15056
HD_82558 143.10583 -11.18472
AD_LEO 154.90208 19.87000
RE_1032+532 158.03458 53.48889
WD_1057+719 165.14208 71.63361
WD_1123+189 171.57958 18.65472 calibration
RE_1149+28 177.48208 28.75222
PG_1159-035 180.44167 -3.76083
WD_1234+482 189.18583 47.92472
JUPITER 189.77373 -2.47334
GD_153 194.25958 22.03194
WD_1254+223 194.26375 22.02444 calibration
HZ_43 199.09417 29.09389 calibration
ALPHA_VIR 201.30000 -10.83833
BETA_CEN 210.95417 -60.37250
NGC_5548 214.49820 25.13676
PROX_CEN 217.42893 -62.67900
ETA_CEN 218.87500 -42.15720
ALPHA_CEN 219.90083 -60.83528 calibration
MK_478 220.53167 35.43931
HD_131156 222.84458 19.10247
H1504+65 225.53375 66.20667 calibration
PG_1520+525 230.44583 52.36778
AG_DRA 240.42083 66.80250
SIGMA_CRB 243.66917 33.85833
WD_1620-391 245.89667 -39.22361 calibration
HD_149499_B 249.62873 -57.46961
HER_X-1 254.45875 35.34186
LAMBDA_SCO 262.65000 -37.10330
HD_165341 271.36000 2.51469
AM_HER 274.05542 49.86750
K1-16 275.46667 64.36444
WD_1845+019 281.91458 1.95917 calibration
ALTAIR 297.69500 8.86830
MCT_2020-4234 305.99775 -41.59286 calibration
CYG_1992 307.63500 52.63139
WD_2111+498 318.18283 50.10500
HR_8210 321.61042 19.38250
SS_CYG 325.67625 43.58556
PKS_2155-304 329.71750 -30.22333 calibration
RE_2214-491 333.54958 -48.67611
EV_LAC 341.71583 44.33861
WD_2309+105 347.48333 47.96556 calibration
GD_246 348.08958 10.78444
HD_220140 349.85792 79.00417
EQ_PEG 352.96858 19.93786
LAMBDA_AND 354.39083 46.45833
II_PEG 358.76625 28.63361 calibration
R_AQUARII 359.00000 -16.50000
MOON_1_1 1005.00000 99.00000
TYPE 2 Targets
HD_4128 10.89708 -17.98667
ALPHA_ERI 24.42875 -57.23667
UV_CET 24.80250 -17.95192
BL_HYI 25.25167 -67.89128
CC_ERI 38.59119 -43.79764
VY_ARI 42.18208 31.11528
HD_20630 49.84000 3.37028
V471_TAU 57.60292 17.24661
EI_ERI 62.41958 -7.89222
THETA_1_TAU 67.14208 15.96250
V833_TAU 69.19583 27.13444
LS_V+4621 70.83750 46.70167
HR_1608 74.96042 -10.26833
LAMBDA_ERIDANI 77.28625 -8.75420
HD_33802_B 78.07583 -11.86475
CAPELLA 79.17208 45.99806 calibration
GRB_050379 81.49787 -66.07543
CHI_ORI 88.59542 20.27611
YY_GEM 113.65921 31.87075
YZ_CMI 116.17360 3.55542
VV_PUP 123.77833 -19.05489
HD_82210 143.62000 69.83028
RE_1027+322 156.80000 32.39000
X_12325 158.66042 39.64111
MK_421 166.09917 38.20389
AN_UMA 166.10750 45.05417
XI_UMA 169.54542 31.52917
PG_1211+143 183.57304 14.05350
KAPPA_DRA 188.37042 69.78806
HS_1224+4811 188.93750 -47.92500
31_COM 192.92417 27.54056
RE_1309+08 197.34583 8.24472
GRB_170592 203.30750 -16.71234
MU_CEN 207.40375 -42.47361
V834_CENT 212.28083 -45.28778
MR_SERP 238.19708 18.94028
RE_1629+781 247.31042 78.07444
GD356 250.22667 53.68556
RE_1938-461 294.64833 -46.21589 calibration
GRB_250592 300.86951 -42.57300
QQ_VUL 301.41917 22.66833
RE_2156-543 329.08708 -54.63389
AR_LAC 332.17042 45.74194
GRB_250392 350.56732 13.05916
RE_2324-544 351.12500 -54.68667
HD_223816 358.26500 -70.38833
QUESTIONS ABOUT THE SCHEDULING AND TARGETS SHOULD BE ADDRESSED
DIRECTLY TO DR CAROL CHRISTIAN at THE EUVE GUEST OBSERVER SUPPORT
CENTER - at EGOINFO@CEA.BERKELEY.EDU.
QUESTIONS ABOUT DATA RIGHTS, NASA GRANTS AND OTHER PROGRAMMATIC ISSUES
SHOULD BE ADDRESSED DIRECTLY TO DR YOJI KONDO to EUVE@STARS.SPAN.NASA.EDU
------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme Ultraviolet
Astrophysics, University of California, Berkeley, Ca 94720, USA. The opinions
expressed are those of the authors. Publishers: Roger F. Malina, C. Stuart
Bowyer. Funded by NASA Contracts NAS5-30180 and NAS5-29298. Send newsletter
correspondence to: carlos@cea.berkeley.edu (Internet). EUVE Public Archive via
FTP: cea-ftp.cea.berkeley.edu, pub/archive. The EUVE Project is managed by
NASA's GSFC. The GSFC Project Manager : Paul Pashby, Project Scientist :
Dr Yoji Kondo, Deputy Project Scientist : Dr Ronald Oliversen. The NASA
Headquarters Program Scientist: Dr Robert Stachnik, Deputy Program Scientist:
Dr Derek Buzasi, Program Manager: Dr Guenter Riegler. GSFC Project Operations
Director: Mr Kevin Hartnett. Information on the EUVE Guest Observer Program is
available from: Dr Yoji Kondo, Mail Code 684, GSFC, Greenbelt, MD 20771
(301)286-6247; email to euve@stars.SPAN.NASA.GOV
|
| 770.22 | EUVE Newsletter -- 02/07/93 | PONIL::J_BUTLER | E pur, si muove... | Thu Feb 11 1993 13:16 | 126 |
| Article 3048 of sci.space.news:
Newsgroups: sci.space.news
Path: nntpd2.cxo.dec.com!nntpd.lkg.dec.com!news.crl.dec.com!deccrl!caen!zaphod.mps.ohio-state.edu!howland.reston.ans.net!usc!elroy.jpl.nasa.gov!ames!dont-send-mail-to-path-lines
From: Roger "F." Malina <rmalina@cea.Berkeley.EDU>
Subject: EUVE GO Program starts
Message-ID: <1993Feb11.000431.7263@news.arc.nasa.gov>
Apparently-To: sci-space-news@ames.arc.nasa.gov
Followup-To: sci.space
Originator: yee@atlas.arc.nasa.gov
Sender: usenet@news.arc.nasa.gov
Organization: Center for EUV Astrophysics, University of California, Berkeley
Date: Thu, 11 Feb 1993 00:04:31 GMT
Approved: sci-space-news@ames.arc.nasa.gov
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
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Vol 3, No. 3 2/07/93 ISSN 1065-3597
------------------------------------------------------------------
EUVE GUEST OBSERVER PROGRAM INITIATED
-------------------------------------
The EUVE Guest Observer Program has been successfully initiated and
is proceding smoothly. As of Feb 5 the following targets have been
observed for Guest Observers:
Mars
HD_33959C
HR_2047
PSR_0656+14
RE_1032+532
WD1254+223_1.00_315
WD1314+293_1.00_135
WD_1123+189_0.65_270
The following EUVE results were presented at recent EUVE
science team meetings:
FIRST EUVE IMAGE OF CYGNUS LOOP
-------------------------------
Dr Peter Vedder presented the first images of the Cygnus Loop
as observed by EUVE in the Lexan Filter. The images show
distinct emission in the areas of the loop visible in
ground based and X ray images. Dr Richard Lieu reported that
the Vela supernova remnant has also been detected in the
lexan filter.
7 EXTRAGALACTIC OBJECTS NOW DETECTED BY EUVE
--------------------------------------------
Dr Herman Marshall and Dr Antonella Fruscione reported
that a total of 7 extragalactic objects have now been
detected by EUVE. Additional possible extragalactic sources
are being analysed.
HR1099 LIGHT CURVE PRESENTED
----------------------------
Dr Jeremy Drake presented the EUV light curve for the RsCVn
system HR1099 as detected in the EUVE deep survey lexan
filter. The strong signal shows modulation at the
expected period.
EUVE BRIGHT SOURCE LIST AUGMENTED
---------------------------------
Dr Antonella Fruscione and Dr Bob Patterer announced that
another 50 bright sources have been added to the EUVE
Bright Source list, bringing the current total to 135.
Another ~200 are in final stages of verificationa and are
expected to be released shortly.
EUVE Archive Releases Lunar Spectra
----------------------------------
The first calibration spectra of the nearly full moon were observed
on December 10, 1992 in the short, medium, and long wavelength spectrometers
of EUVE. These spectra are being released to the public in
an extremely raw format. No corrections for background subtraction
wavelength calibrations, or instrumental effects have been applied.
The Archive has made available a list of approved GO
targets in the file gotargets.txt.
Finally, the Archive has issued updates to several on-line documents.
The file caltargets.tbl contains information on
EUVE calibration targets updated to February 1993. The EUVE_bibs
document contains bibliographies of several new EUVE publications.
The file Datarights.txt contains revised data rights information
for the all sky survey and EUVE spectrometer data.
Please read the revised help file in the Archive for detailed information
on data retrieval techniques.
If you have not used the EUVE public archive, you may obtain help by
sending e-mail to archive@cea.berkeley.edu with a message containing
the word "help" (omit quotes) on the first line of the main body of
the text (ie not in the subject field), with no preceding spaces. A
file containing information will be returned to you automatically.
Approved EUVE Guest Observers should work with the EUVE Guest
Observer Support group (egoinfo@cea.berkeley.edu) rather than through
the EUVE public archive for matters pertaining to their observations.
------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Ex-
treme Ultraviolet Astrophysics, University of California, Berke-
ley, Ca 94720, USA. The opinions expressed are those of the authors.
Publishers: Roger F. Malina, C. Stuart Bowyer.Funded by NASA Contracts
NAS5-30180 and NAS5-29298.
Send newsletter correspondence to: carlos@cea.berkeley.edu (Internet)
EUVE Public Archive via FTP: cea-ftp.cea.berkeley.edu, pub/archive
The EUVE Project is managed by NASA's GSFC. The Project Manager
at GSFC is Mr. Paul Pashby, the Project Scientist is Dr. Yoji
Kondo, the Deputy Project Scientist is Dr. Ronald Oliversen. The
NASA Headquarters EUVE Program Scientist is Dr. Robert Stachnik
the Deputy Program Scientist is Dr. Derek Buzasi, the Program
Manager is Dr. Guenter Riegler. The Project Operations Director
is Mr. Kevin Hartnett. Information on the EUVE Guest Observer
Program is available from: Dr. Yoji Kondo, Mail Code 684 GSFC,
Greenbelt, MD 20771 (301)286-6247; euve@stars.SPAN.NASA.GOV
END______________________________________________________________END
|
| 770.23 | EUVE Newsletter -- 05/05/93 | PONIL::J_BUTLER | E pur, si muove... | Wed May 05 1993 14:23 | 195 |
| Article 3685 of sci.space.news:
Newsgroups: sci.space.news
Path: nntpd2.cxo.dec.com!pa.dec.com!decwrl!ames!dont-send-mail-to-path-lines
From: Roger "F." Malina <rmalina@cea.Berkeley.EDU>
Subject: new EUVE news [05/05/93]
Message-ID: <1993May5.140213.17677@news.arc.nasa.gov>
Apparently-To: sci-space-news@ames.arc.nasa.gov
Followup-To: sci.space
Originator: yee@atlas.arc.nasa.gov
Sender: usenet@news.arc.nasa.gov
Organization: Center for EUV Astrophysics, University of California at Berkeley
Date: Wed, 5 May 1993 14:02:13 GMT
Approved: sci-space-news@ames.arc.nasa.gov
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
------------------------------------------------------------------
Vol 3, No. 5 May 5, 1993 ISSN 1065-3597
------------------------------------------------------------------
EUVE SPACECRAFT AND INSTRUMENTS CONTINUE TO OPERATE FLAWLESSLY
--------------------------------------------------------------
FIRST EUVE TARGET OF OPPORTUNITY OBSERVED
------------------------------------------
The EUVE observatory continues to operate flawlessly. GO targets
observed since the last newsletter include Jupiter, Delta Cen,
HD 131156, PG1159, MU Cen, Mk 478, NGC 5548 and Eta Cen. EUVE
also observed its first Target of Opportunity with a coordinated
observation of the moon during the last Shuttle Flight. Astronomers
interested in possible target of opportunity observations should
phone the EUVE ESOC at 1-510-643-7087. TOO approvals will
be coordinated with the project scientists Dr Yoji Kondo.
The first EUVE GOs to receive their EUVE data have visited
the EUVE GO Support Group at CEA.
EUVE BRIGHT SOURCE LIST VERSION 3 RELEASED INTERNALLY AT UCB
------------------------------------------------------------
B Stroozas and the EUVE data analysis support group have released
version 3 of the EUVE Bright Source list internally to the EUVE
project. Version 3 now contains 456 sources. Of these some 242
have possible optical counterparts identified; 110 of these are late type
stars, 80 are hot white dwarfs, 9 are cataclysmic variables,
4 A star systems, 5 BL Lac objects, 2 AGN, 3 B stars, 2 central
stars of planetary nebulae, 1 low mass x ray binary and 1 pulsar. 25
are of undetermined spectal type.
The Bright Source list is currently being scrubbed for public
release with the NASA EUVE NRA and on the EUVE public archive.
This release is currently expected to occur before the end of May.
The EUVE Bright source list will also be distributed at the EUVE booth
at the AAS meeting in Berkeley, California.
EUVE GO NRA EXPECTED TO BE RELEASED IN MAY
------------------------------------------
As planned NASA plans to release the EUVE NRA
for the second round of the EUVE GO program in May. Proposals
will be due to NASA in August.
EUVE SPECTROSCOPIC DATA TO BE RELEASED PUBLICALLY
-----------------------------------------------------
The EUVE project will soon release publically the EUVE
calibration spectra . These spectra will provide
potential EUVE GOs with reference spectra to assist them.
In addition the data on the target AU MIC will also be
released; there are no approved GOs for the AU MIC data, hence
it will be deposited in the EUVE public archive. Exact dates
for the release of data will be announced at least two weeks
before the data is made public. Exact dates for the NASA NRA
and the public release of calibration spectra will be given in the
next EUVE electronic news. Watch this space !
EUVE RESULTS TO BE PRESENTED AT AAS MEETING IN JUNE
--------------------------------------------------
Early results from EUVE will be presented at the AAS meeting in
June being held in Berkeley, California. Titles of some
of the papers are listed here. To contact the lead author of
any paper send email to
(author first initial)(author lastname) @cea.berkeley.edu
eg for Antonella Fruscione send email to afruscione@cea.berkeley.edu
EUVE Scanner Observations of Supernova Remnants, J. Edelstein, P.\|W. Vedder,
and M. Sirk.
The Optical Identification Program for the EUVE Sky Survey, C. Christian, M. Abbott, C.\|A. Christian, M. Abbott, T. Carone, J. Drake, J. Dupuis, D.
Finley, A. Fruscione, I. Hawkins, R.\|F. Malina, H.\|L. Marshall and
J. Vallerga.
The EUV Coronal Spectrum of chi Ori (HR 2047, G0 V), B. Haisch, J.
Drake, and J.\|H.\|M.\|M.\| Schmitt.
The Distribution of Neutral Hydrogen in the Local Interstellar Medium,
A. Fruscione, I.
Hawkins, P. Jelinsky, and A. Wiercigroch.
Calibration and Processing of EUVE Spectrometer Observations, M. Abbott,
C. Christian, J. Dupuis, D. Finley, P. Jelinsky, and B. Boyd, A. Brown, and
S. Cully.
Extreme Ultraviolet Spectroscopic Observations of the Interstellar
Medium in Emission with EUVE, P. Jelinsky, J.\|V. Vallerga, J.
Edelstein, and S. Bowyer.
An EUVE Spectrum of the Moon, G.\|R. Gladstone, J.\|S. McDonald,
W.\|T. Boyd, and S. Bowyer.
Preliminary Results from the Extreme Ultraviolet Deep Survey, J.\|V.
Vallerga, J. Drake, and B. Antia.
Observations of Neutron Stars with EUVE, H. Marshall and L.\|R.
Cominsky.
EUVE All-Sky Survey Observations of the Magnetic Cataclysmic
Variable UZ~Fornaacis,
J.\|K. Warren, J.\|V. Vallerga, C.\|W. Mauche, K. Mukai,
and O.\|H.\|W.\| Siegmund.
Spatial Distribution of Diffuse Background in the 50---190 Angstrom
Waveband as Observed by the Deep Survey Telescope Aboard EUVE, R.
Lieu, T.\|J. Sumner, S. Bowyer, and S.\|D. Sidher.
The EUVE Background Zoo: Observations of EUV Background Anomalies, M. Eckert, G.\|R. Gladstone, C. Smith, and B.\|A. Stroozas.
Rotational Modulation of the EUV Coronal Emission from HR1099, J. Drake,A. Brown, R.\|J. Patterer, P.\|W. Vedder, S. Bowyer, E.\|F. Guinan, and J.
McDonald.
EUVE Observations of AR Lac During Eclipse, R.\|J. Patterer, J.
Drake, P. Vedder, N. Craig, and S. Bowyer.
Observations of the Transient GRO J0422+32, A. Wiercigroch and H. Marshall.
EUV Emission from AGN and BL Lac Objects, T.\|E. Carone, H.\|L.
Marshall, A. Fruscione, and S. Bowyer.
Diffuse Background Measurement with EUVE's Deep Survey Telescope
First-Light Images, M. Lampton, R. Lieu, S. Bowyer, P. Jelinsky, and
J. Edelstein.
Exreme Ultraviolet Emission from Flare Stars Observed with EUVE,
P.\|W. Vedder, R.\|J. Patterer, J. Drake, S. Cully, A. Brown, and B.
Pettersen.
Far and Extreme UV Spectroscopy of Hot White Dwarf Strs: A
Laboratory for Element Diffusion, S. Vennes.
EUVE Deep Survey Observations of a Flare on AD Leo, S. Cully,
O.\|H.\|W. Siegmund, G.H. fisher, and C.\|M. Johns, S.\|L. Hawley,
S. Duestra, and T. Simon.
The Ionization State of Local Interstellar Medium as Determined by
Extreme UV Spectroscopy of Hot White Dwarf Stars, T. Rumph.
The Long Wavelength EUVE Spectrum of the Hot DA White Dwarf
G191-B2B, J. Dupuis, S. Vennes, S. Bowyer, A.\|K. Pradhan, and J.
Drake.
In-orbit Performance of NASA's Extreme Ultraviolet Explorer
Observatory, R.\|F. Malina.
Early Results from the Extreme Ultraviolet Explorer, S. Bowyer.
------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme Ultraviolet
Astrophysics, University of California, Berkeley, Ca 94720, USA. The opinions
expressed are those of the authors. Publishers: Roger F. Malina, C. Stuart
Bowyer. Funded by NASA Contracts NAS5-30180 and NAS5-29298. Send newsletter
correspondence to: ceanews@cea.berkeley.edu (Internet). EUVE Public Archive via
FTP: cea-ftp.cea.berkeley.edu, pub/archive. The EUVE Project is managed by
NASA's GSFC. The GSFC Project Manager : Paul Pashby, Project Scientist :
Dr Yoji Kondo, Deputy Project Scientist : Dr Ronald Oliversen. The NASA
Headquarters Program Scientist: Dr Robert Stachnik, Deputy Program Scientist:
Dr Derek Buzasi, Program Manager: Dr Guenter Riegler. GSFC Project Operations
Director: Mr Kevin Hartnett. Information on the EUVE Guest Observer Program is
available from: Dr Yoji Kondo, Mail Code 684, GSFC, Greenbelt, MD 20771
(301)286-6247; email to euve@stars.SPAN.NASA.GOV
END-----EUVE---------ELECTRONIC---------------NEWS-------------------END
|
| 770.24 | EUVE Newsletter -- 05/29/93 | CXDOCS::J_BUTLER | E pur, si muove... | Wed Jun 02 1993 21:10 | 127 |
| Article: 3850
Newsgroups: sci.space.news
From: EUVE Electronic Newsletter distribution <ceanews@cea.Berkeley.EDU>
Subject: EUVE Newsletter, Vol. 3, No. 6, 11 May 1993
Sender: usenet@news.arc.nasa.gov
Organization: Center for EUV Astrophysics, University of California at Berkeley
Date: Sat, 29 May 1993 17:58:58 GMT
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
------------------------------------------------------------------
Vol 3, No. 6 May 11, 1993 ISSN 1065-3597
------------------------------------------------------------------
PUBLIC RELEASE OF EUVE CALIBRATION DATA
From: Ron Oliversen, EUVE Deputy Project Scientist, NASA-GSFC
*******************************************************************
A release of calibration data taken during In-Orbit-Checkout and
the Survey phase of the mission will be available through the EUVE
public archive on June 14. This release will be 1-d spectra (counts
vs. wavelength) as processed with EGO software version (1.1.1). Some
calibration data were processed with more recent versions, and a
README file is included with each spectrum to indicate the appropriate
software version. Included in this release, but available earlier on
(1 June), are the 1-d spectra of AU Mic in a quiescent and flare phase.
Also, the raw data set of AT Mic and EGO reduction software version
(1.1.1) will be released on June 7. AT Mic data and EGO software will
be available on CD ROM at the AAS meeting or by accessing the files
through the CEA ftp site. These spectra are being released WITHOUT
restrictions on their use. However, caution is advised against
over-interpretation and questions about the data reduction should be
directed to (egoinfo@cea.berkeley.edu). Also, the updated tables of
significantly improved telescope effective areas as a function of
wavelength are available through the public archive.
(The calibration targets that will be released are:
WD 1845, WD 2309, Procyon, WD 1620, MCT 2020, PKS 2155, HR 1099
Feige 24, Capella, WD 0549, G191 B2B)
EUVE SCIENCE ARCHIVE RELEASES FIRST CD ROM AT JUNE AAS
From: Jeremy Drake
******************************************************
Less than one year after launch, the EUVE Science Archive is pleased
to announce the impending release of Volume 1 Number 1 in what will
be a series of CD ROMs containing EUVE mission data and software.
The release coincides with the June 1993 AAS meeting, to be held at
UC Berkeley. If you plan to attend the AAS meeting, you may obtain a
copy of the CD at the EUVE stands. Details of how to request a copy
to be sent by mail to AAS non-attendees will be announced in a future
Newsletter. Please do not request a copy at this time.
CD ROM CONTENTS
---------------
The CD ROM contents include selected data from the first 7 months of
operation of the Extreme Ultraviolet Explorer Satellite, software for
reduction and analysis of data obtained in the EUVE Guest Observer
(EGO) program, and miscellaneous pertinent data and software.
AT MIC COMPLETE DATA SET
------------------------
AT Mic was observed as a spectrometer calibration target in July 1992.
The complete AT Mic data set from this observation is being made
available on EUVE CD ROM Vol. 1 No. 1. This data represents a sample
of the nominal EUVE Guest Observer Center (EGOC) processing of an
observation, and is similar to what is provided to each EUVE Guest
Observer for their observations.
The data is presented as 1-D FITS files containing the extracted
spectra, 2-D wavelength corrected FITS images, various telemetry and
engineering tables, and QPOE files containing photon position and time
information in binary tar format. Data reduction software, a
reference data set, and documents relating to the guest observer
software are also provided.
This data set will also be release simultaneously through anonymous
ftp to the Science Archive site (cea-ftp.cea.berkeley.edu).
EUVE BRIGHT SOURCE LIST
----------------------
Version 2a of the EUVE Bright Source list is recored on the CD in
LaTeX, PostScript, and ASCII formats. This version forms a subset of
those sources to appear in the actual BSL to be published with the
NASA Research Announcement. It contains information on all verified
survey sources from both the long-exposure (``deep'') survey of the
ecliptic and the all-sky survey, together with possible optical
counterparts found from a search of existing astronomical catalogues.
OTHER CONTENTS
In addition to the above, the CD also contains a compilation of
miscellaneous mission-related documents, images of extended sources
detected in the all-sky survey, images of the EUVE skymaps in four
bandpasses, C software to calculate the interstellar medium
transmission at EUVE wavelengths, and the complete collection of
publicly released EUVE calibration spectra.
EUV ASTRONOMY FEATURED AT AAS - INVITATION TO CEA RECEPTION
***********************************************************
The session on EUV Astronomy at the American Astronomical
Society meeting is being held on Tuesday June 8 from
8:30 to 5:30 pm. Latest results from EUVE, ROSAT WFC,
HUT, Voyager and theoretical discussions will be
presented. The evening poster session from 6-8pm will
be held at the Center For EUV Astrophysics at Berkeley.
A reception with no host bar will be held Tuesday
evening at CEA during the poster session. Details in
AAS registration packets.
-----------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme
Ultraviolet Astrophysics, University of California, Berkeley, Ca 94720,
USA. The opinions expressed are those of the authors. Publishers:
R. Malina, C. Stuart Bowyer. Funded by NASA Contracts NAS5-30180 and
NAS5-29298. Send newsletter correspondence to: ceanews@cea.berkeley.edu
EUVE Public Archive via FTP: cea-ftp.cea.berkeley.edu, pub/archive.
EUVE is managed by NASA's GSFC. The GSFC Project Manager: Paul Pashby,
Project Scientist: Dr Yoji Kondo, Deputy Project Scientist: Dr Ronald
Oliversen. NASA HQ Program Scientist: Dr Robert Stachnik, Dep. Program
Scientist: Dr D Buzasi, Program Manager: Dr G Riegler. GSFC Project
Operations Director: Mr Kevin Hartnett. Information on the EUVE Guest
Observer Program is available from: Dr Y Kondo, Mail Code 684, GSFC,
Greenbelt, MD 20771 (301)286-6247; email to euve@stars.SPAN.NASA.GOV
END-----EUVE---------ELECTRONIC---------------NEWS-----------------END
|
| 770.25 | New Discoveries by EUVE | CXDOCS::J_BUTLER | E pur, si muove... | Thu Jun 10 1993 14:30 | 103 |
| Article 3928 of sci.space.news:
Newsgroups: sci.space.news
Path: nntpd2.cxo.dec.com!nntpd.lkg.dec.com!pa.dec.com!decwrl!ames!dont-send-mail-to-path-lines
From: yee@atlas.arc.nasa.gov (Peter Yee)
Subject: New discoveries by NASA's EUV Explorer presented [Release 93-105] (Forwarded)
Message-ID: <1993Jun7.211215.2515@news.arc.nasa.gov>
Apparently-To: sci-space-news@ames.arc.nasa.gov
Followup-To: sci.space
Originator: yee@atlas.arc.nasa.gov
Sender: usenet@news.arc.nasa.gov
Reply-To: yee@atlas.arc.nasa.gov (Peter Yee)
Organization: NASA Ames Research Center, Moffett Field, CA
Date: Mon, 7 Jun 1993 21:12:15 GMT
Approved: sci-space-news@ames.arc.nasa.gov
Lines: 85
Paula Cleggett-Haleim
Headquarters, Washington, D.C.
(Phone: 202/358-0883) 2:30 p.m. EDT, June 7, 1993
Randee Exler
Goddard Spaceflight Center, Greenbelt, Md.
(Phone: 301/286-0697)
RELEASE: 93-105
NEW DISCOVERIES BY NASA'S EUV EXPLORER PRESENTED
Recent discoveries from NASA's Extreme Ultraviolet Explorer (EUVE)
will be presented June 7 and 8, 1992, at the 182nd National Meeting of the
American Astronomical Society (AAS), University of California at Berkeley
following the 1-year anniversary of EUVE's launch.
The new results include discovery of elements that blanket the light
from white dwarf stars, the detection of ionized helium in the local
interstellar gas, the detection of an extreme ultraviolet shadow in the local
interstellar medium and new findings on the mysteries of rare extragalactic
objects.
The astronomers will discuss why hot white dwarf stars emit only small
amounts of extreme ultraviolet radiation, despite that their high temperatures
should make them produce large amounts of EUV radiation. EUVE data reveal
that unexpected elements - mostly iron - may work as a blanket which blocks
the EUV radiation and prevent it from escaping into space.
This information promises important new results about the evolution of
stars into the white-dwarf stage and may help astronomers calculate the details
of how stars age and die, as our the sun will die when it becomes a white dwarf
in about 5 billion years, according to the astronomers.
What physical conditions describe the gas surrounding this solar
system? The EUVE has allowed astronomers for the first time to observe ionized
helium (helium atoms that have lost one of their two electrons) in the gas that
floats among the sun and nearby stars. The EUVE satellite's observations may
soon yield far better measurements of the density, temperature and ionization
state of this interstellar gas than have been possible until now.
The Deep Survey Telescope on board EUVE has obtained the first direct
evidence that the gas and dust drifting among the stars in this galaxy emit a
faint glow in the EUV. EUVE observed an EUV "shadow" cast by this gas and
dust cloud. The cloud lies in the direction of the constellation Taurus and is
believed to be approximately 200 light-years away. Its location indicates to
astronomers that the hot, ionized gas of the local interstellar medium extends
much farther than previously thought.
Unraveling the Nature of Extragalactic Objects
The first sky survey ever conducted in the entire EUV band of the
electromagnetic spectrum has revealed that some of the rarest, most exotic
objects in the universe -- BL Lacertae Objects (BL Lacs) -- are surprisingly
visible in the EUV. The finding, which will be discussed at this meeting,
brings scientists one step closer to puzzling out the mysterious nature of BL
Lacs.
BL Lacs are comparatively rare and are theorized to be centered on
massive black holes. By analyzing the EUV light given off by these objects,
scientists may learn more about the composition and velocities of matter
entering possible black holes.
Active galactic nuclei (AGN) are another class of rare extragalactic
objects to be discussed at this meeting. Many of the AGNs seen in previous
surveys either were detected weakly or not observed at all in the EUV. EUVE
has revealed that some AGNs are visible in the EUV because their central source
of energy is powerful enough to clear a path through the surrounding, otherwise
opaque neutral gas.
The EUVE was launched June 7, 1992 to make the first survey of the
universe at all the wavelengths contained in the EUV band of the spectrum.
The Center for Extreme Ultraviolet Astrophysics (CEA), under contract to
NASA's Goddard Space Flight Center, Greenbelt, Md., serves as the Science
Operations and Data Analysis Facility for EUVE. EUVE is part of NASA's Office
of Space Science's Explorer program in Washington, D.C.
- end -
EDITORS NOTE: Guest observers and astronomers from the CEA in Berkely will
present the new results during a press conference on June 7 at 2:30 a.m. EDT.
The AAS press room, located in the West Madrone Room, Student Union,
University of California at Berkeley, opens 1 p.m., June 6. Media needing
assistance may call (510) 643-7070, -7120 or -7137.
|
| 770.26 | EUVE Newsletter -- 06/03/93 | CXDOCS::J_BUTLER | E pur, si muove... | Thu Jun 10 1993 14:33 | 232 |
| Article 3933 of sci.space.news:
Newsgroups: sci.space.news
Path: nntpd2.cxo.dec.com!pa.dec.com!decwrl!wupost!tulane!ames!dont-send-mail-to-path-lines
From: EUVE Electronic Newsletter distribution <ceanews@cea.Berkeley.EDU>
Subject: EUVE Electronic Newsletter [06/03/93]
Message-ID: <1993Jun8.104406.23555@news.arc.nasa.gov>
Apparently-To: sci-space-news@ames.arc.nasa.gov
Followup-To: sci.space
Originator: yee@atlas.arc.nasa.gov
Sender: usenet@news.arc.nasa.gov
Organization: Center for EUV Astrophysics, University of California at Berkeley
Date: Tue, 8 Jun 1993 10:44:06 GMT
Approved: sci-space-news@ames.arc.nasa.gov
Lines: 215
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
------------------------------------------------------------------
Vol 3, No. 7 June 3, 1993 ISSN 1065-3597
------------------------------------------------------------------
NEW RELEASES FROM THE EUVE SCIENCE ARCHIVE AND EGO CENTER
---------------------------------------------------------
In a busy month, the EUVE CD-ROM Vol.1 No.1, a new version of EUV/IRAF
package, revised GO reference data, and the EGO Center Users' Guide
are all being made available through the EUVE Science Archive.
The wavelength-calibrated AU Mic calibration data were released on
June 1st, as announced in the last Electronic Newsletter. Further
calibration data will be release on the 14th June - see the announcement
at the end of this Newsletter
EUVE AT AAS MEETING - INVITATION TO CEA RECEPTION
-------------------------------------------------
EUVE will host a booth at the AAS meeting at UC Berkeley, starting on
the 6th June - come by and see us. EUVE staff will be on-hand to
discuss aspects of the mission, demonstrate some software and
generally point you in the right direction if you are seeking
EUVE-related information.
The session on EUV Astronomy at the American Astronomical Society
meeting is being held on Tuesday June 8 from 8:30 to 5:30 pm. Latest
results from EUVE, ROSAT WFC, HUT, Voyager and theoretical discussions
will be presented. The evening poster session from 6-8pm will be held
at the Center For EUV Astrophysics at Berkeley. A reception with no
host bar will be held Tuesday evening at CEA during the poster
session. Details in AAS registration packets.
CD-ROM RELEASED AT AAS MEETING
-----------------------------
The EUVE Science Archive is pleased to announce the release of the
EUVE CD-ROM Vol.1 No.1 "Selected Data and Software", to coincide with
the 182nd Meeting of the American Astronomical Society, to be held at
UC Berkeley, next week. Attendees of the meeting may pick up
a copy at the EUVE display booth. If you are not planning to
attend the meeting, you may order the CDROM either by conventional
mail or by e-mail. The CD-ROM contains data and software from the
first 7 months of operation of EUVE, including the entire AT Mic
data set.
AT Mic was observed as a spectrometer calibration target in July 1992.
This data represents a sample of the nominal EUVE Guest Observer
Center (EGOC) processing of an observation, and is similar to what is
provided to each EUVE Guest Observer for their observations. The data
is presented as 1-D FITS files containing the extracted spectra, 2-D
wavelength corrected FITS images, various telemetry and engineering
tables, and QPOE files containing photon position and time information
in binary tar format. Data reduction software, a reference data set,
and documents relating to the guest observer software are also
provided.
ORDERING THE CD-ROM BY E-MAIL
-----------------------------
The archive has created an automatic CD-ROM ordering facility whereby
the scientific community may request the EUVE CD-ROM through e-mail.
The CD will sent by US Mail and should arrive within two weeks
for domestic orders, and within one month for international orders.
To order a CD by e-mail, send an e-mail message to
archive@cea.Berkeley.Edu
containing the word "mailorder" (NOT in the subject field) followed by
a space and the item name (in this case "cdrom1.1", with quotes
omitted). Please do not include any other archive requests or
messages prior to your order, or your order will not be interpreted
correctly by the mailserver software. Following your order, on a new
line, include the mailing information sufficient to allow us to send
you order by US Mail, and a contact phone number.
Example:
--------
The following message sent to archive@cea.Berkeley.Edu will be
interpreted as an order by Socks Clinton at the White House for the
EUVE CD-ROM Vol.1 No.1:
mailorder cdrom1.1
Socks Clinton
1600 Pennsylvania Ave, NW
Washington, DC 20500
(202) 456-1111
Socks would receive the CD by US Mail in about two weeks.
ORDERING THE CD BY US MAIL
--------------------------
Simply send a letter to
The EUVE Science Archive
Center for EUV Astrophysics
University of California
2150 Kittredge St
Berkeley CA 94720
containing your request and return mailing address, e-mail address and
telephone number.
NEW RELEASES FROM EUVE GO CENTER
--------------------------------
This article announces the release of several products of interest to
EUVE Guest Observers and other using the EUV/IRAF software package. All
of these products are available through the EGO Center ftp site at
cea-ftp.cea.Berkeley.Edu. When obtaining these products, be certain to
get the highest numbered version available at the time.
EUV/IRAF Package
----------------
Version 1.2.1 of the EUV software package contains substantial changes
from earlier versions. These changes are primarily in the user interface:
many parameters have been renamed or reorganized, tasks in the package
have been made more consistent with one another in their use of some
parameters, and help pages have been cleaned up. Because of the nature of
these changes, after installation of the new version of the package, users
will want to "unlearn" any tasks for which they have saved parameter sets
in order to pick up the changes.
Software versions beginning with 1.2 also contain a major improvement in
the pipeline processing task "cep" to correct for false spectral features
due to binning effects. If you are working with EUVE spectral data which
was processed using a version of the software earlier than 1.2 it is
strongly recommended that you obtain the most current version and rerun
the pipeline on your data. The problem will be especially noticeable for
bright, low-noise spectra. The process of re-running the pipeline is
described in the EGO User's Guide, as is a lengthy description of the
binning effect.
EGODATA Reference Data
----------------------
The new software version requires a new version of the EGODATA reference
data set. The current release is version 1.6. Guest Observers with any
version prior to 1.6 will want to get the most current version to correct
an error in the "detector.tab" file which rendered several software tasks
unusable.
EGO Center User's Guide
-----------------------
The initial draft (version 0.1) of the EGO Center User's Guide is now
available in Postscript format. This document contains descriptions of
the data products delivered to Guest Observers, discusses major known
instrumental effects, describes important tasks in the EUV software, and
gives examples of common processing steps.
PUBLIC RELEASE OF EUVE CALIBRATION DATA
---------------------------------------
From: Ron Oliversen, EUVE Deputy Project Scientist, NASA-GSFC
*******************************************************************
A release of calibration data taken during In-Orbit-Checkout and the
Survey phase of the mission will be available through the EUVE public
archive on June 14. This release will be 1-d spectra (counts vs.
wavelength) as processed with EGO software version (1.1.1). Some
calibration data were processed with more recent versions, and a
README file is included with each spectrum to indicate the appropriate
software version. The calibration targets that will be released are:
WD 1845, WD 2309, Procyon, WD 1620, MCT 2020, PKS 2155, HR 1099 Feige
24, Capella, WD 0549, G191 B2B. Also now available (on 1 June), are
the 1-d spectra of AU Mic.
The raw data set of AT Mic and EGO reduction software version (1.1.1)
will be released on the EUVE CD-ROM Vol.1 No.1 at the AAS Meeting next
week - see the notice above for details.
These spectra are being released WITHOUT restrictions on their use.
However, caution is advised against over-interpretation and questions
about the data reduction should be directed to
egoinfo@cea.Berkeley.Edu.
-----------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme
Ultraviolet Astrophysics, University of California, Berkeley, CIA 94720,
USA. The opinions expressed are those of the authors. Publishers:
R. Malina, C. Stuart Bowyer. Funded by NASA Contracts NAS5-30180 and
NAS5-29298. Send newsletter correspondence to: ceanews@cea.Berkeley.Edu
EUVE Public Archive via FTP: cea-ftp.cea.Berkeley.Edu, pub/archive.
EUVE is managed by NASA's GSFC. The GSFC Project Manager: Paul Pashby,
Project Scientist: Dr Yoji Kondo, Deputy Project Scientist: Dr Ronald
Oliversen. NASA HQ Program Scientist: Dr Robert Stachnik, Dep. Program
Scientist: Dr D Buzasi, Program Manager: Dr G Riegler. GSFC Project
Operations Director: Mr Kevin Hartnett. Information on the EUVE Guest
Observer Program is available from: Dr Y Kondo, Mail Code 684, GSFC,
Greenbelt, MD 20771 (301)286-6247; email to euve@stars.SPAN.NASA.GOV
END-----EUVE---------ELECTRONIC---------------NEWS-----------------END
|
| 770.27 | EUVE Newsletter -- 06/18/93 | CXDOCS::J_BUTLER | E pur, si muove... | Thu Jul 01 1993 21:06 | 114 |
|
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
------------------------------------------------------------------
Vol 3, No. 8 June 18, 1993 ISSN 1065-3597
------------------------------------------------------------------
PUBLIC RELEASE OF EUVE CALIBRATION DATA
---------------------------------------
In accordance with the announcements made in earlier Newsletters, the
EUVE Science Archive is pleased to release the wavelength calibrated
spectra of the calibration targets WD 1845, WD 2309, Procyon, WD 1620,
MCT 2020, PKS 2155, HR 1099 Feige 24, Capella, WD 0549, and G191 B2B.
This release is in 1-d spectra (counts vs. wavelength) format, as
processed with EGO software version (1.1.1). Also available, from a
previous release, are the 1-d spectra of AU Mic.
These spectra were produced using the nominal reduction procedures
performed at the EGO Center on all Guest Observer observations and
should not be considered optimal reductions. Several problems may be
present, including detector features such as hotspots; false spectral
features introduced by binning effects during the reduction or detector
distortions; errors in the wavelength solution; loss of counts due to
instrument deadtime or Primbsching; and incorrect spectral extraction
and background subtraction. These problems are discussed at length in
the EGO Center User's Guide which is also available through this ftp
site.
In addition, the spectra are being released WITHOUT restrictions on
their use. However, caution is advised against over-interpretation and
questions about the data reduction should be directed to
egoinfo@cea.Berkeley.Edu.
ORDERING THE EUVE CD-ROM
------------------------
The first EUVE CD-ROM is still available to the scientific community on
request. CDs may be ordered by contacting the Archive via US Mail or by
utilizing the electronic mail CD-ROM ordering facility. To order by
e-mail, send a message to
archive@cea.berkeley.edu
containing the command line "mailorder cdrom1.1" (omit quotes) in the
main body of the text (ie not in the subject field), followed by
your mailing address and contact telephone number.
eg:-
mailorder cdrom1.1
Dr. Frederick Bloggs
Department of Bloggonomy
Bloggs University
Bloggstown, BL 99999
Tel. (999) 999-9999
The CD will sent by US Mail and should arrive within two weeks for
domestic orders, and within one month for international orders. For
more details on using the mailserver program please refer to the
archive help file, which may be obtained from the archive ftp site and
the archive mailserver. To obtain the help file from the mailserver
send an e-mail message to archive at the above address containing the
word "help" (again, not in the subject field and omitting quotes). To
obtain the help file from the ftp site, ftp to
cea-ftp.cea.berkeley.edu. The help file is located in the pub/archive
directory.
ARCHIVE UPDATES
----------------
Many of the data files located in the FTP and mailserver sites
of the archive have been renamed or updated. Please refer to the new
archive index file for the latest file names and any new additions.
NEW EGO RELEASE
---------------
The EUVE Guest Observer Center would like to announce the release of
version 1.7 of the EGODATA reference data set. The change of most concern
to Guest Observers or potential proposers for the second year of GO
observations is an update to the set of effective areas for the spectrometers.
The release is available as a compressed tar file through the ftp site at
cea-ftp.cea.berkeley.edu, in the"pub/reference/egodata1.7/" directory.
See the README and INSTALL filesin that directory for instructions.
-----------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme
Ultraviolet Astrophysics, University of California, Berkeley, CIA 94720,
USA. The opinions expressed are those of the authors. Publishers:
R. Malina, C. Stuart Bowyer. Funded by NASA Contracts NAS5-30180 and
NAS5-29298. Send newsletter correspondence to: ceanews@cea.Berkeley.Edu
EUVE Public Archive via FTP: cea-ftp.cea.Berkeley.Edu, pub/archive.
EUVE is managed by NASA's GSFC. The GSFC Project Manager: Paul Pashby,
Project Scientist: Dr Yoji Kondo, Deputy Project Scientist: Dr Ronald
Oliversen. NASA HQ Program Scientist: Dr Robert Stachnik, Dep. Program
Scientist: Dr D Buzasi, Program Manager: Dr G Riegler. GSFC Project
Operations Director: Mr Kevin Hartnett. Information on the EUVE Guest
Observer Program is available from: Dr Y Kondo, Mail Code 684, GSFC,
Greenbelt, MD 20771 (301)286-6247; email to euve@stars.SPAN.NASA.GOV
END-----EUVE---------ELECTRONIC---------------NEWS-----------------END
|
| 770.28 | EUVE Newsletter -- 07/21/93 | CXDOCS::J_BUTLER | E pur, si muove... | Mon Jul 26 1993 14:28 | 200 |
|
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
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Vol 3, No. 10 July 21, 1993 ISSN 1065-3597
------------------------------------------------------------------
NEW ARCHIVE RELEASES
--------------------
**********
ISM SERVER
**********
The EUVE Science Archive is announcing a new service which allows users
to calculate interstellar medium transmission remotely, via electronic
mail. The ISM server, installed under the "archive" e-mail address,
can feed the input variables sent within an e-mail message to the ISM
executable located in the archive. The server then will automatically
return output values to the sender in an electronic mail message. The
ISM model employed is that of Rumph, T., Bowyer, S., and Vennes, S.,
1993, ApJ submitted (available from the Center for EUV Astrophysics in
preprint form by request to editorial@cea.berkeley.edu or the lead
author; toddr@cea.berkeley.edu)
The mailserver uses the same C routines as those which reside in the
archive ism directory, and which are available for copying through
the mailserver or by anonymous FTP.
To use the ISM server send email to archive@cea.berkeley.edu.
The first line of the text of the message should be in the following
format: the word "ism" (omit quotes) followed by the hydrogen column
density (in units number/cm**2), a space, the neutral helium to neutral
hydrogen number density ratio (HeI/HI), a space, the once ionized He to
neutral hydrogen number density ratio (HeII/He) and a carriage return.
The succeeding lines should contain x,y pairs corresponding to
wavelength in Angstroms, and unattenuated flux, separated by a spaces.
The output file, returned to the user via email, will have two columns,
wavelength and the flux*ism_transmission.
For example, the following message will be interpreted by the
mailserver program as a request for an ISM calculation, using a H
column of 1.0e18, with HeI/HI=0.1 and HeII/HI=0.01, for the wavelengths
and fluxes on the lines following the "ism" keyword :-
**************
User commands
**************
mail archive
Subject: test
ism 1.e18 0.1 0.01
100 1.0
200 1.0
300 1.0
**************
archive output
**************
>From archive Wed Jul 14 12:20:34 1993
Return-Path: <archive>
Received: from sdaf1 by sdaf1 (4.1/SMI-3.2)
id AA10441; Wed, 14 Jul 93 12:20:33 PDT
Date: Wed, 14 Jul 93 12:20:33 PDT
From: EUVE Archive <archive>
Message-Id: <9307141920.AA10441@sdaf1>
Subject: Reply from archive re: ISM
Apparently-To: testuser
100.000000 0.962993
200.000000 0.804165
300.000000 0.567427
Note that the fluxes can be in any units. (Submitting 1.0 as the flux
for a given wavelength yields, of course, the transmission factor,
which, when multiplied by a flux in arbitrary units yields the
ISM-attenuated flux.)
This facility is a prototype of a service which is planned for future
implementation, whereby the user can submit input data for a variety
of on-line programs using electronic mail.
WARNING
-------
The ism routine should not be treated as a black box. While
it has been extensively tested, The EUVE Archive does not hold
responsibility for any errors or for any consequences of errors
which might remain.
NEW EGO RELEASES
----------------
***********************************
Announcement of AU Mic data release
***********************************
The entire AU Mic data set including flare episode obtained last July
2-4, 1992 will be released on August 2, 1993. The data will be
distributed on 8mm tape in the standard EUVE Guest Observer format
including nominally reduced 1-d spectra, all raw data (photon events
and engineering telemetry), reference data, analysis software, and
QPOE files. The data is NOT proprietary and may be used for analysis
and publication once the data is released. The data may be ordered
by sending a request to (Internet) "egoinfo@cea.berkeley.edu".
Technical questions regarding the analysis software should likewise be
directed to "egoinfo@cea.berkeley.edu" or phone (510)-643-5056.
Support will be provided on a best effort basis. The data from the
upcoming AU Mic observation scheduled for July 22, 1993 will be
released at a later date.
******************************
EUVE Cycle II NRA Availability
******************************
The EUVE Cycle II NRA is available to prospective Guest Observers in
paper and electronic formats. Requests for hardcopies of the NRA
should be sent to:
NSInet: STARS::EUVE
Internet: euve@stars.gsfc.nasa.gov
Phone: (301) 286-7664
Fax: (301) 286-7642
Requests are usually mailed out within 24 hours and copies are FedEx
to foreign countries.
Electronic copies for the NRA are available via anonymous ftp (File
Transfer Protocol), as follows:
% ftp 128.32.154.12
Enter your login name for your password.
Password:
Change to the NRA directory
ftp> cd pub/nra
Each subdirectory contains files relating to the NRA. Both text and
postscript versions are available. For each file that you want, type:
ftp> get <filename>
If you have any questions or problems using the anonymous ftp please
contact the EUVE Guest Observer Center at:
Internet: egoinfo@cea.berkeley.edu
Phone: (510) 643-5056
Or, you may contact Dr. Yoji Kondo (Project Scientist) at (301) 286-6247
or Dr. Ron Oliversen (Deputy Project Scientist) at (301) 286-6290.
The EUVE proposals must be received by September 3, 1993 and should be sent to:
Dr. Yoji Kondo
NASA/Goddard Space Flight Center
Code 684
Building 21, Room G59
Greenbelt, MD 20771.
An electronic submission of the target list (see the NRA for details)
is also required and should be send to:
egoinfo@cea.Berkeley.EDU
The deadline is also September 3, 1993.
-----------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme
Ultraviolet Astrophysics, University of California, Berkeley, CIA 94720,
USA. The opinions expressed are those of the authors. Publishers:
R. Malina, C. Stuart Bowyer. Funded by NASA Contracts NAS5-30180 and
NAS5-29298. Send newsletter correspondence to: ceanews@cea.Berkeley.Edu
EUVE Public Archive via FTP: cea-ftp.cea.Berkeley.Edu, pub/archive.
EUVE is managed by NASA's GSFC. The GSFC Project Manager: Paul Pashby,
Project Scientist: Dr Yoji Kondo, Deputy Project Scientist: Dr Ronald
Oliversen. NASA HQ Program Scientist: Dr Robert Stachnik, Dep. Program
Scientist: Dr D Buzasi, Program Manager: Dr G Riegler. GSFC Project
Operations Director: Mr Kevin Hartnett. Information on the EUVE Guest
Observer Program is available from: Dr Y Kondo, Mail Code 684, GSFC,
Greenbelt, MD 20771 (301)286-6247; email to euve@stars.SPAN.NASA.GOV
END-----EUVE---------ELECTRONIC---------------NEWS-----------------END
|
| 770.29 | EUVE Newsletter - November 5 | VERGA::KLAES | Quo vadimus? | Sun Nov 07 1993 12:57 | 281 |
| From: US1RMC::"ceanews@cea.Berkeley.EDU" "EUVE Electronic Newsletter
distribution" 5-NOV-1993 21:00:42.16
To: euvenews@imperial.berkeley.edu
CC:
Subj: EUVE Electronic Newsletter
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
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Vol 3, No. 15 November 5, 1993 ISSN 1065-3597
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1. Notes from the Editor
========================
by Brett A. Stroozas (DASS/Archive Manager)
Welcome to this issue of the Extreme Ultraviolet Explorer (EUVE) electronic
newsletter. Included in this issue are an announcement from the EUVE User's
Committee, some announcements regarding the EUVE Guest Observer (EGO) Program
and the second EUVE NASA Research Announcement (NRA), some abstracts from up-
coming publications of EUVE-related papers, and some brief articles from EGO
Center staff regarding the performance of the Deep Survey/Spectrometer instru-
ment.
Highlighting some of the science coming out of the Center for EUV Astrophy-
sics (CEA) here at U.C. Berkeley, is the upcoming publication in the Astro-
nomical Journal of the EUVE survey Bright Source List paper (356 sources;
see abstract below). The first EUVE survey catalog has also recently been
completed (410 sources) and a paper (Bowyer, et al.) has been submitted to
the Astrophysical Journal Supplement. Additionally, the EUVE Science Archive
group is preparing to release the next installment in the EUVE CD-ROM series
at the January meeting of the American Astronomical Society in Washington, D.C.
This release will be a set of three CD-ROMs containing pointed spectrometer
observations of selected calibration targets from the In-Orbit Calibration
(IOC) and survey phases of the mission. These eleven observations have been
arranged thematically on the three disks: four white dwarfs on disc A; two
late-type stars on disc B; and five assorted targets on disc C.
2. EUVE User's Committee Lunch at AAS Meeting
=============================================
A special luncheon meeting is being held by the EUVE User's Committee at
the American Astronomical Society Conference on Thursday, 13 January 1994
for everyone interested in extreme ultraviolet astronomy. Planned topics of
discussion are a current update on EUVE and the ongoing efforts to extend the
EUVE mission. If the mission is not extended, EUVE observations will end af-
ter a third year of GO observations (according to the current plan). Members
of the user community are encouraged to attend as increased participation in
this meeting will enhance the possibility of additional opportunities to do
research utilizing data from EUVE. Harry Shipman is the meeting organizer
and will announce further information in the near future. We hope to see you
all there.
3. Extreme Ultraviolet Explorer Second NRA
==========================================
by Dr. Ronald Oliversen (Deputy Project Scientist at GSFC)
This September, a total of 109 proposals, including 26 proposals from for-
eign countries, were received in response to the second EUVE NRA for the Guest
Observer program. The proposals were submitted by 79 Principal Investigators
(PI's) from 45 different institutions. Thirty of the PI's had not previously
proposed to the EUVE GO program. The 109 proposals covered a wide range of
topics from the solar system (6), interstellar medium (7), subluminous stars
(16), binary systems (30), cool stars (28), hot stars (6), unidentified sour-
ces (3), to extragalactic objects (13). The number of targets per proposal
is 2.5 with an oversubscription for time requested of about 3. The peer review
of proposals will occur November 8 and 9.
4. EGO Program Announcements
============================
by Anne Miller (EGO Technical Writer)
As mentioned above, a total of 109 proposals were received from 79 PI's for
Cycle II of the EUVE Guest Observer Program. Technical evaluations by EGO
Center scientists are underway, and the NASA Peer Review is currently sched-
uled for 8 and 9 November. The Review will be conducted jointly with the 1994
IUE Peer Review.
The EGO Center wishes to apologize for a lapse in the announcements of
planned observations to PI's. The practice has been resumed, and Cycle I PI's
should receive an electronic notice that their observation has been scheduled
up to one month before the scheduled date. Any GO who is organizing coordi-
nated observations or has other scheduling concerns is urged to contact the
EGO Center via e-mail at "egoinfo@cea.berkeley.edu" (Internet) whenever in
need of assistance. Scheduling questions and problems are always addressed
as promptly as possible.
5. Abstracts of Upcoming Publications of EUVE-related Papers
============================================================
The following four abstracts regarding EUVE-related data have recently been
accepted for publication:
EXTREME ULTRA VIOLET PLASMA DIAGNOSTIC: A TEST USING EUVE CALIBRATION DATA
M. Landini (Universita di Firenze, Italy) and B.C. Monsignori Fossi
(Osservatorio Astrofisico di Arcentri, Italy)
Astonomy and Astrophysics, 275, L17-L20 (1993)
The theoretical Xray-EUV spectral code of Landini and Monsignori Fossi
(1990) has been compared with an emission spectrum of the active late type
star AU Mic obtained during the initial calibration phase of Extreme Ultra-
violet Explorer Spectrometer. This comparison has been used to test the
overall applicability of the code and to provide inputs for improvement. A
number of lines were identified in the spectrum of AU Mic including several
highly ionized iron lines.
Key words: stars; coronae; EUV radiation; emission lines identification
---------------------------------------------------
THE EXTREME ULTRAVIOLET EXPLORER SPECTRUM OF ALPHA AURIGAE (CAPELLA)
A.K. Dupree (CfA), N.S. Brickhouse (CfA), G.A. Doschek (NRL), J.C. Green
(CASA), and J.C. Raymond (CfA)
Ap. J. Letters, V417, 20 Nov 1993 (in press)
Extreme ultraviolet spectra (70-740 A) of the bright spectroscopic binary
system Capella (Alpha Aurigae), obtained with the Extreme Ultraviolet Explorer
satellite (EUVE), show a rich emission spectrum dominated by iron emission
lines: Fe XV-XXIV. The emission measure for the system reveals a continuous
distribution of plasma temperatures between 1e5 and 1e7.8 K, with a clear
minimum near 1e6 K and a local maximum at 6e6 K. Electron density diagnostics
based on Fe XXI indicate N_e ~= 4e11 to 1e13 cm^(-3) at T_e = 1e7 K.
Subject headings: stars: chromosphere -- stars: giant -- stars: mass-
loss -- stars: individual (Alpha Aurigae)
---------------------------------------------------
EARLY WHITE DWARF RESULTS FROM EUVE
D.S. Finley (CEA/UCB), Frits Paerels (UCB) and Detlev Koester (LSU)
In White Dwarfs: Advances in Observation and Theory, ed. M.A. Barstow,
Dordrecht: Kluwer Academic Publishers, pp. 191-203, 1993
Following the recent launch of the Extreme Ultraviolet Explorer satellite
(EUVE), several white dwarfs were observed (both photometrically and spectro-
scopically) as part of the In-Orbit Checkout (IOC) activities which were
carried out prior to the start of the sky survey, and also during pointed
observations which were performed during the course of the sky survey. Our
initial assessment of the data has included comparison of the EUVE measure-
ments with model predictions, and a cross-comparison of the results of analy-
ses of EUV data from EUVE, the ROSAT Wide Field Camera (WFC), and EXOSAT. The
results suggest that the in-flight results for EUVE are consistent with the
EUVE ground calibration. Comparing results for pure H white dwarfs from EUVE
with results from the WFC, we find that similar temperature ranges are ob-
tained. There is an apparent systematic bias toward larger interstellar co-
lumns for the WFC which gives columns about 0.3 dex greater than are obtained
from EUVE. We found large systematic differences between EUVE and EXOSAT.
We used the HUT and EXOSAT spectroscopic observations of HZ43 to perform a
provisional adjustment of the EXOSAT effective areas which significantly
reduced that difference. We have also analyzed EUVE photometric observa-
tions of two metal-rich hot DA white dwarfs, GD246 and G191-B2B, and we pre-
sent the first determination of metal abundances for them based on EUV mea-
surements.
---------------------------------------------------
THE EXTREME ULTRAVIOLET EXPLORER BRIGHT SOURCE LIST
R.F. Malina, H.L. Marshall, B. Antia, C.A. Christian, C.A. Dobson,
D.S. Finley, A. Fruscione, F. Girouard, I. Hawkins, P. Jelinsky, J. Lewis,
J. McDonald, K. McDonald, R.J. Patterer, V. Saba, M.M. Sirk, B.A. Stroozas,
J.V. Vallerga, P.W. Vedder, A. Wiercigroch, and S. Bowyer (CEA/UCB)
Astronomical Journal, Feb 1994 (in press)
Initial results from the analysis of the Extreme Ultraviolet Explorer (EUVE)
all-sky survey (58-740 A) and deep survey (67-364 A) are presented through the
Bright Source List (BSL). The BSL contains 356 confirmed extreme ultraviolet
(EUV) point sources with supporting information, including positions, observed
EUV count rates, and the identification of possible optical counterparts. One
hundred twenty-six sources have been detected longward of 200 A.
6. EGO Program Notes Regarding the Deep Survey/Spectrometer Instruments
=======================================================================
by Anne Miller (EGO Technical Writer)
Improved Signal-to-Noise Ratio After Spectrometer Detector Threshold Changes
----------------------------------------------------------------------------
The first assessment of the spectrometer background rates after changes
in the upper and lower software thresholds in the short- (SW) and medium-
wavelength (MW) detectors, which went into effect on 22 July 1993 indicate
that spectrometer backgrounds have dropped as expected, and the MW "smudge"
has disappeared.
After one year, some detectors were showing decreased gain, particularly
in areas which consistently saw high count rates, such as the 304 A feature
in the MW spectrometer. The hardware threshold levels were lowered to admit
the lower pulse height EUV events and eliminate some of the high energy par-
ticle background. Calibrations of Telescope Interface (TIF) deadtime were
preserved by changing the software thresholds as well.
The mean count-rate/pixel/second during the latest calibration observation
of AU Mic on 23 July 1993 was calculated for sample areas near the spectra,
and in shadowed areas where nearly all counts result from particle detections.
The statistics were compared to the same calculations made from the first ob-
servation of AU Mic a year earlier, begun on 14 July 1992.
The results showed that spectral backgrounds in the SW and MW detectors
have decreased by 35-50%, while the long-wavelength (LW) background levels
matched those of the previous observation. The count rates of airglow features
were also unaffected. Although this test is based on a single observation,
comparable decreases in background are likely to continue. The LW detector
thresholds were lowered slightly on 12 October, and backgrounds will be tested
in the next few weeks.
Tests of Dithered Pointing to Alleviate Fixed Pattern Noise
-----------------------------------------------------------
The microchannel plate detectors used in the EUVE spectrometers exhibit
a small-scale distortion which can appear in extracted spectra as semi-regular
spatial variations in the apparent sensitivity over a period of about 17
pixels. This spatial variation is caused by distortions in the microchannels
at the outside boundaries of subregions. At the subregion boundaries, the
packing of fiber bundles during manufacture of the microchannel boule distorts
some channels. The distorted channel cross-sections in turn cause shifts in
the apparent locations of events at the subregion boundaries.
Obtaining reliable flat fields for the spectrometer is impractical due to
the integration times involved. The EGO program is therefore testing the prac-
ticality of dithering the pointing slightly during an observation to "wash
out" the effects of fixed pattern noise in the spectrum.
The dithering tests will involve a small slew, on the scale of two arc
minutes, during each orbit daytime when detectors are turned off. As the
excursions will be well within the area of stability for the wavelength
solution, the effects of the dithering can be completely removed from the
spectra during standard processing with the EGO Center event pipeline, using
the reported spacecraft aspect.
Following the tests, the effectiveness of dithering will be evaluated and
guidelines will be formulated based on the results, the effects of the fixed
pattern noise on different types of observations, and the frequency of slewing
available to the spacecraft.
Analysis of Deep Survey Detector Dead Spot
------------------------------------------
Comparison of initial IOC calibrations with recent observations of white
dwarfs has shown the development of a small area of decreased gain near the
center of the deep survey (DS) detector. Shifts of the image position by as
little as 3 pixels (13 arc seconds) resulted in the Lexan/B count rate decli-
ning by as much as a factor of three. The dead spot is the result of intense
bombardment by EUV photons from bright sources, and has been observed in orbits
as early as the initial slew to HZ43 on 18 February of this year.
GO's who have received DS detector photon data and centroids from observa-
tions made after 18 February 1993 should treat all DS detector count rates as
suspect. Members of the CEA data analysis and science teams are developing a
method that will use maps of the dead spot (to be obtained during the aspect
dithering tests mentioned above), and observation aspect records to estimate
the fraction of DS counts that were lost during such observations. Spectro-
meter count rates are not affected.
At least a partial recovery of the detector gain in the dead spot is ex-
pected, but the rate of recovery is yet to be determined. In the meantime,
pointings in the next EUVE science plan, scheduled to begin after 18 November,
will be offset by one arc minute to avoid the dead spot. The spectrometer
wavelength solution is stable up to nearly one degree from boresight, so this
should have no noticeable effect on GO data quality.
-----------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme
Ultraviolet Astrophysics, University of California, Berkeley, CA 94720,
USA. The opinions expressed are those of the authors. Publishers:
Drs. R. Malina and C. Stuart Bowyer. Editor: B. Stroozas. Funded by
NASA contracts NAS5-30180 and NAS5-29298. Send newsletter correspondence
to: ceanews@cea.berkeley.edu. The EUVE Public Science Archive is available
via anonymous FTP: cea-ftp.cea.berkeley.edu, pub/archive. The EUVE project
is managed by NASA's GSFC. The GSFC Project Manager: Paul Pashby, Project
Scientist: Dr. Yoji Kondo, Deputy Project Scientist: Dr. Ronald Oliversen.
NASA HQ Program Scientist: Dr. Robert Stachnik, Deputy Program Scientist:
Dr. D. Buzasi, Program Manager: Dr. G. Riegler. GSFC Project Operations
Director: Mr. Kevin Hartnett. Information on the EUVE Guest Observer
Program is available from: Dr. Y. Kondo, Mail Code 684, GSFC, Greenbelt,
MD 20771 (301)286-6247; email to euve@stars.span.nasa.gov.
END-----EUVE---------ELECTRONIC---------------NEWS-----------------END
% ====== Internet headers and postmarks (see DECWRL::GATEWAY.DOC) ======
% Date: Fri, 5 Nov 93 17:31:53 PST
% From: EUVE Electronic Newsletter distribution <ceanews@cea.Berkeley.EDU>
% To: euvenews@imperial.berkeley.edu
% Subject: EUVE Electronic Newsletter
|
| 770.30 | EUVE Newsletter - December 6 | VERGA::KLAES | Quo vadimus? | Wed Dec 08 1993 18:37 | 425 |
| From: US1RMC::"ceanews@cea.Berkeley.EDU" "EUVE Electronic Newsletter
distribution" 6-DEC-1993 20:06:53.19
To: euvenews@cea.Berkeley.EDU
CC:
Subj: EUVE Electronic Newsletter
EEEEEEEEEEE U U V V EEEEEEEEEEE
E U U V V E
E U U V V E
EEEEEEE U U V V EEEEEEE
E U U V V E
E U U V V E
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
------------------------------------------------------------------
Vol 3, No. 16 December 6, 1993 ISSN 1065-3597
------------------------------------------------------------------
Notes from the Editor
=====================
by Brett A. Stroozas, DASS/Archive Manager
Welcome to this addition of the electronic newsletter for the Extreme Ultra-
violet Explorer satellite (EUVE). The mission is now in the 11th month of the
Guest Observer (GO) phase in which EUVE makes long-exposure spectroscopic ob-
servations of specific NASA-approved GO targets. The satellite continues to
perform extremely well. This issue of the EUVE electronic newsletter, which
is compiled and published at the Center for EUV Astrophysics (CEA) in Berkeley,
CA, contains the following:
1. an introduction to the EUVE User's Committee
2. abstracts of recently accepted EUVE-related science papers
3. news from the EUVE Guest Observer (EGO) group
4. news from the CEA Educational Outreach program
5. news regarding the EUVE CD-ROM series
6. listing of available jobs at CEA
Please send any comments and/or suggestions related to this newsletter to
ceanews@cea.berkeley.edu (Internet).
1. EUVE User's Committee Members
================================
The EUVE User's Committee (formally known as the EGOWG -- EUVE Guest Obser-
ver Working Group) was established as an advisory committee to NASA Headquar-
ters regarding all aspects of the EUVE Guest Observer Program. The group meets
periodically to review the EGO Center progress (e.g. in software development)
and to comment on future plans. As announced in last month's newsletter, the
next EUVE User's Committee meeting will be held at the American Astronomical
Society (AAS) Conference on Thursday, 13 January 1994, for everyone interested
in extreme ultraviolet astronomy (members of the user community are encouraged
to attend). The current members of the Users' Committee are as follows:
Name Affiliation E-mail Address
---- ----------- --------------
Shipman, Harry (Chair) U. of Delaware eod00391@udelvm.udel.edu
Bagenal, Fran U. of Colorado bagenal@pele.colorado.edu
Bruhweiler, Fred Catholic U. of America bruhweiler@iue.dnet.nasa.gov
Cassinelli, Joe U. of Wisconsin cassinelli@macc.wisc.edu
Dupree, Andrea SAO dupree@cfa.harvard.edu
Holberg, Jay U. of Arizona holberg@looney.dnet.nasa.gov
Howell, Steve Plan. Science Inst. howell@5470.dnet.nasa.gov
Judge, Phil NCAR judge@hao.ucar.edu
Nousek, John Penn St. U. nousek@astro.psu.edu
For more information regarding the members and/or activities of the User's
Committee, please contact the EGO group at egoinfo@cea.berkeley.edu (Internet).
2. Abstracts of Recently *Accepted* EUVE Papers
===============================================
Included below are abstracts of EUVE-related papers recently *accepted* for
publication in refereed journals. GOs are invited to contribute accepted ab-
stracts for inclusion in future editions of this newsletter. Abstracts should
be sent to egoinfo@cea.berkeley.edu.
--------------------------------------------------------------
LOW DENSITY OF NEUTRAL HYDROGEN AND HELIUM IN THE LOCAL ISM: EUVE PHOTOMETRY
OF THE LYMAN CONTINUUM OF THE HOT WHITE DWARFS MCT 0501-289, MCT 0455-281,
HZ 43, and GD 153
S. Vennes, J. Dupuis, S. Bowyer, G. Fontaine, A. Wiercigroch, P. Jelinsky,
F. Wesemael, and R.F. Malina
to appear in Astrophysical Journal Letters
The first comprehensive sky survey of the extreme ultraviolet (EUV) spectral
range performed by the Extreme Ultraviolet Explorer (EUVE) has uncovered a
handful of very bright sources at wavelengths longer than the HeI 504 A photo-
ionization edge. Among these objects are four white dwarfs with exceptionally
low interstellar medium (ISM) column densities along the line of sight. Anal-
ysis of EUV photometry of the He-rich DO white dwarf MCT 0501-2858 and the
H-rich DA white dwarf MCT 0455-2812 along one line of sight and of the DA
white dwarfs HZ 43 and GD 153 near the north Galactic pole indicates that the
overall minimum column density of the neutral material centered on the Sun is
N_(HI) = 0.5-1.0e18 cm^(-2). In the case of MCT 0501-2858, EUV photometric
measurements provide a clear constraint to the effective temperature (60000-
70000 K). Given these neutral hydrogen columns, the actual contribution to
the density of neutral species from the immediate solar environment (the "local
fluff") would only cover a distance of ~2-3 pc (assuming an average density
n__(HI) = 0.1 cm^(-3)) leaving these lines of sight almost entirely within the
hot phase of the ISM. A preliminary examination of the complete EUVE long
wavelength survey indicates that these lines of sight are exceptional and set
a minimum column density in the solar environment.
Subject Headings: ISM: abundances -- ISM: structure -- ultraviolet: stars
-- white dwarfs
--------------------------------------------------------------
DETECTION OF ROTATIONAL MODULATION IN THE CORONAL EUV EMISSION FROM V711 TAURI
J.J. Drake, A. Brown, R.J. Patterer, P. Vedder, S. Bowyer, and E.F. Guinan
to appear in Ap. J. Lett.
The RS CVn binary V711 Tauri was observed by the Extreme Ultraviolet
Explorer satellite (EUVE) twice during the latter half of 1992, for periods
lasting several days. Light curves for the waveband 60-180 A derived from
the all-sky survey scanning in August, and from a pointed calibration
observation made in October, both exhibit a modulation of about 40%. The
modulation in both data sets is very similar, with minimum flux occurring
near orbital phase phi=0.5. Analysis using a two temperature optically thin
plasma emission model reveals that most of the detected extreme ultraviolet
(EUV) flux emanates from hot (~1e7 K) coronal plasma. The modulation is pro-
bably mostly due to either flare-like activity or to rotational occultation
of a long-lived, compact and especially bright coronal structure on the more
active star of the system. The phased data support the latter hypothesis.
This coronal structure is then likely to be associated with the persistent
spot patterns seen on V711 Tau when using Doppler and photometric surface
imaging techniques. Comparison with contemporaneous Stromgren b-band photo-
metry indicates that the optical minimum light leads the EUV maximum light
by 90 degrees in phase.
Subject Headings: stars: activity -- coronae -- late-type -- binaries: close
-- X-rays: stars
--------------------------------------------------------------
List of CEA EUVE-Related Abstracts for January AAS Meeting:
-----------------------------------------------------------
1. Implications of Initial Results from the EUVE Observatory for the FUSE EUV
Spectrometer and a Possible EUVE Extended Mission
R.F. Malina, D. Finley, J. Warren, A. Fruscione, J. Edelstein, and B. Haisch
2. Hands-on Demonstration of the Extreme Ultraviolet Explorer Satellite Orbit
I. Hawkins and R.F. Malina
3. Expansion of the EUVE Science Archive: New Products and Services
E. Polomski, B. Stroozas, J. Drake, K. Chen, and T. Chen
4. A Low Cost Approach to EUVE Spacecraft Operations: The Future in Astro-
physical Satellite Operations?
D. Biroscak, P. Ringrose, M. Samuel, G. Wong, L. Wong, J. Din, F. Kronberg,
and D. Meriwether
5. Preliminary Results of the EUVE Right Angle Program
K.E. McDonald, N. Craig, M.M. Sirk, J.J. Drake, and R. F. Malina
6. Possible Detection of a Nearby Supernova Remnant at High Galactic Latitudes
R. Lieu, C. Hwang and S. Bowyer
7. Extreme Ultraviolet Observations of AGNs and BL Lac Objects
T.E. Carone and A. Fruscione
8. EUVE Observations of Planetary Nebulae
A. Fruscione, M. Abbott, J.J. Drake, J. Dupuis, R.F. Malina, M. Mathiou-
dakis, K. McDonald, and K.C. Chu
9. EUV emission from the low activity dwarf HD 4628
M. Mathioudakis, J.J. Drake, J.H.M.M. Schmitt, K. McDonald, and S. Bowyer
10. Coronal Variability in the Extreme Ultraviolet
J.J. Drake, M. Mathioudakis, J.P. Pye, A. Fruscione, S. Bowyer,
P.W. Vedder, and R.J. Patterer
11. EUVE Spectroscopic Observation of the 1992 July 15 Flare on AU Mic
M. Abbott, S. Cully and G. Fisher
12. The First EUVE Source Catalog
J. Lewis, S. Bowyer, R. Lieu, M. Lampton, X. Wu, J.J. Drake,
and R.F. Malina
13. Spectroscopic and Orbital Properties of the Binary Feige 24 and Discovery
of External Plasma at Inferior Conjunction
S.Vennes and J.R.Thorstensen
14. Discovery of Strong EUV-induced Balmer Emission in the New WD+dM Binary
EUVE J2013+40.0 (RE 2013+400)
J.R. Thorstensen and S. Vennes
15. The Luminosity Function of Hot DA White Dwarfs from an EUV-Selected Sample
J. Dupuis, S. Vennes and S. Bowyer
3. Notes from the EUVE Guest Observer (EGO) Program
===================================================
3.1 Spectrometer Dithering Test Results
by Anne Miller, EGO Technical Writer
The problem of fixed pattern detector noise in the spectrometer can intro-
duce spurious features in observations of bright sources. To alleviate this
effect in the absence of usable flat field images, the EGO Center has conducted
experiments in which the spectrometer pointing was "dithered," by moving the
spectrometer each orbit to one of 30 randomly chosen pointings within a radius
of 1 arc minute. This effectively "washes out" the fixed patterns caused by
deformed micro-channels. The pointing errors were corrected by the standard
EGO Center data processing to refocus the spectra.
The results from a dithered observation of the white dwarf G191-B2B were
compared to a previous observation of the same star, and the signal to noise
for the medium wavelength spectrum was increased by more than a factor of two.
The agreement between flux measurements performed in the overlapping regions of
the medium- and long-wavelength channels was also greatly improved. The EGO
Center will recommend dithering for other sources based on source brightness
and other criteria.
3.2 Earth Blockage
by Anne Miller, EGO Technical Writer
The pointing range of the Deep Survey/Spectrometer (DS/S) was increased
after tests last August to include angles of up to 90 degrees from anti-sun.
The increased pointing range means it is also more likely that the earth will
impinge on the spectrometer's line-of-sight during parts of some pointed ob-
servations. The EGO center recommends that GO's whose observations were made
after the mini-IOC in August check their data for signs of earth blockage.
If earth blockage has occurred during orbit nighttime, this will change the
effective exposure time, and any flux measurements made with the uncorrected
exposure will be on the low side.
Earth blockage is defined by a simple geometrical condition, and there are
two ways to search the data for its occurrence. Blockage can be defined in
terms of the angle between the satellite zenith and the DS/S pointing vector,
the quantity called "DSSZEN" which can be calculated from the telemetry tables
by the IRAF/EUV task BACKMON.
It is assumed that looking through the earth's atmosphere 200 Km above the
earth's surface will produce an unacceptable attenuation of EUV source flux.
The conditions under which blockage occurs depend on the atmospheric altitude
(A) up to which the line of sight is considered blocked, the earth's radius
(Re), and the mean height (H, ~516 Km) of the satellite above the earth.
Re + A
DSSZEN > 180 - B, where: tan(B) = --------
Re + H
For values of A from 200 to 450 Km, the value of 180-B ranges from 136.35 to
135.28 degrees.
GO's should first run BACKMON using their telemetry tables to produce the
DSSZEN angle, and search for periods when this angle exceeds their chosen li-
mit. This can be easily done using the task DQSELECT to display DSSZEN from the
table produced by BACKMON, setting an upper limit, and creating a table of good
times in conjunction with the standard limits on detector ADC counts.
A second test for earth blockage would be to create a light curve from the
HeII 304 A airglow feature in the medium wavelength channel. The airglow should
show a marked decrease if the earth limb enters the line of sight, and should
drop to nearly zero for periods when full blockage occurs.
3.3 Error in GO Flux Values from the DS/S Scanner
by Kelley McDonald, Data Analysis Support Staff
and Jean Dupuis, EGO Center Scientist
The flux values computed from the Deep Survey data for all Guest Observer
targets processed before 3 Dec 1993 are incorrect. The grasp values that were
used to convert count rate to flux were out-of-date and incorrect. All Guest
Observers that have received these data can compute the correct flux values by
multiplying the received fluxes by 0.5748 -- the ratio of the old grasp value
to the new one. Errors in the fluxes will also need to be multiplied by this
factor. The units of the fluxes and errors are ph/cm^2/s/A.
3.4 EUVE on the World Wide WEB
by Anne Miller, EGO Technical Writer
The EUVE Guest Observer Center at CEA now has a home page in the NCSA MOSAIC
Web browser. The World Wide Web is a network-spanning communications program
that transmits hypertext documents and images in standard formats.
X windows users running MOSAIC can visit the CEA home page, access the CEA
anonymous ftp site, "gopher" server, and an operations page that supplies
weekly reports on EUVE and proposal database information. GO proposals in the
database can be accessed by proposal number, target name, observation date, or
Principal Investigator (PI) name. Experimental (use at your own risk!) services
include a target visibility test for EUVE pointed observations and facilities
to register for various EGO Program electronic mailing lists.
The CEA home page Uniform Resource Locator (URL) is:
http://cea-ftp.cea.berkeley.edu/
and can be entered from the NCSA "What's New" page under "What's New for Octo-
ber" (about a third of the way down the page).
4. CEA Educational Outreach Efforts
===================================
by Nahide Craig, Data Analysis Support Staff
[Editor's note: In order to provide educational opportunities, particularly in
lieu of NASA's interest in promoting educational outreach with K-12 audiences,
CEA has established an educational outreach program. Included below are news
notes on two areas of this effort.]
4.1 FAX Friends
The first EUVE Education Outreach Advisory Board met at CEA on 23 November
1993. In addition to encouraging CEA staff to participate in educational out-
reach efforts, a major outcome of the meeting was the establishment of a part-
nership for educational opportunities between CEA and one member of the Board,
the associate superintendent of the Lodi Unified School District (LISD), who
immediately directed CEA to some of the LISD special programs (e.g., a special
technical high school for the underachieving, an underserved gifted minority
students program and a gifted program in one of the elementary schools).
To be immediately implemented is the "FAX Friends" concept. The idea
here is for CEA members to give a presentation on EUVE in a chosen LISD school
in order to spark interest in Space Science and Astronomy and to start a dialog
with students and teachers. A FAX machine will then be used to conduct ques-
tion-and-answer correspondence between the school and the CEA community.
4.2 Project ASTRO Parters
Drs. Isabel Hawkins and Nahide Craig have established a partnership with
two 5th grade teachers at the Sequoia Elementary School in Oakland, CA. This
partnership is part of the Astronomical Society of the Pacific's Project ASTRO,
a state-wide project that links amateur and professional astronomers with
teachers and students in grades 4-9. The relevant partners attended a 2-day
Project ASTRO training workshop in October at Stanford University and are
currently working together to plan activities and projects in, and out, of
the classroom.
Two classroom meetings in the Oakland elementary school have already been
held. The purpose of the first meeting, which was devoted to Astronomy as a
career, was to raise interest in Astronomy and serve as an ice-breaker between
students/teachers and the astronomers. A slide show of Craig and Hawkins as
working astronomers, and another on celestial objects was followed by lively
question and answer sessions.
In the second meeting, the phases of the Moon were demonstrated. The stu-
dents, using the results of previous homework assignments in which they made
and recorded observations of the Moon, proposed their ideas on the causes of
the phase phenomena. Each student then participated in a visual demonstration
-- using a 200 watt light bulb as th Sun, their head as the Earth and a sty-
rofoam ball as the Moon -- which displayed the Moon's phases as it orbits the
Earth. Another discussion was then held to discuss what was observered and
learned.
The next visit will include a Tour of the Solar System to compare and study
the Planets.
5. EUVE Science Archive Notes: Second Installment in the EUVE CD-ROM Series
============================================================================
by Brett A. Stroozas, DASS/Archive Manager
As the EUVE mission moves into 1994, the proprietary data rights associated
with EUVE data will begin to expire. GO observations begin to go public in
April, 1994, and the all-sky survey data will follow in August. In preparation
for these milestones, and in order to make this data easily accessible to the
astronomical community, the EUVE Science Archive group is bustling with acti-
vity. Operationally, the Archive has been established to distribute and make
accessible EUVE-related data and services via a variety of methods including
the CEA anonymous ftp site, the CEA node of NASA's Astrophysics Data System
(ADS) and the EUVE CD-ROM series (the implementation of network tools such as
Mosaic, gopher and WAIS is also underway). This article focuses on the next
upcoming installment in the CD-ROM series.
As many of you know, Volume 1, Number 1 of the EUVE CD-ROM series was re-
leased at the June, 1993, AAS in Berkeley, CA. This disc contained various
EUVE-related data, software and documentation, highlighted by a GO observation
of the late-type star AT Mic.
The Archive group is presently in the final production stages for Volume 2,
Number 1 (A,B and C) of the CD-ROM series which is to distributed at the Janu-
ary, 1994, AAS meeting in Washington, D.C. For this set of three CDs, NASA has
approved the early release of 11 GO calibration observations from the in-orbit
calibration and all-sky survey phases of the mission. These observations have
been arranged thematically on the three discs as follows:
o disc A contains the four White Dwarfs WD1845+019 (observed on 06/28/92,
exposure of approximately 27 ksec), Feige 24 (11/20/92, 58 ksec),
G191-B2B (12/15/92, 45 ksec), and WD0549+158 (01/10/93, 60 ksec)
o disc B contains the two Late-type stars Capella (12/12/92, 75 ksec) and
Procyon (01/15/93, 97 ksec)
o disc C contains five assorted targets including the White Dwarf WD1620-391
(06/25/92, 32 ksec), the Cataclysmic Variable RE1938-461 (07/09/92,
40 ksec), the BL Lac object PKS2155-304 (07/21/92, 34 ksec), the Late-
type star HR1099 (10/24/92, 75 ksec), and the Moon (12/10/92, 1.5 ksec)
In addition to the relevant GO data sets, each disc will also contain:
o software -- the latest versions of the EGO Center software and reference data
used to process the included observations
o all-sky survey data -- the full text, figures and tables for the two survey
papers:
(1) The Extreme Ultraviolet Explorer Bright Source List
Malina, R.F., et al.
Astronomical Journal, February 1994 (in press)
(2) The First EUVE Source Catalog
Bowyer, C.S., et al.
Astrophysical Journal Supplement (submitted)
(These papers are also available in the CEA ftp site.)
o assorted documentation -- includes past issues of this newsletter, abstracts
of CEA EUVE papers, some overview articles regarding specific aspects
of the mission (as taken from the special EUVE edition of the Journal
of the British Interplanetary Society, 46(9), September, 1993), and
other miscellaneous mission-related documents
Planning for the long-term CD distribution will begin shortly. The Archive
group would appreciate any comments and/or suggestions from you, the user com-
munity, regarding ways in which EUVE data could best be presented on CD to make
them most useful scientifically.
To obtain more information regarding the EUVE Science Archive, please send
e-mail to archive@cea.berkeley.edu (Internet) and include the word "help"
(quotes omitted) as the body of the message. A mailserver program will process
your request and send you the relevant information. All non-standard mail
requests are routed to CEA personnel who will handle any special requests or
comments. In addition, much of the data described above is also available on
the CEA anonymous ftp site which can be reached at cea-ftp.cea.berkeley.edu.
Again, the Archive group is working hard to provide useful data, services and
documentation to the astronomical community and would appreciate any comments
and/or suggestions for improvement.
6. CEA Job Listings
===================
by Cathie Jones, CEA Personnel Manager
Management Services Officer
Independently manage all business functions for the Center for EUVE Astro-
physics. Oversee the development and implementation of the following areas:
accounting, human resources, editorial services, contracts and grants admini-
stration, public relations, purchasing, facilities management and office
management. Financial analysis, budget and manpower planning required. Su-
pervisory and managerial experience required, preferably in a research envi-
ronment with hands-on project responsibility. Government contract negotiation
skills desired. UC experience in financial and personnel administration
helpful. Salary $37800 - $47200. EEO/AA.
For additional information, call Cathie Jones at (510) 642-1263.
-----------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme
Ultraviolet Astrophysics, University of California, Berkeley, CA 94720,
USA. The opinions expressed are those of the authors. Publishers:
Drs. R. Malina and C. Stuart Bowyer. Editor: B. Stroozas. Funded by
NASA contracts NAS5-30180 and NAS5-29298. Send newsletter correspondence
to: ceanews@cea.berkeley.edu. The EUVE Public Science Archive is available
via FTP: cea-ftp.cea.berkeley.edu, pub/archive. The EUVE project is
managed by NASA's GSFC. The GSFC Project Manager: Paul Pashby, Project
Scientist: Dr. Yoji Kondo, Deputy Project Scientist: Dr. Ronald Oliversen.
NASA HQ Program Scientist: Dr. Robert Stachnik, Dep. Program Scientist:
Dr. D. Buzasi, Program Manager: Dr. G. Riegler. GSFC Project Operations
Director: Mr. Kevin Hartnett. Information on the EUVE Guest Observer
Program is available from: Dr. Y. Kondo, Mail Code 684, GSFC, Greenbelt,
MD 20771 (301)286-6247; e-mail to euve@stars.SPAN.NASA.GOV.
END-----EUVE---------ELECTRONIC---------------NEWS-----------------END
% ====== Internet headers and postmarks (see DECWRL::GATEWAY.DOC) ======
% Date: Mon, 6 Dec 1993 16:12:20 -0800
% From: EUVE Electronic Newsletter distribution <ceanews@cea.Berkeley.EDU>
% Message-Id: <199312070012.QAA27619@imperial.cea.berkeley.edu>
% To: euvenews@cea.Berkeley.EDU
% Subject: EUVE Electronic Newsletter
|
| 770.31 | Flash - December 9 | VERGA::KLAES | Quo vadimus? | Fri Dec 10 1993 18:12 | 133 |
| From: US1RMC::"ceanews@cea.Berkeley.EDU" "EUVE Electronic Newsletter
distribution" 10-DEC-1993 15:12:06.06
To: euvenews@cea.Berkeley.EDU
CC:
Subj: EUVE News Flash
EEEEEEEEEEE U U V V EEEEEEEEEEE
E U U V V E
E U U V V E
EEEEEEE U U V V EEEEEEE
E U U V V E
E U U V V E
EEEEEEEEEEE UUUUU V EEEEEEEEEEE
------------------------------------------------------------------
ELECTRONIC NEWS ***FLASH*** OF THE EUVE OBSERVATORY
------------------------------------------------------------------
Vol 3, No. 16a December 9, 1993 ISSN 1065-3597
------------------------------------------------------------------
Notes from the Editor
=====================
by Brett A. Stroozas, DASS/Archive Manager
This news "flash" is an addendum to the 6 December 1993 issue of the EUVE
newsletter (Volume 3, No. 16), and contains some minor corrections to that is-
sue. The Center for EUV Astrophysics (CEA) apologizes for any inconvenience
or confusion.
1. EUVE User's Committee Members
================================
This section of the newsletter opened as follows:
"The EUVE User's Committee (formally known as the EGOWG -- EUVE
Guest Observer Working Group) was established as an advisory
committee to NASA Headquarters regarding all aspects of the EUVE
Guest Observer Program."
The word "formally" should actually read "formerly"; "NASA Headquarters" should
read "the Project Scientist at Goddard Space Flight Center". These corrections
produce the following text:
"The EUVE User's Committee (formerly known as the EGOWG -- EUVE
Guest Observer Working Group) was established as an advisory
committee to the Project Scientist at Goddard Space Flight Center
regarding all aspects of the EUVE Guest Observer Program."
3. Notes from the EUVE Guest Observer (EGO) Program
===================================================
The text for sub-section 3.2 on Earth Blockage was incomplete and should be
replaced with the following:
-------------------------------------------------------------------------------
3.2 Earth Blockage
==================
by Anne Miller, EGO Technical Writer
The pointing range of the Deep Survey/Spectrometer (DS/S) was increased
after tests last August to include angles of up to 90 degrees from anti-sun.
The increased pointing range means it is also more likely that the earth will
impinge on the spectrometer's line-of-sight during parts of some pointed ob-
servations. The EGO Center recommends that GO's whose observations were made
after the mini-IOC in August check their data for signs of earth blockage.
If earth blockage has occurred during orbit nighttime, this will change the
effective exposure time, and any flux measurements made with the uncorrected
exposure will be on the low side.
Earth blockage is defined by a simple geometrical condition, and there are
two ways to search the data for its occurrence. Blockage can be defined in
terms of the angle between the satellite zenith and the DS/S pointing vector,
the quantity called "DSSZEN" which can be calculated from the telemetry tables
by the IRAF/EUV task BACKMON.
It is assumed that looking through the Earth's atmosphere 200 Km above the
Earth's surface will produce an unacceptable attenuation of EUV source flux.
The conditions under which blockage occurs depend on the atmospheric altitude
(A) up to which the line-of-sight is considered blocked, the Earth's radius
(Re), and the mean height (H, ~516 Km) of the satellite above the Earth.
Re + A
DSSZEN > 180 - B, where: sin(B) = --------
Re + H
For values of A from 200 to 450 Km, the value of 180-B ranges from 107.41 to
97.93 degrees. The value of H is an average of mean orbit apogee and perigee
for a typical observing week. GO's should bracket this value in their calcu-
lations, as well as making a determination of the maximum value of A that is
acceptable.
GO's should first run BACKMON using their telemetry tables to produce the
DSSZEN angle, and search for periods when this angle exceeds their chosen li-
mit. This can be easily done using the task DQSELECT to display DSSZEN from
the table produced by BACKMON, setting an upper limit, and creating a table
of good times in conjunction with the standard limits on detector ADC counts.
A second test for Earth blockage would be to create a light curve from the
HeII 304 A airglow feature in the medium wavelength channel. The airglow
should show a marked decrease if the Earth limb enters the line-of-sight, and
should drop to nearly zero for periods when blocked by the earth disk. The
behavior of the airglow light curve may help users fine tune the duration of
the Earth blockage more easily than the numerical calculations above.
-------------------------------------------------------------------------------
4. CEA Educational Outreach Efforts
===================================
The Editor's note for this section stated the following:
"[Editor's note: In order to provide educational opportunities,
particularly in lieu of NASA's interest in promoting educational
outreach with K-12 audiences, ..."
The phrase "in lieu of" should have read "in view of". It is important to em-
phasize that the EUVE project is working WITH NASA's interests and not against.
CEA apologizes for any confusion this statement may have caused.
-----------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme
Ultraviolet Astrophysics, University of California, Berkeley, CA 94720,
USA. The opinions expressed are those of the authors. Publishers:
Drs. R. Malina and C. Stuart Bowyer. Editor: B. Stroozas. Funded by
NASA contracts NAS5-30180 and NAS5-29298. Send newsletter correspondence
to: ceanews@cea.berkeley.edu. The EUVE Public Science Archive is available
via FTP: cea-ftp.cea.berkeley.edu, pub/archive. The EUVE project is
managed by NASA's GSFC. The GSFC Project Manager: Paul Pashby, Project
Scientist: Dr. Yoji Kondo, Deputy Project Scientist: Dr. Ronald Oliversen.
NASA HQ Program Scientist: Dr. Robert Stachnik, Dep. Program Scientist:
Dr. D. Buzasi, Program Manager: Dr. G. Riegler. GSFC Project Operations
Director: Mr. Kevin Hartnett. Information on the EUVE Guest Observer
Program is available from: Dr. Y. Kondo, Mail Code 684, GSFC, Greenbelt,
MD 20771 (301)286-6247; e-mail to euve@stars.SPAN.NASA.GOV.
END-----EUVE---------ELECTRONIC---------------NEWS-----------------END
% ====== Internet headers and postmarks (see DECWRL::GATEWAY.DOC) ======
% Date: Fri, 10 Dec 1993 11:10:38 -0800
% From: EUVE Electronic Newsletter distribution <ceanews@cea.Berkeley.EDU>
% To: euvenews@cea.Berkeley.EDU
% Subject: EUVE News Flash
|
| 770.32 | EUVE Extract from Goddard Weekly Report | CXDOCS::J_BUTLER | E pur, si muove... | Thu Dec 23 1993 10:25 | 164 |
|
The following information is from the GODDARD Weekly Report, December 10, 1993.
From Code 602, Orbiting Satellites Project.
EXTREME ULTRAVIOLET EXPLORER (EUVE)
NASA's Extreme Ultraviolet Explorer conducted another productive week of Guest
Observations with all subsystems performing nominally. A flight software
patch to reorient EUVE's solar arrays autonomously to avoid overheating from
solar specular reflection from the spacecraft body was successfully uplinked.
Observations planned for the coming week include the bright early winter star
Capella.
Spacecraft Status
Performance of the Explorer Platform was nominal this past week. No adverse
effect on the batteries has been seen as a result of the recent excessive
depth of discharge incident. A flight software patch designed to nominally
reorient the solar arrays after spacecraft slews was uplinked on the 29th and
appears to be working as designed. Some uplinked SPRU (Spacecraft Power
Regulation Unit) diagnostic TMONs (telemetry-monitors) were also successfully
uplinked and enabled this week. All other subsystems performed well.
Instrument Status
No adverse effects from the CDP shutdown of last week have been reported bu
UCB. Execute-On-Receipt (EOR) commands to optimize the detector settings for
last week's targets were processed by the payload electronics without
incident. Additionally, diagnostics were performed on detector #7 to check
the apparent dead spot in the boresight of that detector. The front flange
thernistor once again shows an "off" condition, but has shown anomalous
readings in the past and so no further action besides routine monitoring of
this telemetry point is planned.
Upcoming Events
EUVE will conduct observations of G 191 B2B, RE 0431, and GL 355 (also known
as HD-82558) in the coming week.
EARTH RADIATION BUDGET SATELLITE (ERBS)
The ERBS spacecraft is still operating with only one battery with two failed
cells. The SAGE science data was resumed after the full-sunlight period ended
last week. Also the ERBE-NS instrument remains ON after two weeks of
operations and it continues to collect excellent science data for the
NASA/LaRC experimenters. More than 60 instrument calibrations have been
performed on the ERBE-NS instrument in the last two weeks. The original plan
was to turn OFF the ERBE-NS instrument after the recent full-sunlight period
ended, but the Power Engineers indicate that there is still enough spacecraft
power to operate it for a while longer without damaging the spacecraft
battery. The orbital eclipses will reach a maximum and the spacecraft will be
yawed 180 degrees in less than two weeks. The spacecraft celebrates its
50,000th orbit later this week.
COSMIC BACKGROUND EXPLORER (COBE)
COBE continues to acquire all science and engineering data withour any major
problems or operational errors. The Project still plans to terminate all
science operations on DEcember 23rd after four full years of science
operations, and still plans to perform approximately thirty End-of-Life (EOL)
engineering tests during the last week in December and in the first three
weeks on January. After all these EOL tests are completed, the spacecraft
will be transferred to Wallops for their use as a test satellite.
SOLAR, ANOMALOUS, AND MAGNETOSPHERIC PARTICLE EXPLORER (SAMPEX)
SAMPEX also continues to acquire all science and engineering data without any
significant problems or operational errors. The spacecraft operations are
still being performaed in the SOTA (Special Operations and Test Area) on new
hardware and software. The SAMPEX Ops will remains in the SOTA for another
2-4 weeks while the regular SMEX (Small Explorer) Mission Operations Room
(MOR) is being upgraded with new hardware and software for the SAMPEX and FAST
missions. The Flight Ops Team continues to test a number of new SAMPEX and
FAST software systems, and continues to participate in a number of tests in
the preparation for the FAST mission. The FAST and the SAMPEX missions will
be operated by the same Flight Ops Team (FOT) from the same Control Center.
INTERNATIONAL COMETARY EXPLORER (ICE)
Support of the ICE spacecraft continues on a routine basis. During the week
of 11/29/93 through 12/05/93, 2 real time passes were supported with no
commands transmitted.
INTERPLANETARY MONITORING PLATFORM (IMP)
Support of the IMP-8 spacecraft continues on a routine basis. During the week
of 11/29/93 through 12/05/93, 7 real time passes were supported with 52
commands transmitted.
A spacecraft experiment anomaly was discovered to have taken place on
November22, 1993 at 1623Z. The IOF (Gurnett) experiment remains off after
numerous attempts to turn it back on were unsuccessful. Data from IPD during
the failure has been expedited toe the experimenter. An investigation of the
anomaly continues.
INTERNATIONAL ULTRAVIOLET EXPLORER (IUE)
Highlights
On December 5, the IUEOCC experienced several electrical power hits due to
storms in the local area. Two if these power hits occurred during camera
reads, necessitating the possible replay of images from Wallops Analog Tapes.
Operations
A total of 236 images were taken during the week:
Long Wavelength Primary (LWP) . . . . . . . . 116
Long Wavelength Redundant (LWR) . . . . . . . . 0
Short Wavelength Primary (SWP) . . . . . . . 120
Operational Effectiveness
Total Time Avilable : . . . . . . . . . . . . . . . . . . . . 6720 minutes
Minus losses due to:
Engineering Tests . . . . . . . . . . . . . . . . . . . . . . . 0
minutes
Spacecraft Problems . . . . . . . . . . . . . . . . . . . . 0
minutes
Ground System Problems . . . . . . . . . . . . . . . . . 0 minutes
Operations Problems . . . . . . . . . . . . . . . . . . . . . 0
minutes
Time used in Science Data Ops: . . . . . . . . 6720 minutes
Effectiveness . . . . . . . . . . . . . . . . . . . . . . . . . . .
.. . . . 100%
Problems and Concerns
The Control Center have been informed that SATCOM Service to Wallops Island
will be interrupted on January 8 from 1500Z to 1900Z while switching to a new
COMMSAT. Since this time period overlaps the first half of the US! shift,
support from Santiago has been requested to cover the outage.
COMPTON GAMMA RAY OBSERVATORY (GRO)
The final three GRO orbit reboost burns are scheduled for December 15, 16, and
17. Each one is being planned as a nominal 90-second burn: however, the last
burn may be shortened to optimize the orbit mean altitude at approximately 450
kilometers circular. As of December 6, the height of perigee was 409.4
kilometers and the height of apogee was 451.6 kilometers.
The Compton observatory is in normal pointing ,ode. The +Z axis was oriented
toward the GEMINGA science target on December 1. The observatory will remain
ot this attitude until the maneuver to the VIRGO 284+75 science target on
December 13.
Based on the number of packets of data delivered to the instrument teams from
the Packet Processor facility, the percentage of full-time coverage achieved
with 32 Kbps real-time data from November 28 through December 4 was 67
percent. An additional 13 percent coverage was achieved with the BATSE 1 Kbps
subset of data during this time.
The performance of the batteries continues to be monitored very closely, woth
power configurations adjusted as necessary. The observatory is functioning
normally with primary systems powered from modular power subsystem 2, which is
performing very well. Modular power subsystem 1 continues to support a
reduced load of mainly heaters.
Operational testing for engineering evaluation of the GRO Remote Terminal
System (GRTS) is underway. Solid lock was maintained during the first
five-minute contack on December6. The 32 Kbps real-time data path was from
the GRO high-gain antenna through TDRS-1 (TDZ) to the Remote Ground Relay
Terminal (RGRT) at Cangerra, Australia. From RGRT, the data were forwarded to
the Extended TDRSS Ground Terminal (ETGT) at the White Sands Complex in New
Mexico and on to the GRO Payload Operations Control Center (POCC) and Packet
Processor (Pacor) at GSFC. This contact successfully utilized for the first
time the GRO on-board flight software capability for loading ephemerides for a
fourth TDRS spacecraft and processing that information to point the high-gain
antenna to that TDRS. Previously, only ephemerides or the TDRS-East,
TDRS-West, and TDRS-Spare were used routinely.
Intermittent lock on data was experinced during a ten-minute GRTS contact on
December 7. Operational testingof GRTS support will continue while TDRS-1 is
drifting. TDRS-1 is expected to reach 85 degrees East longitude in early
February 1994. When GRTS becomes operational in February, it will provide a
significant increase in real-time coverage for GRO.
Steve A.
Stephen.Andrews@gsfc.nasa.gov
|
| 770.33 | February 9 | VERGA::KLAES | Quo vadimus? | Thu Feb 10 1994 14:05 | 280 |
| From: US1RMC::"ceanews@cea.Berkeley.EDU" "EUVE Electronic Newsletter
distribution" 9-FEB-1994 23:51:51.64
To: euvenews@cea.Berkeley.EDU
CC:
Subj: EUVE Electronic Newsletter
EEEEEEEEEEE U U V V EEEEEEEEEEE
E U U V V E
E U U V V E
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----------------------------------------------------------------------------
ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
----------------------------------------------------------------------------
Vol 4, No. 2 9 February 1994 ISSN 1065-3597
----------------------------------------------------------------------------
Notes from the Editor
=====================
by Brett A. Stroozas, Data Analysis Support Staff (DASS) and Archive Manager
Welcome to the electronic newsletter for the Extreme Ultraviolet Explorer
satellite (EUVE), which is compiled and published monthly at the Center for
EUV Astrophysics (CEA) in Berkeley, CA. The EUVE observatory continued to
perform extremely well throughout the month of January, completing observations
of the following Guest Observer (GO) targets: U Gem (a Target of Opportunity),
WD1057+719, 3C273, Geminga, RE1309+081, Alpha Vir, RE1252-291, RE1016-053, and
the Moon.
The contents of this issue of the EUVE electronic newsletter are as follows:
1. Notes from the EUVE Guest Observer (EGO) Center
2. Abstracts of Recently *Accepted* EUVE Papers
3. IAU Colloquium Announcement: Astrophysics in the Extreme Ultraviolet
4. Right-Angle-Program Results at AAS
5. Notes from the EUVE Public Science Archive
To comment on, make suggestions for, or request subscriptions to the EUVE
electronic newsletter, send e-mail to ceanews@cea.berkeley.edu (Internet).
1. Notes from the EUVE Guest Observer (EGO) Center
==================================================
1.1 First Attempt to Map Deep Survey Detector Dead Spot a Partial Success
-------------------------------------------------------------------------
by Anne Miller, EGO Center Technical Writer [Editor's Note: This article
is based on an internal memo by Martin Sirk, DASS Research Associate.]
It was recently reported in these notes (5 November 1993) that a "dead spot"
had developed on the EUVE Deep Survey (DS) detector. Development of an area
of decreased sensitivity near boresight appeared after observations of the
bright white dwarf HZ43 in February of 1993.
On 28 November 1993, the DS was pointed directly at the full Moon in an at-
tempt to gather data that could be used to map the extent and effective depth
of the dead spot. Unfortunately the pointing coincided with a total lunar e-
clipse, and the resulting count rates were neither constant nor as high as was
hoped. However some estimates of the dead spot's characteristics have been
derived from the Moon data.
The dead spot appears to be centered at X = 1033, Y = 1025 (+/- 1 pixel) in
DS detector coordinates. It is somewhat asymmetrical; the width of the con-
tour at 85% of normal efficiency is 60 pixels (2.3 arc-minutes) in X and 50
pixels (1.9 arc-minutes) in Y. This means that pointings made one arc-minute
off-boresight, which were made starting 18 November 1993, will not move the DS
image completely off the dead spot, and DS pigeonhole data obtained for those
pointings may have inaccurate centroids. [Editor's Note: A "pigeonhole" is an
EUVE data file which contains photon information from within a given radius of
a given position on the sky.] The maximum loss of efficiency near the center
of the spot is nearly 80%, based on the average sensitivity of areas far from
bore-sight.
More Moon pointings are being planned to obtain better data on the DS de-
tector center region. Recent observations of the object U Gem saw transient
high count rates, but do not seem to have affected DS sensitivity.
1.2 Processing of Spectrometer Photons
--------------------------------------
by Dr. Mark Abbott, EGO Center Scientist
As of 5:00 PM on 1 February 1994, the EGO group had processed 552,661,776
photons from pointed spectrometer observations.
2. Abstracts of Recently *Accepted* EUVE Papers
===============================================
Included below are abstracts of EUVE-related papers recently *accepted* for
publication in refereed journals. GOs are encouraged to contribute *accepted*
abstracts for inclusion in future editions of this newsletter. Abstracts
should be sent to egoinfo@cea.berkeley.edu.
--------------------------------------------------------------
THE EXTREME ULTRAVIOLET CORONAL SPECTRUM OF THE SOLAR-TYPE STAR CHI ORI
B. Haisch (UCB/CEA, Lockheed), J.J. Drake (UCB/CEA) and J.H.M.M. Schmitt (MPI)
Astrophysical Journal (Letters), 421:L39-L42, 1994 January 20
We present an extreme ultraviolet coronal spectrum of the solar-type star
chi Ori (G0V), one of the first spectra obtained as a guest observation using
the Extreme Ultraviolet Explorer (EUVE). This star is younger and more active
than the Sun. Since no large-scale flare activity was evident in the simul-
taneous deep survey EUV photometry, we simulated the spectrum using a solar
active region differential emission measure (DEM) together with the plasma
emissivity code of Mewe, Gronenschild and van den Oord (1985). The spectral
simulation was normalized to the soft X-ray flux (0.1 to 2.4 keV) observed
during the ROSAT all-sky survey and also to the EUVE all-sky survey Lexan/B
filter count rate to generate predicted counts in spectral bins in order to
identify lines and line blends in the observed spectrum. The difference be-
tween these two normalizations was found to be less than 20 percent. We also
compare both the observed and simulated spectra to the Capella observations
of Dupree et al. (1993). The accuracy of the emission code and of this spectra
simulation is demonstrated by its excellent fit to the high signal-to-noise
data in the short-wavelength spectrum of Capella. For chi Ori we conclude the
following: (1) apart from the He II lines, we do not see many of the expected
lines forming at log T <= 6.2; (2) in the range log T = 6.3-6.8 we find rea-
sonable agreement with a spectrum simulating the DEM of a solar active region;
(3) material appears to be present at temperature as hot as log T = 7.2 (Fe
XXIV).
--------------------------------------------------------------
ERRATA
This abstract citation listed in the 6 January 1994 issue was incorrect:
EXTREME ULTRAVIOLET SPECTROSCOPY OF PKS 2155-304
Antonella Fruscione, Stuart Bowyer (CEA/UCB) and Steven M. Kahn (U. Chicago)
to appear in Astrophysical Journal Letters, 1994
The correct citation is:
EXTREME ULTRAVIOLET SPECTROSCOPY OF PKS 2155-304
Antonella Fruscione, Stuart Bowyer (CEA/UCB), Arieh Konigl (U. Chicago),
and Steven M. Kahn (UCB/SSL)
to appear in Astrophysical Journal Letters, 1994
--------------------------------------------------------------
3. IAU Colloquium Announcement: Astrophysics in the Extreme Ultraviolet
=======================================================================
First Announcement
IAU COLLOQUIUM NO. 152
ASTROPHYSICS IN THE EXTREME ULTRAVIOLET
University of California, Berkeley
March 27-30, 1995
Sponsored by IAU Commissions 48, 29, 34, 42 and 44
Chaired by: Stuart Bowyer and Bernhard Haisch
Scientific Organizing Committee:
P.C. Agrawal, A. Dupree, G. Fontaine, E. Jenkins, R.F. Malina, R.
Mewe, Y. Kondo, J. Sahade, J. Schmitt, A. Vidal-Madjar, K. Yamashita
Partial list of topics:
Coronae of Cool Stars
White Dwarfs
Photospheres and Winds of Early-Type Stars
Accretion Driven Sources
The Interstellar Medium
Neutron Stars
Cataclysmic Variables
Supernova Remnants
Extragalactic Sources in the EUV
Solar System Observations
Theoretical Modeling and Laboratory Measurement of Plasma EUV Emission
Results of recent Missions (EUVE, ROSAT, HUT, DXRBS, ALEXIS)
If you wish to receive the second announcement and registration material
please contact Ms. Sharon Lilly by e-mail (iau152@cea.berkeley.edu) or FAX
(510-643-5660) and indicate whether you wish to receive future material
by e-mail or postal mail.
4. Right-Angle-Program Results at AAS
=====================================
by Kelley McDonald, DASS Research Associate
During the GO phase of the EUVE Mission, data are being collected with the
three all-sky survey telescopes (scanners) and the Deep Survey (DS) imaging
telescope (which points 90 degrees away from the scanners). The EUVE
Right-Angle-Program (RAP) involves (1) the scheduling of target observations
in the scanners during GO observations in the DS, (2) the analysis of the
resulting non-GO data sets and (3) the coordination of possible simultaneous
observations with ground based instruments. All three aspects of the RAP are
now implemented and in operation. The resulting data sets consist of discrete
pointings performed at a much deeper level than the all-sky survey, although
covering only a small fraction of the sky.
The preliminary RAP results were presented in a poster paper at January's
183rd meeting of the American Astronomical Society (AAS) in Washington, D.C.
Analysis of the data has so far yielded 89 sources from ~90 scanner and DS
fields-of-view, a large number of which are previously undetected EUV sources.
About 80% of these sources had count-rates less than 0.01 counts/second and 76
of the 89 sources were not detected according to the First EUVE Source Catalog
(Bowyer, 1994). Strategies are currently being investigated which will open
up the RAP externally to the general astronomical community.
5. Notes from the EUVE Public Science Archive
=============================================
by Elisha Polomski, Archive Research Associate
and Brett Stroozas, DASS/Archive Manager
The Archive CD-ROM effort was well received at the AAS meeting -- more than
350 copies of the EUVE CD-ROM V2.1 set (Stroozas, 1994) were distributed. The
Archive poster paper "Expansion of the EUVE Science Archive: New Products and
Services" was displayed at the conference and incited a number of queries, in-
cluding requests for the all-sky survey Catalog (Bowyer, 1994), for available
EUVE images and for copies of CD-ROM V1.1 (Drake, 1993). All of this material,
or related information, is available in the CEA Archive anonymous FTP site
(cea-ftp.cea.berkeley.edu). There were also a number of new subscriptions to
the EUVE Electronic Newsletter (ceanews@cea.berkeley.edu). Some additional
requests were for various CEA preprints (the CEA booth ran out!) which may be
obtained from the CEA editorial group (pub@cea.berkeley.edu).
On another note, the Archive continues to work hard to make EUVE data and
information available via Mosaic on the World Wide Web (WWW). The Archive has
received over 200 external queries since its inception on the Web in late De-
cember, 1993. We expect to see interest grow as additional material becomes
available in the coming months (e.g. as data rights begin to expire in the
Spring).
EUVE Archive Access Reminders
-----------------------------
* CEA WWW Server:
http://cea-ftp.cea.berkeley.edu (Mosaic)
telnet cea-ftp.cea.berkeley.edu 200 (lynx)
* NASA's ADS: contact ads@cuads.colorado.edu for account information
* CD-ROM Series: Volumes 1 and 2 (four separate CDs) are available
* anonymous FTP (or gopher): cea-ftp.cea.berkeley.edu
* e-mail: archive@cea.berkeley.edu (include word "help" -- quotes omitted
-- as body of message
* EUVE Electronic Newsletters: ceanews@cea.berkeley.edu (to subscribe)
* Postal Mail:
The EUVE Public Science Archive
Center for EUV Astrophysics
2150 Kittredge St.
Berkeley, CA 94720
510-642-3032 (voice) or 510-643-5660 (fax)
archive@cea.berkeley.edu
REFERENCES
==========
Bowyer, C.S., et al., The First EUVE Source Catalog, Astrophysical Journal
Supplement, 1994 (in press)
Drake, J.J., et al., The Extreme Ultraviolet Explorer Science Archive:
Selected Data and Software, Eds. S. Bowyer and R.F. Malina,
1:1 in the CD-ROM series (ISSN# 1069-7497), 1993
Dupree, A.K., et al., The Extreme Ultraviolet Explorer Spectrum of Alpha
Aurigae (Capella), Astrophysical Journal (Letters), V417, 20 November
1993
Stroozas, B.A., et al., The Extreme Ultraviolet Explorer Science Archive:
Selected Data and Software, Eds. S. Bowyer and R.F. Malina,
2:1 in the CD-ROM series (ISSN# 1069-7497), 1994
-----------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme
Ultraviolet Astrophysics, University of California, Berkeley, CA 94720,
USA. The opinions expressed are those of the authors. Publishers:
Drs. R.F. Malina and C.S. Bowyer. Editor: B.A. Stroozas. Funded by
NASA contracts NAS5-30180 and NAS5-29298. Send newsletter correspondence
to: ceanews@cea.berkeley.edu. The EUVE Public Science Archive is accessible
via FTP: cea-ftp.cea.berkeley.edu, /pub/archive. The EUVE project is
managed by NASA's GSFC. The GSFC Project Manager: Paul Pashby, Project
Scientist: Dr. Yoji Kondo, Deputy Project Scientist: Dr. Ronald Oliversen.
NASA HQ Program Scientist: Dr. Robert Stachnik, Dep. Program Scientist:
Dr. D. Buzasi, Program Manager: Dr. G. Riegler. GSFC Project Operations
Director: Mr. Kevin Hartnett. Information on the EUVE Guest Observer
Program is available from: Dr. Y. Kondo, Mail Code 684, GSFC, Greenbelt,
MD 20771 (301)286-6247; e-mail to euve@stars.span.nasa.gov.
END-----------EUVE------------ELECTRONIC---------------NEWS-----------------END
% ====== Internet headers and postmarks (see DECWRL::GATEWAY.DOC) ======
% Date: Wed, 9 Feb 1994 18:36:40 -0800
% From: EUVE Electronic Newsletter distribution <ceanews@cea.Berkeley.EDU>
% To: euvenews@cea.Berkeley.EDU
% Subject: EUVE Electronic Newsletter
|
| 770.34 | March 9 | JVERNE::KLAES | Be Here Now | Wed Mar 09 1994 20:18 | 516 |
| From: US1RMC::"ceanews@cea.Berkeley.EDU" "EUVE Electronic Newsletter
distribution 09-Mar-1994 1709" 9-MAR-1994 17:02:29.71
To: euvenews@cea.Berkeley.EDU
CC:
Subj: EUVE Electronic Newsletter
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
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Vol 4, No. 3 09 March 1994 ISSN 1065-3597
---------------------------------------------------------------------------
Notes from the Editor
=====================
by Brett A. Stroozas, Data Analysis Support Staff (DASS)
and Archive Manager
Welcome to the electronic newsletter for NASA's Extreme Ultraviolet
Explorer satellite (EUVE), which is compiled and published monthly by the
EUVE Public Science Archive group at the Center for EUV Astrophysics (CEA)
in Berkeley, CA. The EUVE observatory continued to perform extremely well
throughout the month of February, completing observations of the following
Guest Observer (GO) targets: PSR0437-37, DK UMa, Vela, PG1520+525, Ca-
pella, sigma CrB, WD1057+719, and AG Dra.
The contents of this issue of the EUVE electronic newsletter are as
follows:
1. GO Data Releases
2. EUVE User's Committee Meeting Notes
3. Abstracts of Recently *Accepted* EUVE Papers
4. EUVE Session at the RAS/EAS94 Meeting
5. "Space News" Highlights EUVE Innovation in Science Operations
6. SOMOWG Meeting Notes
7. Notes from the EUVE Public Science Archive
8. "egi" Notes for GOs
9. CEA Job Listings
To comment on, make suggestions for, or request subscriptions to the EUVE
electronic newsletter, send e-mail to ceanews@cea.berkeley.edu (Internet).
1. GO Data Releases
===================
1.1 GO Data Rights to Expire Starting in April, 1994
----------------------------------------------------
by Dr. Harry Shipman, EUVE User's Committee Chairman
For at least a decade it has been an astronomical tradition that GOs
have proprietary rights to their data for a year after receiving it. The
first data tapes for the EUVE Guest Observer (EGO) program were distribu-
ted in April, 1993 and so these data will begin to become public in April,
1994. Once GO data rights expire, the EUVE Public Science Archive will
distribute data for those publicly available targets to anyone requesting
them.
As you may know, it is critical in the current funding climate to dem-
onstrate that missions like EUVE continue to be scientifically productive.
Some of us may have had contact with a more sedate, slower-paced astron-
omical world inhabited by gentlemen astronomers (they were almost all men
in those days), each having drawers and closets full of data from which
nuggets of insight would occasionally emerge. This era is past. Many
people who have a great deal to say about the future of space science in
general -- and EUVE in particular -- are beginning to ask for results.
And so I encourage you to continue to produce and publish good science
from EUVE -- there are a lot of great insights which are coming about and
the world needs to know about them.
1.2 Distribution of Archival GO Data Sets
-----------------------------------------
by Brett A. Stroozas, DASS/Archive Manager
As proprietary data rights begin to expire for GOs in April, the EUVE
Public Science Archive is working with the EGO Center to make the relevant
full data sets publicly available to the astronomical community. The ten-
tative plan is to release data sets on the first of the month following the
month in which the data was delivered to the GO (and a year later, of
course). The Archive group is currently working with the EGO Center and
with Deputy Project Scientist Dr. Ron Oliversen to define the schedule
for upcoming data releases, particularly those to go public within the next
few months. This list will be publicized soon (e.g. via the newsletter).
In order to receive EUVE archival GO data sets, interested parties will
be required to register their order with the Archive group in order to help
us track data distribution. The primary mechanism for registration and or-
der of data sets will be via Mosaic; order forms are currently under de-
velopment.
As a final reminder, thirteen full GO data sets have already been pub-
licly released. These observations are listed in the following table; the
Notes column indicates whether the observations are available on 8mm tape
(TAR format) and/or on CD-ROM (see section 6.1 below for ordering instruc-
tions):
Target Observation Exposure
Name Dates Time Notes
------------ -------------- -------- ---------
AT Mic 01-03 Jul 1992 ~39 ksec tape/cdrom1.1
AU Mic 14-17 Jul 1992 ~80 ksec tape
Capella 10-13 Dec 1992 ~80 ksec tape/cdrom2.1b
Feige 24 18-20 Nov 1992 ~58 ksec tape/cdrom2.1a
G191-B2B 13-15 Dec 1992 ~49 ksec tape/cdrom2.1a
HR1099 22-25 Oct 1992 ~79 ksec tape/cdrom2.1c
Moon 10 Dec 1992 ~1.7 ksec tape/cdrom2.1c
PKS2155-304 21-22 Jul 1992 ~35 ksec tape/cdrom2.1c
Procyon 11-15 Jan 1993 ~80 ksec tape/cdrom2.1b
RE1938-461 08-09 Jul 1992 ~39 ksec tape/cdrom2.1c
WD0549+158 10-11 Jan 1993 ~49 ksec tape/cdrom2.1a
WD1620-391 23-25 Jun 1992 ~39 ksec tape/cdrom2.1c
WD1845+019 28-29 Jun 1992 ~39 ksec tape/cdrom2.1a
2. EUVE User's Committee Meeting Notes
======================================
2.1 Next User's Committee Meeting
---------------------------------
by Anne Miller, EGO Technical Writer
The next meeting of the EUVE User's Committee will be held in early May
at NASA's Goddard Space Flight Center (GSFC). The User's Committee is the
liaison between the astronomical community and NASA. A well-focussed sci-
entific program with strong community support will be vital to any contin-
uation or extension of the EUVE mission. If you have input or would like
more information, please contact the User Committee Chairman, Dr. Harry
Shipman, at harrys@strauss.udel.edu (Tel: 302-831-2986) or Deputy Project
Scientist Dr. Ron Oliversen at oliversen@stars.span.nasa.gov (Tel:
301-286-6290).
2.2 Summary of EUVE User's Committee Meeting at Recent AAS
----------------------------------------------------------
by Dr. Harry Shipman, EUVE User's Committee Chairman
The EUVE project attracted considerable attention at the January, 1994
meeting of the American Astronomical Society (AAS) in Washington, D.C.
As you may recall, we presented our EUVE extended mission plans during a
lunch-time meeting for anyone interested. In retrospect, we scheduled a
meeting room which was far too small; crowds overflowed out into the hall
and beyond as hundreds of astronomers were eagerly interested in our plans!
EUVE users have presented over a dozen worthwhile candidate key projects
for an extended mission, and some choices will have to be made; if EUVE
were to do all of these key projects and nothing else, NASA would have to
keep the spacecraft operating for ten years! And at the moment, we do
visualize that a considerable part of an extended mission -- perhaps half
-- will be devoted to smaller GO science projects. The current GO program
has produced a large number of good results in the short time since its
inception, and I think that most of us don't want key projects to com-
pletely shut out GO science.
3. Abstracts of Recently *Accepted* EUVE Papers
===============================================
Included below are abstracts of EUVE-related papers recently *accepted*
for publication in refereed journals. GOs are encouraged to contribute
*accepted* abstracts for inclusion in future editions of this newsletter
and for posting under the EGO Center Mosaic "Home Page". All abstracts
should be sent to egoinfo@cea.berkeley.edu.
--------------------------------------------------------------
LIMITS ON THE HYDROGEN LAYER MASS AND CONSEQUENT HELIUM OPACITY IN HOT DA
WHITE DWARF ATMOSPHERES
M.A. Barstow (U of Leicester), J.B. Holberg (U of AZ) and D. Koester
(U at Kiel, FRG)
to be published in Monthly Notices of the Royal Astronomical Society
The results of the ROSAT sky survey of hot H-rich DA white dwarfs
demonstrated that, at temperatures above ~40,000 K, most stars contain
significant quantities of heavy elements in their atmospheres. Conversely,
below 40,000K most DA white dwarfs appear to have pure H envelopes with,
at most, only small traces of any other material. However, ROSAT was
unable to exclude a contribution from He to the total photospheric opacity
present in these stars. Consequently, the role of He in hot DA white
dwarfs remains uncertain. New spectroscopic observations made by the
Extreme Ultraviolet Explorer (EUVE) satellite promise to provide direct
evidence through a search for photospheric He absorption features. We
have analyzed four well exposed spectra from the EUVE public archive,
finding no evidence for any photospheric He. Using a grid of stratified
model atmospheres we are able to determine lower limits to the mass of
the outer H layer, which are significantly larger than those derived from
earlier broad band results.
--------------------------------------------------------------
THE DISTRIBUTION OF NEUTRAL HYDROGEN IN THE INTERSTELLAR MEDIUM.
I. THE DATA.
A. Fruscione, I. Hawkins, P. Jelinsky, and A. Wiercigroch (CEA)
to be published in The Astrophysical Journal Supplement Series
We compile, from the existing literature, the largest sample to date
(842 data points) of hydrogen column density measurements, N(HI), of the
gas in the interstellar medium. We include only results obtained from ab-
sorption measurements toward individual stars (594 in our sample), in an
effort to construct a three-dimensional picture of the interstellar gas.
We derive hydrogen column densities toward a fraction of the stars in the
sample from published column density measurements of metal ions. A three-
dimensional physical model derived from this data set will be presented in
a companion paper. The observed stars span distances from a few parsecs
to a few thousand parsecs, and more than half of the sample serves to de-
scribe the local interstellar medium within a few hundred parsecs of the
Sun. Hydrogen column densities range from 1e17-1e22 cm^(-2). We describe
here the various observational methods used to estimate the hydrogen col-
umn densities and present the table with the stellar and hydrogen column
density data. The provided table is intended as a global reference work,
not to introduce new results.
Subject headings: interstellar: abundances -- interstellar: matter --
astronomical databases -- catalogs
--------------------------------------------------------------
IONIZATION NEBULAE SURROUNDING SUPER-SOFT X-RAY SOURCES
S. Rappaport, E. Chiang (MIT), T. Kallman (NASA/GSFC), and R. Malina (CEA)
to be published in the Astrophysical Journal
In this work we carry out a theoretical investigation of a new type of
astrophysical gaseous nebula, viz, ionized regions surrounding super-soft
X-ray sources. Super-soft X-ray sources, many of which have characteristic
luminosities of 1e37-1e38 ergs/s and effective temperatures of ~4e5 K,
were first discovered with the Einstein Observatory. These sources have
now been shown to constitute a distinct class of X-ray source, and are be-
ing found in substantial numbers with ROSAT. We predict that these sources
should be surrounded by regions of ionized hydrogen and helium with proper-
ties that are distinct from other astrophysical gaseous nebulae. We pres-
ent calculations of the ionization structure and temperature profiles of
these ionization regions, as well as the expected optical line fluxes.
The ionization profiles for both hydrogen and helium exhibit substantially
more gradual transitions from the ionized to the unionized state than is
the case for conventional HII regions. The calculated optical line inten-
sities are presented as absolute fluxes from sources in the Large Magel-
lanic Cloud and as fractions of the central source luminosity. We find,
in particular, that [OIII] lambda-5008 and HeII lambda-4686 are especially
prominent in these ionization nebulae as compared to other astrophysical
nebulae. We propose that searches for super-soft X-rays via their charac-
teristic optical lines may reveal sources in regions where the soft X-rays
are nearly completely absorbed by the interstellar medium.
--------------------------------------------------------------
4. EUVE Session at the RAS/EAS94 Meeting
========================================
by Mihalis Mathioudakis, CEA Scientist
For those planning to attend the 1994 meeting of the Royal/European
Astronomical Society (RAS/EAS94) in Edinburgh, UK on 5-8 April 1994, you
should know that there will be a 1-hour session on EUVE. We will review
the most recent results from the mission and discuss future opportunities
available for GOs. The session is currently planned for Friday, 8th April
at 13:00; an abstract is available on request. For further details, please
contact:
Mihalis Mathioudakis mihalis@cea.berkeley.edu
Richard Lieu lieu@cea.berkeley.edu
5. "Space News" Highlights EUVE Innovation in Science Operations
================================================================
by Dr. Roger Malina, EUVE Principal Investigator
The 21-27 February issue of "Space News" carries an article (p. 10) by
Debra Werner titled "Artificial Intelligence Eyed to Cut the Cost of Satel-
lite Operations" which describes the efforts underway on EUVE. NASA Code C
has funded the first year of a multi-year program to introduce new software
technology into the EUVE Science Operations Center. This new software will
allow EUVE to move from 3-shift around-the-clock human-tended operations
to a single such shift with the other two being operated autonomously.
This will lead to a significant reduction in operations cost; the hope is
that these techniques will also lead to a corresponding reduction in the
spacecraft operations. A recent report from GSFC (directed by Ron Polidan)
outlines the plan to not only reduce EUVE operations costs significantly,
but to have EUVE serve as a test-bed for techniques that can be applied on
other missions.
6. SOMOWG Meeting Notes
=======================
by Dr. Carol Christian, EGO/Archive Science Manager & SOMOWG Chair
The SOMOWG, the scientific working group that oversees the Mission Op-
erations and Data Analysis aspect of the Astrophysics Division of NASA,
met on 27 January 1994 in Washington D.C. The highlights of the meeting
have been provided on the CEA Mosaic server and are accessible from the
CEA Home Page. Very soon, these notes will be offered through the NASA
Mosaic Home Page.
7. Notes from the EUVE Public Science Archive
=============================================
by Brett A. Stroozas, DASS/Archive Manager
7.1 Reminder on Ordering EUVE CD-ROMs
-------------------------------------
The EUVE Public Science Archive CD-ROM series has been established in
order to more easily distribute the large data sets generated with EUVE
(typically hundreds of megabytes). The initial EUVE CD-ROM -- Volume 1,
Number 1 (Drake, 1993) which was released at the June, 1993 AAS meeting in
Berkeley, CA -- includes a spectrometer observation of the Late-Type star
AT Mic. The second EUVE CD-ROM -- Volume 2, Number 1 A/B/C (Stroozas,
1994) -- was released at the January, 1994 AAS meeting in Washington, D.C.
This set of three CDs contains 11 selected spectrometer calibration obser-
vations, arranged thematically on the various discs: four White Dwarfs on
disc A, two Late-Type stars on disc B and five assorted targets on disc C.
EUVE CD-ROMS may be ordered by electronic or postal mail. To order by
e-mail, send a mail message to archive@cea.berkeley.edu with the words
"mailorder cdromX" (quotes omitted)
as the body of the message (the Subject line is ignored), where "X" is the
CD volume and number (the currently available allowed values for "X" are
"1.1", "2.1a", "2.1b", and "2.1c"). Multiple "mailorder" commands are
allowed in a single mail message. For example, to order both Volume 1,
Number 1 AND Volume 2, Number 1 -- disc A, send the following message:
mail archive@cea.berkeley.edu
Subject:
mailorder cdrom1.1
mailorder cdrom2.1a
In order to control costs and to make sure that requesting parties receive
only the data of interest, we require that each CD be ordered individually;
a request of "mailorder cdrom2.1" will not be processed but will require
that we contact you for further clarification. So, in order to speed up
CD deliveries, and to minimize efforts, please be specific in ordering in-
dividual CDs.
To order CDs via conventional postal mail, send your correspondence to
EUVE Science Archive
Center for EUV Astrophysics
2150 Kittredge Street
University of California
Berkeley, CA 94720
and include the Volume/Number for each CD requested. Again, please be spe-
cific as to which individual CDs you are requesting. All CD orders will be
sent out via postal mail and should arrive within one month (for domestic
orders; international orders will take longer).
7.2 Archive Moving from FTP to Mosaic
-------------------------------------
In order to make EUVE archival material more readily and easily availa-
ble, the Archive is moving all currently available material from the
anonymous ftp site into the Mosaic environment. For those unfamiliar
with this environment, Mosaic provides a very powerful and user-friendly
hyperlink-based interface for browsing, previewing and retrieving infor-
mation across the Internet. For those who currently have the Mosaic
software (available via anonymous ftp from ftp.ncsa.uiuc.edu), the EUVE
Archive may be accessed through the CEA Mosaic "Home Page" URL at
http://cea-ftp.cea.berkeley.edu
Those without windowing capabilities may access this information using the
lynx software. For those having access to neither of these software pack-
ages on their systems, you may run lynx here locally by making a telnet
connection to CEA port #200 (telnet cea-ftp.cea.berkeley.edu 200).
The Archive currently has the following information available on Mosaic:
o data -- survey catalogs (Malina, 1994; Bowyer, 1994) and images; 1-d
spectra
o software -- ISM, EGO Center software and reference data
o documentation -- Archive access information, past issues of this news-
letter, the special EUVE edition of the Journal of the British
Interplanetary Society (JBIS; a good source of general overview
articles), and the EUVE bibliography and papers
This is an on-going process; material is, and will continue to be, added
into the Archive as it becomes available.
7.3 Archive Access Information
------------------------------
Once again, listed below are the various methods for accessing EUVE
archival material:
o CEA WWW Server:
http://cea-ftp.cea.berkeley.edu (Mosaic/lynx remotely)
telnet cea-ftp.cea.berkeley.edu 200 (lynx locally at CEA)
o NASA's ADS: contact ads@cuads.colorado.edu for account information
o CD-ROM Series: Volumes 1 and 2 (four separate CDs) are available
o e-mail: archive@cea.berkeley.edu
(include word "help" -- quotes omitted -- as body of message)
o anonymous FTP (or gopher): cea-ftp.cea.berkeley.edu
o EUVE Electronic Newsletters: ceanews@cea.berkeley.edu (to subscribe)
o Postal Mail:
The EUVE Public Science Archive
Center for EUV Astrophysics
2150 Kittredge St.
Berkeley, CA 94720
510-642-3032 (voice) or 510-643-5660 (fax)
archive@cea.berkeley.edu
8. "egi" Notes for GOs
======================
The following information, originally disseminated on the "egi" mailer
by the EGO Center, contain information useful for GOs (e.g. for data anal-
ysis). The sections included here briefly summarize the original postings
and serve as reminders to the GO community of important events that may
warrant their attention. Any questions or comments should be directed
to the EGO Center (egoinfo@cea.berkeley.edu).
8.1 EGOINFO Update
------------------
by Anne Miller, EGO Technical Writer
All mail to egoinfo@cea.berkeley.edu is now handled by EGO Center staff
and the previously advertised capability to send certain documents auto-
matically has been disabled. All documents are now available via ftp and
telnet at the site mentioned above. In addition, the auto-reply capability
of egoinfo has also been disabled, to avoid unnecessary repeated messages
between the EGO Center and other sites that auto-reply. We repeat that
egoinfo is still the correct address for all electronic questions and cor-
respondence with the EGO Center; staff members will direct your query
to the appropriate person. Users who wish to contact the Center by tele-
phone should call 510-643-5056; your call will be returned promptly.
8.2 Software Release
--------------------
by Anne Miller, EGO Technical Writer
The newest version of the EGO Center data reduction software, EUV1.4,
has been released and is available through the CEA anonymous ftp site in
the /pub/software/euv1.4 directory. The new version includes software
tasks to simulate the effect of interstellar medium (ISM) absorption on
source spectra, and input/output tasks for converting EUVE QPOE files into
FITS format. The software should be used with the recent reference data
release, EGODATA1.8.1, which incorporates the newest and most accurate
wavelength solutions yet available for the EUVE spectrometers; its use
results in more accurate line centers and better correction of spectral
curvature.
EGOCS1.4 has been used for data reduction at the EGO Center since mid-
January; the data on all tapes received by GOs in February have been pro-
cessed with the new wavelength solution. GOs who received their data prior
to this may want to obtain the new software and reference data, rerun the
event pipeline "cep" on their ST tables, and re-extract their spectra.
8.3 Sensitivity Loss at the Boresight Position in the DS
--------------------------------------------------------
by Kelley McDonald and Martin Sirk, DASS Staff Research Associates
On 18 February 1993 at 01:07:04 GMT the Deep Survey instrument (DS)
was pointed at the bright white dwarf HZ43. The intense EUV light from
this star caused a permanent loss in sensitivity at the DS boresight in
a roughly circular region 28 pixels (2.1 arc-minutes) across at FWHM. As
a result, centroid determinations of point sources are subject to system-
atic errors of up to 5 pixels (about 0.4 arc-minutes), and count rates
are affected by as much as 80%.
The problem is believed to be correctable and is being worked upon by
the DASS group at CEA. The current strategy involves building a "flat
field" to correct for the differential sensitivity across the affected
region. If and when a technique is developed, all GOs will be informed
and, if it's requested, given the necessary data to correct the problem.
9. CEA Job Listings
===================
by Cathie Jones, CEA Personnel Manager
Project Manager -- Center for EUV Astrophysics at UC Berkeley, NASA Extreme
Ultraviolet Explorer Project. Oversee all aspects of science operations,
data processing, computer systems and software development. A major focus
will be to implement innovative low cost approaches to science and mission
operations and manage collaborations for development and implementation of
innovative engineering test-beds. Qualifications: Advanced degree in
Physics and/or Astronomy or a related field; or an equivalent combination
of education and experience. Extensive experience with satellite projects
required. Experience with scientific analysis methods and knowledge of
software development preferred. Recent NASA program management experience
preferred. Send resume and names of three references by 31 March 1994,
Cathie Jones/Personnel, Center for EUV Astrophysics, 2150 Kittredge St.,
University of California, Berkeley, CA 94720. EEO/AA.
REFERENCES
==========
o Bowyer, et al., "The First EUVE Source Catalog", Astrophysical Journal
Supplement Series, 1994 (in press)
o Drake, et al., "The Extreme Ultraviolet Explorer Science Archive:
Selected Data and Software", Eds. S. Bowyer and R.F. Malina,
1:1 in the CD-ROM series (ISSN# 1069-7497), 1993
o JBIS, 46(9), September 1993
o Malina, et al., "The Extreme Ultraviolet Explorer Bright Source List",
Astronomical Journal, 1994 (in press)
o Stroozas, et al., "The Extreme Ultraviolet Explorer Science Archive:
Selected Data and Software", Eds. S. Bowyer and R.F. Malina,
2:1 in the CD-ROM series (ISSN# 1069-7497), 1994
---------------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme Ultra-
violet Astrophysics, University of California, Berkeley, CA 94720, USA.
The opinions expressed are those of the authors. EUVE Principal Investi-
gators and Newsletter Publishers: Drs. R.F. Malina and C.S. Bowyer. EGO
and Archive Science Manger: C.A. Christian. Archive Manager and News-
letter Editor: B.A. Stroozas. Funded by NASA contracts NAS5-30180 and
NAS5-29298. Send newsletter correspondence to: ceanews@cea.berkeley.edu.
The EUVE project is managed by NASA's GSFC. The GSFC Project Manager:
Paul Pashby, Project Scientist: Dr. Yoji Kondo, Deputy Project Scientist:
Dr. Ronald Oliversen. NASA HQ Program Scientist: Dr. Robert Stachnik,
Deputy Program Scientist: Dr. D. Buzasi, Program Manager: Dr. G. Riegler.
GSFC Project Operations Director: Mr. Kevin Hartnett. Information on the
EUVE Guest Observer Program is available from: Dr. Y. Kondo, Mail Code
684, GSFC, Greenbelt, MD 20771 at (301) 286-6247 or e-mail to
euve@stars.span.nasa.gov.
END-----------EUVE------------ELECTRONIC---------------NEWS-------------END
% ====== Internet headers and postmarks (see DECWRL::GATEWAY.DOC) ======
% Date: Wed, 9 Mar 1994 12:14:30 -0800
% From: EUVE Electronic Newsletter distribution <ceanews@cea.Berkeley.EDU>
% To: euvenews@cea.Berkeley.EDU
% Subject: EUVE Electronic Newsletter
|
| 770.35 | March 25 | JVERNE::KLAES | Be Here Now | Fri Mar 25 1994 12:44 | 152 |
| From: VERGA::US4RMC::"ceanews@cea.Berkeley.EDU" "EUVE Electronic Newsletter
distribution 25-Mar-1994 0443" 25-MAR-1994 04:38:42.67
To: euvenews@cea.Berkeley.EDU
CC:
Subj: EUVE NEWS FLASH
EEEEEEEEEEE U U V V EEEEEEEEEEE
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ELECTRONIC NEWS ***FLASH*** OF THE EUVE OBSERVATORY
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Vol 4, No. 3a 25 March 1994 ISSN 1065-3597
-------------------------------------------------------------------------------
Public Release of Guest Observer Data in May and June, 1994
===========================================================
by Brett A. Stroozas, Archive Manager
As proprietary data rights for Guest Observer (GO) phase observations begin
to expire in May, 1994, the EUVE Archive group is working to make these data
sets available to the astronomical community. The early results from the EUVE
mission have included many exciting and important scientific discoveries; we
encourage the scientific community to further delve into the archival data as
it becomes available.
The table below lists all observations currently released as well as those
to go public in May and June of 1994. The full data sets will be distributed
on 8mm tape in "tar" format (readable within IRAF); the 1-d FITS spectra only
will be accessible on-line via anonymous ftp (cea-ftp.cea.berkeley.edu).
Due to various scheduling constraints, observations are often carried out
in a series of pointings over a period of weeks or even months. Each entry in
the table below corresponds to an individual non-consecutive pointing. The
columns in the table are as follows:
o Target -- Name of observed target. Target names preceded by "*" were
calibration observations.
o RA/Dec -- Right Ascension and Declination (decimal degrees) of observed
target in J2000 coordinates.
o Exp -- Approximate exposure time in kiloseconds (actual exposure time varies
by spectrometer channel).
o Date -- GMT date on which the science observation was completed (yymmdd).
o Q -- A two-character code used to indicate the quality of the archival data
products. The first character reflects the "level" of the processing
software and reference data (level 2 is currently the best); the second
reflects the care taken during the spectral extraction process ("n" is
for nominal and "o" is optimal). Although all data sets are currently
"1n", the Archive group will (as resources allow) be reprocessing the
observations in the near future. If you don't wish to wait for us to
get to reprocessing your favorite target(s), you are encouraged to order
the data and reprocess it yourself using the EGO Center software and
reference data which is available in the ftp site.
o CD-ROM -- This column indicates which EUVE CD-ROM (if any) on which the
observation is also available.
o DataID -- This is a unique identification code for each observation, composed
of the end date and target name for the observation (DataID codes for
CD-ROMs are listed in the CD-ROM column). The DataID codes must be
used to order full GO data sets on tape or CD-ROM (see below).
------------------------------------------------------------------------------
Target RA Dec Exp Date Q CD-ROM DataID
------------------------------------------------------------------------------
Data Sets Currently Available:
*AT_Mic 310.46100 -32.43900 39 920703 1n cdrom1.1 920703_at_mic
*AU_Mic 311.29000 -31.33400 80 920717 1n -------- 920717_au_mic
*Capella 79.17208 45.99806 75 921213 1n cdrom2.1b 921213_capella
*Feige_24 38.77920 3.73694 58 921120 1n cdrom2.1a 921120_feige_24
*G191-B2B 76.37750 52.83139 49 921215 1n cdrom2.1a 921215_g191-b2b
*HR1099 54.19620 0.59028 74 921025 1n cdrom2.1c 921025_hr1099
*Moon -------- -------- 2 921210 1n cdrom2.1c 921210_moon
*PKS2155-304 329.71800 -30.22300 35 920722 1n cdrom2.1c 920722_pks2155-304
*Procyon 114.82410 5.227500 97 930115 1n cdrom2.1b 930115_procyon
*RE1938-461 294.64833 -46.21589 40 920709 1n cdrom2.1c 920709_re1938-461
*WD0549+158 88.11280 15.89010 60 930111 1n cdrom2.1a 930111_wd0549+158
*WD1620-391 245.89667 -39.22940 32 920625 1n cdrom2.1c 920625_wd1620-391
*WD1845+019 281.91400 1.95900 27 920629 1n cdrom2.1a 920629_wd1845+019
Data Sets Available 1 May 1994:
chi_Ori 88.59542 20.27611 115 930130 1n -------- 930130_chi_ori
*Feige_24 38.77920 3.73694 46 921027 1n -------- 921027_feige_24
*HZ_43 199.09125 29.09917 39 930219 1n -------- 930219_hz_43
*kappa_Sco 265.62100 -39.03000 13 920626 1n -------- 920626_kappa_sco
Mars 104.50000 26.88333 48 930123 1n -------- 930123_mars
*MCT2020-4234 305.99775 -42.40700 39 920719 1n -------- 920719_mct2020-4234
*sigma_Gem 115.82667 28.88333 56 930207 1n -------- 930207_sigma_gem
VV_Pup 123.77833 -19.05489 46 930209 1n -------- 930209_vv_pup
*WD1123+189 171.57958 18.65472 24 930214 1n -------- 930214_wd1123+189
*WD1123+189 171.57958 18.65472 21 930310 1n -------- 930310_wd1123+189
*WD1254+223 194.25958 22.03194 53 930211 1n -------- 930211_wd1254+223
*WD1254+223 194.25958 22.03194 29 930304 1n -------- 930304_wd1254+223
*WD2309+105 348.08958 10.78444 43 920821 1n -------- 920821_wd2309+105
*WD2309+105 348.08958 10.78444 58 920928 1n -------- 920928_wd2309+105
*XI_UMa 169.54542 31.52917 55 930330 1n -------- 930330_xi_uma
Data Sets Available 1 June 1994:
31_Com 192.92417 27.54056 66 930213 1n -------- 930213_31_com
AD_Leo 154.90208 19.87000 90 930303 1n -------- 930303_ad_leo
*alpha_Cen_A 219.90100 -60.83530 75 930601 1n -------- 930601_alpha_cen_a
*alpha_Cen_A 219.90100 -60.83530 30 930608 1n -------- 930608_alpha_cen_a
AN_UMa 166.10750 45.05417 44 930301 1n -------- 930301_an_uma
*AU_Mic 311.29000 -31.33400 47 930723 1n -------- 930723_au_mic
epsilon_CMa 104.65833 -28.97210 62 930118 1n -------- 930118_epsilon_cma
*HR1099 54.19620 0.59028 134 930921 1n -------- 930921_hr1099
Jupiter --------- -------- 65 930401 1n -------- 930401_jupiter
*MCT2153-4156 329.14704 -41.70397 1 930808 1n -------- 930808_mct2153-4156
PSR0656+14 104.95000 14.23917 106 930203 1n -------- 930203_psr0656+14
RE0515+324 78.84875 32.67889 59 930126 1n -------- 930126_re0515+324
RE1027+322 156.79875 32.39000 119 930308 1n -------- 930308_re1027+322
RE1032+532 158.03458 53.48889 60 930205 1n -------- 930205_re1032+532
RE1149+28 177.48208 28.75222 83 930225 1n -------- 930225_re1149+28
*WD1254+223 194.25958 22.03194 25 930406 1n -------- 930406_wd1254+223
*WD1620-391 245.89667 -39.22940 47 930521 1n -------- 930521_wd1620-391
*WD1620-391 245.89667 -39.22940 52 930702 1n -------- 930702_wd1620-391
*WD1845+019 281.91400 1.95900 29 930623 1n -------- 930623_wd1845+019
*WD2309+105 348.08958 10.78444 25 930831 1n -------- 930831_wd2309+105
YZ_CMi 116.17360 3.55542 68 930227 1n -------- 930227_yz_cmi
------------------------------------------------------------------------------
Once again, access to the 1-d FITS format spectra only will be available
on-line via the CEA anonymous ftp site (cea-ftp.cea.berkeley.edu) in the
/pub/archive/spectra directory.
Orders for full GO data sets must contain your name, full postal mailing
address, e-mail address (if any), telephone number (in case we need to contact
you for more information), and DataID(s) for the requested data set(s) as taken
from the list above. Direct all orders via postal or e-mail to:
EUVE Public Science Archive
Center for EUV Astrophysics
2150 Kittredge Street
University of California
Berkeley, CA 94720
510-642-3032 (voice) or 510-643-5660 (fax)
archive@cea.berkeley.edu
For domestic orders, please allow ~4 weeks for delivery (international orders
will take longer). The Archive group will soon provide mechanisms for ordering
data via e-mail and Mosaic; these will be announced as they become available.
% ====== Internet headers and postmarks (see DECWRL::GATEWAY.DOC) ======
% Date: Fri, 25 Mar 1994 00:21:47 -0800
% From: EUVE Electronic Newsletter distribution <ceanews@cea.Berkeley.EDU>
% To: euvenews@cea.Berkeley.EDU
% Subject: EUVE NEWS FLASH
|
| 770.36 | EUVE Newsletter -- 12 April 1994 | CXDOCS::J_BUTLER | E pur, si muove... | Thu Apr 14 1994 13:58 | 618 |
| From: ceanews@imperial.cea.berkeley.edu
(EUVE Electronic Newsletter distribution)
Newsgroups: sci.space.news
Subject: EUVE Electronic Newsletter
Date: 14 Apr 1994 05:53:49 -0700
Organization: Center For Extreme Ultraviolet Astrophysics
Sender: daemon@news.arc.nasa.gov
EEEEEEEEEEE U U V V EEEEEEEEEEE
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
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Vol 4, No. 4 12 April 1994 ISSN 1065-3597
---------------------------------------------------------------------------
Notes from the Editor
=====================
by Brett A. Stroozas, Data Analysis Support Staff (DASS)
and Archive Manager
Welcome to the electronic newsletter for NASA's Extreme Ultraviolet Explorer
satellite (EUVE), which is compiled and published monthly by the EUVE Public
Science Archive group at the Center for EUV Astrophysics (CEA) in Berkeley,
CA. The EUVE observatory continued to perform extremely well throughout the
month of March, completing observations of the following Guest Observer (GO)
targets: Epsilon and Beta CMa, G191-B2B, Procyon, Vela SNR, Jupiter,
RE0623-374, HZ43, Moon, Alpha, and Beta Cen. There were also brief pointed-
and survey-mode observations during the month for the purposes of trending and
calibrating the satellite's star trackers and sun sensors. EUVE reached a
major milestone on Sunday, 27 March, completing its 10,000th orbit!
The contents of this issue of the EUVE electronic newsletter are as follows:
1. Next EUVE User's Committee Meeting
2. May/June Releases of GO Archival Data
3. The Beta Cen Mystery: Evidence for Recent Degradation of the Al/Ti/C
Filter of Scanner A
4. First Hardware Failure on EUVE
5. Notes from the EUVE Guest Observer Center
6. Notes from the EUVE Public Science Archive
7. Abstracts of Recently *Accepted* EUVE Papers
8. CEA Job Listings
To comment on, make suggestions for, or request subscriptions to the EUVE
electronic newsletter, send e-mail to ceanews@cea.berkeley.edu (Internet).
1. Next EUVE User's Committee Meeting
=====================================
by Dr. Ron Oliversen, Deputy Project Scientist at GSFC
The EUVE User's Committee will meet at Goddard Space Flight Center (GSFC)
on 12 and 13 May. If there are any issues and/or concerns you wish to have
discussed, please contact any of the Committee members (listed below) or the
Project Science Office.
Name e-mail Institution
---------------------- -------------------------------- ------------------
Shipman, Harry (Chair) harrys@strauss.udel.edu U Delaware
Brown, Alex ab@jila.colorado.edu U Colorado
Bruhweiler, Fred bruhweiler@iue.dnet.nasa.gov Catholic U
Cassinelli, Joe cassinelli@madraf.astro.wisc.edu U Wisconsin
Doschek, George doschek@11334.dnet.nasa.gov Naval Research Lab
Dupree, Andrea dupree@cfa.harvard.edu SAO/CfA
Hall, Doyle dthall@pha.jhu.edu Johns Hopkins U
Holberg, Jay holberg@looney.lpl.arizona.edu U Arizona/LPL
Howell, Steve howell@frankenstein.psi.edu Planetary Sci Inst
Judge, Phil judge@hao.ucar.edu HAO/NCAR
Liebert, Jim liebert@as.arizona.edu U Arizona
Nousek, John nousek@astro.psu.edu Penn State U
Polidan, Ron polidan@aesop.gsfc.nasa.gov NASA/GSFC
2. May/June Releases of GO Archival Data
========================================
by Brett Stroozas, DASS/Archive Manager
Beginning on 1 May, proprietary data rights for GO observations begin to
expire. The table below lists those pointings which will go public in May and
June. This list is identical to that which was distributed in the recent news
"flash" (V4#3a, 25 March) except for the following changes:
o HR1099, a calibration and GO target, has been pulled from the release list.
Calibration observations may, in general, be released earlier than the one
year proprietary period. In the case of HR1099, the GO had been awarded
time in addition to that requested for calibration purposes and, therefore,
warrants additional time for the analysis of this observation.
o The February, 1993 observation of WD1254+223 will be released on 1 June
(instead of 1 May), in line with the one-year proprietary period.
The table below lists a total of 38 pointings to be released, 14 in May and 24
in June. Each entry corresponds to the data for one continuous observation
pointing, typically stored on one 8mm tape. The columns in the table below
are as follows:
o Name -- Name of target. Those names preceded by "*" were also calibration
pointings in the Lex/B filter (on or near boresight); those with "x" were
used for calibrating the Al/C filter (far off boresight).
o Exp -- Approximate exposure time in ksec (actual exposure varies by
spectrometer channel).
o RA -- Target Right Ascension (J2000) in decimal degrees.
o DEC -- Target Declination (J2000) in decimal degrees.
o Q -- Flag indicating the quality of the science data products (see below).
o DataID -- Unique identification code assigned to each pointing. These codes
should be used when ordering data sets.
------------------------------------------------------------------
Name Exp RA DEC Q DataID
------------------------------------------------------------------
Data Sets Available 1 May 1994:
CHI_ORI 115 88.59542 20.27611 1n 930130_chi_ori
* FEIGE24 46 38.77920 3.73694 1n 921027_feige_24
* HZ43 40 199.09125 29.09917 2o 930219_hz_43
* KAPPA_SCO 15 265.62100 -39.03000 1n 920626_kappa_sco
MARS 50 104.50000 26.88333 1n 930123_mars
* MCT2020-4234 40 305.99775 -42.40700 1n 920719_mct2020-4234
* SIGMA_GEM 55 115.82667 28.88333 2o 930207_sigma_gem
VV_PUP 45 123.77833 -19.05489 1n 930209_vv_pup
* WD1123+189 24 171.57958 18.65472 1n 930214_wd1123+189
* WD1123+189 20 171.57958 18.65472 1n 930310_wd1123+189
* WD1254+223 29 194.25958 22.03194 1n 930304_wd1254+223
* WD2309+105 43 348.08958 10.78444 1n 920821_wd2309+105
* WD2309+105 55 348.08958 10.78444 2o 920928_wd2309+105
* XI_UMA 55 169.54542 31.52917 1n 930330_xi_uma
Data Sets Available 1 June 1994:
31_COM 73 192.92417 27.54056 1n 930213_31_com
AD_LEO 90 154.90208 19.87000 2o 930303_ad_leo
* ALPHA_CEN_A 55 219.90100 -60.83530 2o 930531_alpha_cen_a
* ALPHA_CEN_A 27 219.90100 -60.83530 1n 930601_alpha_cen_a
* ALPHA_CEN_A 30 219.90100 -60.83530 1n 930608_alpha_cen_a
AN_UMA 44 166.10750 45.05417 2o 930301_an_uma
* AU_MIC 55 311.29000 -31.33400 1n 930723_au_mic
EPSILON_CMA 65 104.65833 -28.97210 2o 930118_epsilon_cma
JUPITER 65 0.00000 0.00000 2o 930401_jupiter
* MCT2153-4156 2 329.14704 -41.70397 1n 930808_mct2153-4156
PSR0656+14 106 104.95000 14.23917 1n 930203_psr0656+14
RE0515+324 60 78.84875 32.67889 1n 930126_re0515+324
RE1027+322 120 156.79875 32.39000 1n 930308_re1027+322
RE1032+532 60 158.03458 53.48889 1n 930205_re1032+532
RE1149+28 83 177.48208 28.75222 1n 930225_re1149+28
WD1254+223 55 194.25958 22.03194 2o 930211_wd1254+223
* WD1254+223 31 194.25958 22.03194 1n 930406_wd1254+223
* WD1620-391 51 245.89667 -39.22940 1n 930521_wd1620-391
* WD1620-391 54 245.89667 -39.22940 1n 930702_wd1620-391
x WD1620-391 3 245.89667 -39.22940 1n 930702x_wd1620-391
x WD1845+019 1 281.91400 1.95900 1n 930616x_wd1845+019
* WD1845+019 32 281.91400 1.95900 1n 930623_wd1845+019
* WD2309+105 30 348.08958 10.78444 1n 930831_wd2309+105
YZ_CMI 85 116.17360 3.55542 1n 930227_yz_cmi
------------------------------------------------------------------
As indicated above, the "Q" flag is used to give researchers a rough indica-
tion of the quality of the science data products (e.g. the extracted spectra).
Codes are in the form "Nx" where "N" reflects the quality of the processing
software and/or reference data (higher N values are best) and "x" the level of
human interaction -- nominal (n) or optimal (o) -- during the spectral reduction
process (optimal extraction is best as it was done much more carefully). A "2o"
data set is of the current top-of-the-line quality; "2o" is of higher quality
than "2n" which, in turn, is of higher quality than "1o", etc.
Researchers should note that the delivered data sets include the complete
telemetry tables for the observation of interest. By retrieving the most
up-to-date versions of the EGO Center software and reference data from the CEA
anonymous ftp site, the researcher has all that is necessary to reprocess the
data and do the best possible job at the spectral extraction. So, a "1n" coded
data set from the list above is fully complete but will require more work on
the part of the researcher in its analysis. The Archive will (as resources
allow) reprocess the archival data sets as a convenience to the community.
The community is encouraged to order these data sets by sending an e-mail
request to archive@cea.berkeley.edu including your name, mailing address,
telephone number, and the "DataID" code(s) from the table above. Data sets
will be distributed on 8mm tape via postal mail and should arrive within 4
weeks. New sets of observations will go public every month thereafter, lists
of which will be published (e.g. in this newsletter) at least one month in
advance. Mechanisms for previewing and ordering data sets via Mosaic are under
development.
3. The Beta Cen Mystery: Evidence for Recent Degradation
of the Al/Ti/C Filter of Scanner A
=========================================================
by Dr. John Vallerga, CEA Scientist
During a GO observation of HZ43 in the Deep Survey/Spectrometer (DS/S) on
Saturday, 26 March at 03:25 PST, the EUVE payload controllers noticed a bright
source in the Scanner A Al/Ti/C filter quadrant. During that day it was
determined that for this Right-Angle Program (RAP; so-called because the
Scanners observe at 90 degrees to the DS/S) source the count rate when
unobstructed by the filter bar was ~22 counts/second (cps) in Al/Ti/C (Scanner
A), ~1 cps in the Lex/B (Scanner B) and ~2 cps in the "Dagwood" (Scanner C).
Since EUVE was dithering on the GO target, the stellar image moved around the
detector and filter, proving that it was not a "hot spot" or filter pinhole.
It was determined that the position of the source was within a few arc minutes
of beta Centaurus, a bright (m_v = 0.6) B1III star at a distance of 89 parsecs.
Because it was a B star, we immediately considered the possibility of an
ultraviolet (UV) leak, and the Lex/B count rate was consistent with a UV leak
of a star of this magnitude. However, the Al/Ti/C and Dagwood filters did not
have a UV leak during the all-sky survey since NO B stars were detected in
either of these (except for the EUV flux from beta and epsilon Canis Majoris).
A Target of Opportunity was requested to point the DS/S at beta Cen. The
Scanner observation of beta Cen was stopped at 4:08 (PST) on Sunday, 27 March
when the EUVE DS/S slewed to the Moon; at 13:20 PST, EUVE slewed to beta Cen.
The initial detector plots revealed no bright EUV spectrum! When EUVE slewed
back to HZ43 at 10:40 PST on Monday, 28 March, the spacecraft roll angle was
different so beta Cen was not in the field-of-view (FOV) of the Scanners. A
Target Adjustment Request (TAR) was made to change the spacecraft roll and
return beta Cen to the Scanner A Al/Ti/C FOV and the bright source reappeared!
Another TAR moved the source to the Al/Ti/C filter of Scanner B and the source
was not detected. The ratio of the beta Cen count rates between the Scanner A
and B Al/Ti/C filters was a factor of > 3000, indicating that the beta Cen
detection was an out-of-band leak in Scanner A and not a variable source.
The cause of this leak and the time it first occurred are not presently
known. We are certain that the filter UV throughput was low during the survey
phase of the mission and for some time afterwards based on the non-detections
of bright B stars in this filter. We are currently checking more recent data
for B star detections and will soon be performing calibration pointings at UV
and far-UV (FUV) sources (e.g. the Moon, B and A stars) to characterize the
spectral nature of the leak. We also have test filters in storage that will be
checked for physical degradation and transmission changes. There is no evidence
that any change has occurred to the Spectrometer or Deep Survey filters; how-
ever, any unexplained throughput change in orbit is a concern and we will do
our best to find the cause of the one in Scanner A.
Previous observations of B stars during the all-sky survey and RAP did not
detect even the brightest ones (e.g. alpha Vir and alpha Eri) in this filter
bandpass. The fact that the throughput increase was greater than three orders
of magnitude implies that the wavelength region which changed was one of low
throughput to begin with. The region is not in the soft x-ray, as there the
filter is already mostly transparent and the detector has a high quantum
efficiency (QE). In the soft x-ray the telescope is the component that limits
the throughput and it is very unlikely for the telescope to increase its
reflection efficiency by three orders of magnitude.
Somehow the filter/detector developed an FUV or UV leak. The UV leak (2500
A) is unlikely since the count rate in the Al/Ti/C filter was a factor of 20
greater than that in the Lex/B filter, which is already transparent to UV at
this wavelength. That leaves the FUV (>912 A). If the filter has a grey
spectral response, then the throughput will be highest at 912 A since the QE of
the detector is falling like a power law with wavelength. A transmission of
1e-6 is roughly what it would take to see the count rate observed for beta Cen.
But to achieve that transmission would require the complete removal of either
the aluminum or the carbon from the Al/Ti/C filter. Maybe the atomic oxygen in
orbit has managed to oxidize the carbon in the filter, but then we would have
to explain why we don't detect the 584 A geocoronal flux. A collection of very
small pinholes that result in a grey transmission of 1e-6 would result in the
900 A FUV response whose shape is determined by the MgF_2 QE curve and yet not
increase the geocoronal backgrounds. A good test of this would be to observe
the Moon.
4. First Hardware Failure on EUVE
=================================
by Kevin Hartnett, GSFC Project Operations Director
The EUVE spacecraft suffered its first true hardware failure on the afternoon
of Saturday, 2 April during orbit 10,093 with the loss of its "B" side
transmitter. Configured to the high gain antenna (HGA) since shortly after
launch, transmitter "B" -- the return link side of EUVE's second generation
Tracking and Data Relay Satellite (TDRS) transponder "B" -- showed no overt
signs of anomalous performance during its previous two successful uses (a tape
recorder dump and a real-time pass) just hours earlier, but failed to radiate
during a pass scheduled at 18:26 GMT resulting in a negative acquisition by the
TDRS Space Network (SN). Over a period of approximately 12 hours, members of
the Loral Flight Operations Team -- later augmented by engineering
representatives from NASA, Jackson & Tull and Fairchild Space -- determined the
likely occurrence had been the failure of the power amplifier stage in the "B"
transmitter, and reviewed the procedures necessary to switch transponder "A"
(normally configured to the omni antennas) to the HGA. Emergency ground
contacts with Deep SN Madrid and GN Mila were arranged along with numerous omni
SN events to allow for the orderly execution of the plans which culminated in
the switchover during overlapping Mila and TDRS supports at approximately 07:00
GMT on Easter Sunday. Because of the combined 16 hour record capacity of EUVE's
two tape recorders, and their careful management by the Flight Controllers, no
science data was lost during the incident. Subsequent TDRS passes throughout
the day on Sunday were nominal, with HGA commands executing from stored command
loads which had been regenerated overnight. Transponder "A" will remain
configured to the HGA with the transmitter on. This is judged to be the most
prudent operational approach until thorough analysis of the engineering
housekeeping data recorded during the failure is accomplished.
Accolades, congratulation and thanks is due to all the EUVE team who
sacrificed their sleep and Easter morning plans to support the anomaly
investigation and restoration of HGA communications. The planning, execution
and conduct of those involved, including the GSFC and JPL institutional support
elements, were exemplary in every respect.
5. Notes from the EUVE Guest Observer (EGO) Center
==================================================
by Anne Miller, EGO Technical Writer
5.1 Cycle III NRA Slated for Release in May
-------------------------------------------
The the NASA Research Announcement (NRA) to cover the third and, possibly,
last observing year of the EGO program is scheduled to be released in May, 1994.
The following *tentative* schedule has been put forward for the proposal cycle
(dates are subject to change):
15 May, 1994 release of the NRA
15 Aug, 1994 proposals due
Oct, 1994 peer review of proposals
Feb, 1995 beginning of funding and GO observations
Observations in Cycle III will no longer be limited to spectrometer
pointings; researchers will be able to apply for data from the Deep Survey and
Scanning telescope detectors, although some restrictions will apply. In
addition, the NRA will encourage proposals for more extended programs of
research, which will observe five or more sources and require large time
commitments, to focus on particularly challenging astrophysical problems.
Final details of these policies will be included in the NRA.
Researchers who wish to be receive the NRA may ensure their inclusion on the
mailing list by contacting:
Dr. Yoji Kondo, EUVE Project Scientist
Code 684
Building 21, Room G 59
Goddard Space Flight Center
National Aeronautics and Space Administration
Greenbelt, MD 20711 USA
Telephone: (301) 286-7664
euve@stars.gsfc.nasa.gov (Internet)
If you have access to Mosaic, you may also use the Registration service,
described in the next section.
5.2 EGO Center HomePage in Mosaic
---------------------------------
The EGO Center at CEA supports a number of services on the World Wide Web in
Mosaic. The EGO Center may be accessed via the Uniform Resource Locator (URL)
for the CEA "HomePage":
http://cea-ftp.cea.berkeley.edu
The EGO Center provides the user with access to the following information and
programs:
>> What's New: Announcements from the EGO Center.
>> Registration: Registers a subscription for you to the EUVE Electronic
Newsletter. Also signs you up to receive information about the next
NRA.
>> Proposal Database: Information on Cycle I proposals.
>> Target Visibility: Given position and exposure this server will generate
a suitability plot, which describes how well EUVE can observe the target
on any given day for a period of one year.
>> ISM Server: Executes ISM modeling code with user's parameters.
>> EUVE BSL Interactive Skymap: Find EUVE Bright Source List objects on the
sky.
>> EGO Abstracts: Abstracts of GO papers.
The CEA/EUVE anonymous ftp site, which contains public data and archives, may
also be accessed from the CEA HomePage. Those who would like to browse the CEA
ftp site in this manner, but who do not have access to Mosaic, may log in with
telnet and use lynx, a menu-driven program that searches, displays, and
retrieves copies of files. To use lynx, type:
% telnet ftp.cea.berkeley.edu 200
Look for announcements and NRA material in the ftp site later this year.
6. Notes from the EUVE Public Science Archive
=============================================
by Brett A. Stroozas, DASS/Archive Manager
6.1 ISM Server in ADS
---------------------
The EUVE ISM software is used to correct for source flux attenuation at EUV
wavelengths due to the intervening interstellar medium (ISM; based on a model
by Rumph, Bowyer and Vennes). This software, which has been available for some
time in the Archive section of the CEA ftp site, is now available as a service
to users of NASA's Astrophysics Data System (ADS). This service, available
under the ADS "Tools" menu, prompts the user for various input parameters and
a file of unattenuated source flux vs. wavelength. The output is an ADS table
which, using the ADS table editing tools, may be manipulated at will by the
user. We encourage researchers to use this service and send us any comments
and/or suggestions.
6.2 Archive Access Information
------------------------------
Once again, listed below are the various methods for accessing EUVE archival
material:
o CEA WWW Server:
http://cea-ftp.cea.berkeley.edu (Mosaic/lynx remotely)
telnet cea-ftp.cea.berkeley.edu 200 (lynx locally at CEA)
o NASA's ADS (general and account information):
http://adswww.colorado.edu/adswww/adshomepg.html (Mosaic/lynx)
ads@cuads.colorado.edu
o CD-ROM Series: Volumes 1.1 and 2.1 (four separate CDs) are available
o e-mail: archive@cea.berkeley.edu
(include word "help" -- quotes omitted -- as body of message)
o anonymous FTP (or gopher): cea-ftp.cea.berkeley.edu
o EUVE Electronic Newsletters: ceanews@cea.berkeley.edu (to subscribe)
o Postal Mail:
The EUVE Public Science Archive
Center for EUV Astrophysics
2150 Kittredge St.
Berkeley, CA 94720
510-642-3032 (voice) or 510-643-5660 (fax)
archive@cea.berkeley.edu
7. Abstracts of Recently *Accepted* EUVE Papers
===============================================
Included below are abstracts of EUVE-related papers recently *accepted* for
publication. GOs are encouraged to contribute *accepted* abstracts for inclu-
sion in future editions of this newsletter and for posting under the EGO Center
Mosaic "Home Page". All abstracts should be sent to egoinfo@cea.berkeley.edu.
For those papers authored by CEA scientists, the EUVE publication number is
indicated. Researchers may obtain (p)reprints of these papers by sending an
e-mail request along with the publication number(s) of interest to
pub@cea.berkeley.edu.
--------------------------------------------------------------
LIMITS ON THE HYDROGEN LAYER MASS AND CONSEQUENT HELIUM OPACITY IN HOT DA
WHITE DWARF ATMOSPHERES
M.A. Barstow (U. Leicester, UK), J.B. Holberg (U. AZ) and D. Koester
(ITPS-Kiel, FRG)
to appear in Monthly Notices of the Royal Astronomical Society
The results of the ROSAT sky survey of hot H-rich DA white dwarfs
demonstrated that, at temperatures above ~40,000 K, most stars contain
significant quantities of heavy elements in their atmospheres. Conversely,
below 40,000 K most DA white dwarfs appear to have pure H envelopes with,
at most, only small traces of any other material. However, ROSAT was unable
to exclude a contribution from He to the total photospheric opacity present
in these stars. Consequently, the role of He in hot DA white dwarfs remains
uncertain. New spectroscopic observations made by the Extreme Ultraviolet
Explorer (EUVE) satellite promise to provide direct evidence through a search
for photospheric He absorption features. We have analyzed four well exposed
spectra from the EUVE public archive, finding no evidence for any photospheric
He. Using a grid of stratified model atmospheres we are able to determine
lower limits to the mass of the outer H layer, which are significantly larger
than those derived from earlier broad band results.
--------------------------------------------------------------
EXTREME ULTRAVIOLET EXPLORER SATELLITE OBSERVATION OF JUPITER'S IO PLASMA TORUS
D.T. Hall (JHU), G.R. Gladstone (SRI), H.W. Moos (JHU), F. Bagnel, J.T. Clark,
M.A. McGrath, N.M. Schneider, D.E. Shemansky, D.F. Strobel, and J.H. Waite
to appear in Astrophysical Journal Letters
We present the first Extreme Ultraviolet Explorer satellite observation of
the Jupiter system, obtained during the two day period 1993 March 30 through
April 1, which shows a rich emission line spectrum from the Io plasma torus
spanning wavelengths 370 to 735 A. The emission features correspond primarily
to known multiplets of oxygen and sulfur ions, but a blended feature near 372 A
is a plausible NaII transition. The summed detected energy flux of (7.2 +/-
0.2)e-11 erg cm^(-2) s^(-1) corresponds to a radiated power of approximately
4e11 Watts in this spectral range. All ansa emissions show a distinct dawn-dusk
brightness asymmetry and the measured dusk/dawn ratio of the bright SIII 680 A
feature is 2.3 +/- 0.3, significantly larger than the ratio measured by the
Voyager spacecraft UV instruments. A preliminary estimate of ion partitioning
indicates that the oxygen/sulfur ion ratio is approximately 2, compared to the
value approximately 1.3 measured by Voyager, and that [NaII]/[e] > 0.01.
--------------------------------------------------------------
EUVE SPECTROSCOPY OF XI UMA, SIGMA GEM, AND CHI^1 ORI
R. Mewe, C.J. Schrijver (SRON-Utrecht), J.S. Kaastra (SRON-Leiden), F.J.M.
Alkemade (SRON-Utrecht), and B.M. Haisch (CEA/Lockheed)
to appear in "Proc. Eighth Cambridge Workshop on Cool Stars, Stellar Systems,
and the Sun", ed. J.P. Caillault, ASP Conf. Series, 1994, in press.
The analysis of the EXOSAT Transmission Grating Spectrometer (TGS) (10-200 A)
spectra of two RS-CVn systems, Capella and sigma^2 CrB, as presented by Lemen
et al. (1989), showed the coronae of these stars to be dominated by emission
from two temperature intervals, one around solar coronal temperatures, the other
in excess of 10 MK. The lack of strong emission from plasma at < 1 MK was shown
to be consistent with models of quasi-static loops that were narrower at the
footpoints than at the tops (Schrijver et al. 1989). Recent high-resolution
observations by YOHKOH suggest, however, that the solar coronal loops do not
have such a strongly changing cross section with height, at least for plasma
above ~1 MK. We observed other cool stars (the RS CVn's xi Uma, sigma Gem, and
the single MS star chi^1 Ori) with the EUVE spectrometers to study the
temperature structure of stellar coronae and the geometry of coronal loops.
Here we report preliminary results of a differential emission measure analysis.
--------------------------------------------------------------
DETECTION OF EUV EMISSION FROM THE LOW ACTIVITY DWARF HD 4628: EVIDENCE FOR
A COOL CORONA
M. Mathioudakis, J.J. Drake (CEA), P.W. Vedder (CEA/NASA), J.H.M.M. Schmitt
(MPIE), and S. Bowyer (CEA)
to appear in Astron. & Astrophys.
[CEA publication #580]
We present observations of low activity late-type stars obtained with the
Extreme Ultraviolet Explorer (EUVE). These stars are the slowest rotators, and
acoustic heating may dominate their outer atmospheric heating process. We report
detection of EUV emission from the low activity K dwarf HD 4628 during the EUVE
Deep Survey in the Lexan/boron band. This detection, in conjunction with the
non-detection of this object in the ROSAT PSPC all-sky survey, suggests the
existence of a cool corona with a characteristic temperature of less than
1e6 K. The flux and spectral signature are consistent with current theories
of acoustic heating.
Keywords: coronal heating -- late-type stars -- extreme ultraviolet
--------------------------------------------------------------
8. CEA Job Listings
===================
by Cathie Jones, CEA Personnel Manager
Postgraduate/Assistant Research (depending on experience)
University of California
Center for EUV Astrophysics
Attn: Cathie Jones/Personnel
2150 Kittredge St.
Berkeley, CA 94720
The Extreme Ultraviolet Explorer (EUVE) Program at the Center for EUV
Astrophysics, of the University of California, Berkeley, has opening for a
Research Scientist. Successful applicant will support the acquisition, and
reduction of pointed data from the EUVE satellite. Duties will include
monitoring the progress of observation scheduling and data acquisition,
pipeline processing and data reductions and analysis. The researcher will
assist Guest Investigators, through the Guest Observer program and the EUVE
Archive program, in understanding the performance of the EUVE scientific
instruments as well as provide scientific advice regarding use of the EUVE
spectrometer analysis packages, written primarily in IRAF. Additional duties
will involve assisting in the development of complex data analysis algorithms
and models, to be made available to the Guest Investigator community in the
EUVE IRAF packages and EUVE public archive.
The work will be performed under the direction of the EUVE Science Support
Project Manager, and will interact with the associated science and programming
staff in the EUVE Public Archive and Guest Observer Center. A fraction of time
(10%) will be available to allow pursuit of independent research.
Applicants must have a Ph.D. in astronomy, physics, or a related field.
Experience supporting NASA Archival Research, Guest Observer, and Guest
Investigator programs required. Experience in satellite or ground-based
astronomical data analysis and the ability to carry out research in the field
of EUV astronomy is highly desirable. Experience with IRAF would be most
helpful.
Applications should include a curriculum vitae, bibliography and three
letters of recommendation and should be submitted by April 30, 1994. EOE/AAE.
Staff Research Associate I
Box 03-144-10
Personnel Office
University of California
2200 University Ave.
Berkeley, California 94720
The Center for Extreme Ultraviolet Astrophysics, seeks applicants for the
position of Staff Research Associate I. Duties include support of astronomical
research and data acquisition, reduction, and analysis for the Extreme
Ultraviolet Explorer (EUVE) Satellite Project. Work will be related to the
reduction of EUVE science data. The Staff Research Associate will assist
scientists in the development and application of data analysis programs to data
taken using ground-based astronomical instruments. Process data from raw
telemetry into time-tagged photon files and spectra. Monitor processing flow,
involvement in processing Guest Observer multispectral data into primary and
secondary products. Other duties include producing documentation of results,
and publication support assisting in the simulation of scientific data related
to the EUVE Satellite Project.
Qualifications: Background in Astronomy, Physics or other applicable
science, plus experience in the kind of work to be performed is required.
Demonstrated knowledge of general astronomical data reduction and acquisition
techniques is required. Experience with FORTRAN or C programming is required.
Knowledge of the IRAF system and packages required. Knowledge of UNIX
operating system is highly desired.
Applications should include a curriculum vitae and names of three references
and be submitted promptly. Position is open until filled. No resumes will be
accepted after May 25, 1994.
Associate Development Engineer
Box 03-143-10
Personnel Office
University of California
2200 University Ave.
Berkeley, California 94720
Associate Development Engineer, Center for Extreme Ultraviolet Astrophysics,
UC Berkeley NASA Extreme Ultraviolet Explorer Satellite Project. Oversee the
engineering efforts of the Science Operations Center. Coordinate the activities
of payload subsystems engineers in both routine analysis and anomaly resolution.
Provide scheduling and planning expertise on engineering activities. Determine
payload and spacecraft activities needed for calibration and maintenance.
Identify operational areas and develop training strategies. Identify future
needs for the extended mission engineering effort. Qualifications: Background
in electrical, mechanical or aerospace engineering. Experience with engineering
analysis techniques. Good communications skills. Unix experience. Familiarity
with NASA institutions, research projects and satellite operation procedures
preferred. Managerial experience preferred. Experience with Unix shell and C
programming helpful.
Send resume and three reference names by 4/20/94.
For additional job information, contact Cathie Jones @ 510-642-1263.
---------------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme Ultra-
violet Astrophysics, University of California, Berkeley, CA 94720, USA.
The opinions expressed are those of the authors. EUVE Principal Investi-
gators and Newsletter Publishers: Drs. R.F. Malina and C.S. Bowyer. EGO
and Archive Science Manger: C.A. Christian. Archive Manager and News-
letter Editor: B.A. Stroozas. Funded by NASA contracts NAS5-30180 and
NAS5-29298. Send newsletter correspondence to: ceanews@cea.berkeley.edu.
The EUVE project is managed by NASA's GSFC. The GSFC Project Manager:
Paul Pashby, Project Scientist: Dr. Yoji Kondo, Deputy Project Scientist:
Dr. Ronald Oliversen. NASA HQ Program Scientist: Dr. Robert Stachnik,
Deputy Program Scientist: Dr. D. Buzasi, Program Manager: Dr. G. Riegler.
GSFC Project Operations Director: Mr. Kevin Hartnett. Information on the
EUVE Guest Observer Program is available from: Dr. Y. Kondo, Mail Code
684, GSFC, Greenbelt, MD 20771 at (301) 286-6247 or e-mail to
euve@stars.span.nasa.gov.
END-----------EUVE------------ELECTRONIC---------------NEWS-------------END
|
| 770.37 | May 15 | MTWAIN::KLAES | Keep Looking Up | Mon May 16 1994 12:44 | 617 |
| From: VERGA::US4RMC::"ceanews@cea.Berkeley.EDU" "EUVE Electronic Newsletter
distribution" 15-MAY-1994 16:04:02.01
To: euvenews@cea.Berkeley.EDU
CC:
Subj: EUVE Electronic Newsletter
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
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Vol 4, No. 5 15 May 1994 ISSN 1065-3597
---------------------------------------------------------------------------
Notes from the Editor
=====================
by Brett A. Stroozas, Data Analysis Support Staff (DASS)
and Archive Manager
Welcome to the electronic newsletter for NASA's Extreme Ultraviolet Explorer
satellite (EUVE), which is compiled and published monthly by the EUVE Public
Science Archive group at the Center for EUV Astrophysics (CEA) in Berkeley,
CA. As mentioned in the previous issue (v4.4, 12 April 1994), EUVE suffered
its first major hardware failure with the loss of its "B" side transmitter on
2 April. The Flight Operations Team at Goddard Space Flight Center (GSFC)
quickly switched to the "A" side, insuring no loss of science data. Except
for this incident, which continues to be investigated, the EUVE observatory
performed well throughout the month of April, completing observations of the
following Guest Observer (GO) targets: MRK 421 (BL Lac), LB 1919 (WD), and
MRK 279 (AGN).
The contents of this issue of the EUVE electronic newsletter are as follows:
1. Notes on the Upcoming AAS Meeting
1.1 EUVE User's Committee Meeting at AAS
1.2 List of EUVE Abstracts for AAS
2. Notes from the EUVE Guest Observer Center
2.1 GO Program NRA Schedule Update
2.2 Cycle II Dithered Target List
3. Abstracts of Recently *Accepted* EUVE Papers
4. Educational Outreach Activities at CEA
4.1 NASA Astronaut Visits Bay Area
4.2 Education Page in Mosaic
5. Notes from the EUVE Science Archive
5.1 Data Release List for June 1994
5.2 CD-ROM Volume 2, Number 2 for AAS
5.3 Status Report on EUVE Publications
5.4 Accessing the Archive
6. Job Listings at CEA
To comment on, make suggestions for, or request subscriptions to the EUVE
electronic newsletter, send e-mail to ceanews@cea.berkeley.edu (Internet).
1. Notes on the Upcoming AAS Meeting
====================================
1.1 EUVE User's Committee Meeting at AAS
----------------------------------------
A special EUVE User's Committee meeting will be held at the 184th meeting
of the American Astronomical Society (AAS) in Minneapolis, MN during the week
of 29 May - 2 June 1994. The User's Committee meeting is scheduled for the
lunch break on Tuesday, 31 May in Directors Row 3. Planned topics of
discussion are a current update on EUVE and the ongoing efforts to extend the
EUVE mission. Dr. Harry Shipman, chairman of the User's Committee, is the
coordinator of this meeting and will announce further information in the near
future. The interest and input of the user community is extremely important
to the future of EUVE and we strongly encourage everyone to attend.
PLEASE NOTE: The meeting room is *incorrectly* noted in the final schedule
as Directors Row 1. The correct location for this meeting is Directors Row 3
as mentioned above.
1.2 List of EUVE Abstracts for AAS
----------------------------------
The following EUVE abstracts will be presented at the upcoming 184th AAS
meeting in Minneapolis, MN. The abstracts have been listed by session and
abstract number; all those listed are poster displays except session 18 which
is oral:
[05.03] THE FLARE-ONA OF 31 COMAE, T.R. Ayers and A. Brown
[05.08] EUVE SPECTRA OF ALPHA AURIGAE (CAPELLA) AT DIFFERENT PHASES,
A.K. Dupree, N.S. Brickhouse, G.A. Doschek, G.J. Hanson,
and J.C. Raymond
[05.10] CONSTRAINTS ON EUV SPECTRAL DIAGNOSTICS OF CAPELLA, N.S. Brickhouse,
A.K. Dupree and J.C. Raymond
[05.14] GHRS SPECTRA OF THE ACTIVE CHROMOSPHERE BINARY V711 TAU (HR 1099),
R.C. Dempsey, J.E. Neff and J.L. Linsky
[05.17] EUVE CORONAL SPECTROSCOPY OF THE RSCVN BINARIES SIGMA^2 CRB AND II
PEG, A. Brown, J.L. Linsky and R. Dempsey
[05.18] EMISSION LINES IN THE EUVE SPECTRA OF EQ PEGASI,
B.C. Monsignori-Fossi, M. Landini, R. Pallavicini, and A. Fruscione
[05.19] EUVE OBSERVATIONS OF A RARE IMPULSIVE FLARE ON EV LAC,
C.W. Ambruster, A. Brown, B. Pettersen, and R.E. Gershberg
[05.20] THE EUV ROTATION-ACTIVITY RELATION FOR LATE-TYPE STARS,
M. Mathioudakis, A. Fruscione, J.J. Drake, K. McDonald, S. Bowyer,
and R.F. Malina
[05.21] THE SOLAR FIP EFFECT DETERMINED FROM FULL DISK OBSERVATIONS,
J.M. Laming, J.J. Drake and K.G. Widing
[05.22] THE FIRST MEASUREMENT OF STELLAR CORONAL ABUNDANCES: THE ABSENCE OF
THE FIP EFFECT IN THE CORONA OF PROCYON, J.J. Drake, J.M. Laming,
K.G. Widing, J.H.H.M. Schmitt, B. Haisch, and S. Bowyer
[07.01] CARBON-ENRICHMENT IN THE ATMOSPHERE OF THE COOL DO WHITE DWARF MCT
0501-2858, S. Vennes, A.K. Pradhan, G. Fontaine, J. Dupuis,
and F. Wesemael
[07.08] EUV ABSORPTION SPECTROSCOPY OF THE DA WHITE DWARF STAR GD 394,
H.L. Shipman and D.S. Finley
[08.02] DETECTION OF THE BINARY MILLISECOND PULSAR J0437-4715 WITH THE
EXTREME ULTRAVIOLET EXPLORER, J. Edelstein, R.S. Foster and S. Bowyer
[08.05] EUVE OBSERVATIONS OF THE MIDDLE-AGED PULSAR PSR 0656+14, J.P. Finley,
H. Ogelman and J. Edelstein
[11.02] EUVE SPECTROGRAPHIC RESULTS ON THE BL LAC OBJECT PKS 2155-304,
C. Hwang, S. Bowyer, S. Kahn, and A. Konigl
[18.04] A SATELLITE OPERATIONS CLASS FOR TEACHERS, I. Hawkins, S. Lea,
R. Battle, J. Moriarta, and R.F. Malina
[18.05] ELECTROMAGNETIC RADIATION: A CURRICULUM UNIT FOR HIGH SCHOOL
STUDENTS, N. Levandovsky, I. Hawkins and R.F. Malina
[28.06] THE SECOND EUVE SOURCE CATALOG, J. Lewis, S. Bowyer, M. Lampton,
X. Wu, R. Lieu, J. Drake, and R.F. Malina
[29.01] EVIDENCE FOR HOMOGENEOUS IONIZATION OF HELIUM IN THE LOCAL
INTERSTELLAR MEDIUM FROM EUVE SPECTROSCOPY OF HOT DA STARS, J. Dupuis,
S. Vennes, S. Bowyer, A.K. Pradhan, and P. Thejll
[29.14] THE FIRST DIRECT MEASUREMENT OF THE THERMAL PRESSURE OF THE HOT
INTERSTELLAR MEDIUM, R. Lieu, S. Bowyer, M. Lampton, S.D. Sidher,
and J. Knude
[45.03] EUVE OBSERVATIONS OF CATACLYSMIC VARIABLES, J. Warren, J.V. Vallerga
and O.H.W. Siegmund
[45.04] EUVE OBSERVATIONS OF SS CYGNI, C.W. Mauche, J.C. Raymond,
J.V. Vallerga, J.K. Warren, and J.A. Mattei
[45.06] EXTREME ULTRAVIOLET OBSERVATIONS OF THE MAGNETIC CATACLYSMIC VARIABLE
RE1149+28, S.B. Howell, M. Sirk and J. Mittaz
[45.07] EUVE SPECTRAL OBSERVATIONS OF A FLARE ON AD LEONIS, S.L. Cully,
G.H. Fisher, S.L. Hawley, and T. Simon
[47.02] ANALYSIS OF THE EUVE SURVEY OBSERVATIONS OF NOVA CYGNI 1992,
J. MacDonald and S. Vennes
2. Notes from the EUVE Guest Observer Center
============================================
2.1 GO Program NRA Schedule Update
----------------------------------
by Anne Miller, EGO Center Technical Writer
The dates for release of the next EUVE NASA Research Announcement (NRA),
and the projected deadline for proposal submission, have been revised to avoid
conflict with the schedules for other NRAs. The new dates are:
NRA release: 15 Jun 1994
Proposal due date: 16 Sep 1994
Peer Review: Nov 1994
Start of observations: Feb 1995
These dates supersede those published in the last issue of this newsletter
(v4.4, 12 April 1994). They remain *tentative*, and are subject to change.
2.2 Cycle II Dithered Target List
---------------------------------
by Eric Olson, EGO Support Manager
It has been known for some time that the EUVE spectrometer detectors exhibit
a characteristic fixed-pattern-noise (FPN) that results when the locations of
photon events near the boundaries of "bundles" of micro-channel fibers in the
EUVE micro-channel plate detectors are shifted. Because EUVE sees so few
EUV-bright sources, the probability is very small for accumulating sufficient
events to generate a flat-field which would remove all of the variations caused
by the FPN. Recent tests, however, indicate that it is possible to alleviate
much of the FPN by pointing the spectrometer at a series of randomly chosen
locations near the target, rather than at a single RA/Dec for the entire
observation. This technique is known as "dithering". Enclosed below is the
list of Cycle II targets that are being considered for dithered observations.
For more information on FPN and the dithering technique, contact the EGO Center
(egoinfo@cea.berkeley.edu). For information on or comments regarding dithered
observations, contact Eric Olson at CEA or Dr. Ron Oliversen at GSFC.
Cycle II Dithered Target List
Target RA J2000 Dec J2000
Name (hh:mm:ss) (dd:'':"") Notes
--------------------- ------------ ------------- -----
EU1032+53.4 10:32:10.00 53:29:11.0 r
EU2214-49.3 22:14:12.00 -49:19:26.0 r
EUVEJ0326+28.7 03:26:35.10 28:42:59.3 g e
EUVEJ0516+45.9 05:16:41.30 45:59:53.0 g o e
EUVEJ0622-17.9 06:22:41.90 -17:57:21.5 r o
EUVEJ0658-28.9 06:58:37.50 -28:58:19.6 r o
EUVEJ0739+05.2 07:39:20.40 05:14:21.2 g o e
EUVEJ0743+28.8 07:43:18.70 28:53:12.1 g e
EUVEJ1334+37.1 13:34:47.40 37:10:57.1 g e
EUVEJ2337+46.4 23:37:33.00 46:27:50.5 g e
EUVE_J0030-63.4 00:29:56.60 -63:24:57.1 r
EUVE_J0715-70.4 07:15:10.00 -70:24:44.0 r
FEIGE24 02:35:07.58 03:43:56.1 r
G191_B2B 05:05:30.00 52:49:53.0 r o
GD659 00:53:18.00 -33:01:00.0 r
GD80 06:54:13.96 -02:09:23.96 r
GD_246 23:12:22.00 10:47:04.0 r
J1316+29.0 13:16:22.60 29:05:38.0 r o *
LB1628 02:30:52.49 -47:55:26.4 g f
LB1919 10:59:14.60 51:24:28.0 r o
LVC_88_+36_-2 17:05:04.71 59:17:00.0 r
RE2009-60 20:09:06.20 -60:25:30.0 r
RE_0623-374 06:23:12.50 -37:41:29 r o
SS_CYG 21:42:42.30 43:35:08.0 r
UZ_FOR 03:35:29.00 -25:44:26.0 r
V471_TAU 03:47:33.40 17:14:48.0 r
VW_HYI 04:09:11.30 -71:17:42.0 r
WD_0131-163 01:34:24.29 -16:06:53.7 r
Notes:
r = Recommended by CEA
g = Recommended by GO
o = Observation completed or in short term schedule
e = Emission line source
f = Faint continuum source
* = To be observed again
3. Abstracts of Recently *Accepted* EUVE Papers
===============================================
Included below are abstracts of EUVE-related papers recently *accepted*
for publication. GOs are encouraged to contribute *accepted* abstracts for
inclusion in future editions of this newsletter and for posting under the EGO
Center Mosaic "Home Page". All abstracts should be sent to
egoinfo@cea.berkeley.edu.
For those papers authored by CEA scientists, the EUVE publication number is
indicated. Unless otherwise noted, researchers may obtain (p)reprints of these
papers by sending an e-mail request along with the publication number(s) of
interest to pub@cea.berkeley.edu.
--------------------------------------------------------------
THE EUV SPECTRUM OF AU MIC: TEMPERATURE AND DENSITY DIAGNOSTIC FROM EUVE
SPECTROMETER OBSERVATIONS
B.C. Monsignori Fossi and M. Landini
To appear in Astronomy and Astrophysics.
EXOSAT and IUE observations of the active star AU Mic are used to develop
a model of the differential emission measure distribution (DEM) versus
temperature. The signals detectable by the Extreme UltraViolet Explorer
Spectrometers are predicted. The computation indicates the presence of
several highly ionized iron lines in the EUV spectral region. These lines
are identified in the observations of AU Mic performed by the Short (70-190 A)
and Medium (140-380 A) Wavelength Spectrometers on EUVE. Using the recorded
EUVE spectra a more accurate DEM model for the transition region and corona
of the star has been evaluated and using density sensitive lines an upper
limit on the electron density has been put.
--------------------------------------------------------------
EUVE SPECTROSCOPY OF EPSILON CMA (B2 II) FROM 70 A TO 730 A
J.P. Cassinelli, D.H. Cohen, J.J. MacFarlane, J.E. Drew, A.E. Lynas-Gray,
M.G. Hoare, J.V. Vallerga, B.Y. Welsh, P.W. Vedder, I. Hubeny, and T. Lanz
To appear in The Astrophysical Journal.
We present spectra of the brightest stellar source of extreme ultraviolet
(EUV) radiation longward of 400 A, the B2 II star, Epsilon CMa. These data were
taken with the three spectrometers aboard the NASA Extreme Ultraviolet Explorer
satellite (EUVE) during the first cycle of pointed observations. We report
on our initial studies of the continuum and line spectrum of the stellar
photosphere in the 320 to 730 A region, and on the wind emission lines observed
in the 170-375 A region. This is the first EUV spectrum of an early-type star,
and thus makes Epsilon CMa the most comprehensively observed B star from the
X-ray to infrared regimes.
The radiation in both the H Lyman continuum and HeI continuum (shortward of
504 A) are found to be significantly greater than predicted by both LTE and
non-LTE model atmospheres. Since Epsilon CMa also exhibits a mid-infrared
excess, this points to the outer layers being warmer than the models indicate.
The anomalously large Lyman continuum flux, combined with the very low column
density measured in the direction towards this star implies that it is the
dominant source of hydrogen ionization of the local interstellar medium in the
immediate vicinity of the sun. All of the lines predicted to be strong from
model atmospheres are present and several wind absorption features are also
identified. We have detected emission lines from highly ionized iron, ranging
from Fe^8 to Fe^15, which arise in the X-ray producing region. The lines are
consistent with the ROSAT PSPC observations if a multi-temperature emission
model is used, and the assumption is made that there is significant absorption
beyond that of the neutral phase of the ISM. The EUV spectrum shows a strong
HeII Lyman-alpha emission at 304 A. This line cannot be formed in the upper
regions of the photosphere, but rather is due to the recombination of He++,
which is itself produced by the X-ray and EUV (lambda < 228 A) radiation
present in the outer atmosphere. The spectrum also shows strong OIII 374 A
line emission produced by the Bowen fluorescence mechanism, which has not
previously been observed in the spectra of hot stars.
Keywords: stars: early type, individual (Epsilon CMa), photospheres, winds,
shocks -- extreme ultraviolet: spectroscopy -- Bowen fluorescence
-- interstellar medium: local, ionization
--------------------------------------------------------------
INTERSTELLAR MEDIUM CONTINUUM, AUTOIONIZATION, AND LINE ABSORPTION IN THE
EXTREME ULTRAVIOLET
T. Rumph, S. Bowyer, and S. Vennes
To appear in The Astronomical Journal. [CEA Publication #584.]
We provide a new estimate of the effective absorption cross section of the
interstellar medium at extreme ultraviolet wavelengths. The cross section for
neutral helium is discussed in detail. Two spectral features of interstellar
neutral helium, the 504 A ionization edge and the autoionization resonance
feature at 206 A, are detectable with existing instrumentation. Measurements
of the autoionization feature in continuum sources will provide a direct
estimate of the intervening neutral helium column; in many cases this will be
the only method to obtain this parameter. Although continuum metal opacities
are negligible at wavelengths greater than 50 A, we find that metal line
features should be detectable in continuum sources with high signal to noise
observations. A selection of some of the most prominent lines expected is
provided.
--------------------------------------------------------------
EUVE OBSERVATIONS OF THE MOON
G. Randall Gladstone, John S. McDonald, William T. Boyd, and Stuart Bowyer
To appear in Geophysical Research Letters, 21(6), pp. 461-464, 1994. [CEA
Publication #583.]
During its all-sky survey, the Extreme Ultraviolet Explorer (EUVE) satellite
observed the Moon several times at first and last quarters, and once near the
lunar eclipse of December 10, 1992. We present here a portion of this data, in
the form of extreme-ultraviolet (EUV) images of the Moon and derived geometric
albedos. Extreme ultraviolet observations of the Moon are of considerable
interest, since it has been speculated that lunar EUV emissions may be dominated
by L- and M-shell X-ray fluorescence and may provide a useful diagnostic of
surface elemental abundances. From the EUVE photometer data we obtain average
geometric albedos of 0.15% (+/- 0.03%), 3.1% (+/- 0.3%), and 3.5% (+/- 0.3%),
over wavelength intervals of 150-240 A, 400-580 A, and 550-650 A, respectively.
An upper limit geometric albedo of 0.13% is obtained for the wavelength
interval 75-180 A. Also, using previously published ROSAT data, we estimate a
lunar geometric albedo of 0.014% (+/- 0.002%) over the wavelength interval
50-80 A. These EUV albedos (and previously published far-ultraviolet albedos)
are well fit by the scaled reflectivities of SiO_2 and Al_2O_3. Over the
wavelength ranges of the EUVE photometers, the observed brightness of the Moon
seems to be largely consistent with reflected sunlight rather than X-ray
fluorescence. Since the L- and M-shell fluorescence signal is expected to be
carried by only a small number of emission lines, however, it will require EUV
observations of higher spectral resolution to determine their exact
contribution, if any, to the lunar EUV spectrum.
--------------------------------------------------------------
A CME MODEL FOR THE 1992 JULY 15 FLARE ON AU MICROSCOPII OBSERVED BY EUVE
Scott L. Cully, George H. Fisher, Mark J. Abbott, and Oswald H.W. Siegmund
To appear in The Astrophysical Journal. [CEA Publication #581.]
The dM1e flare star AU Microscopii (AU Mic) was observed by the EUVE Deep
Survey Instrument on 1992 July 14-18. A large flare was detected in the Deep
Survey Lexan/Boron (DS Lex/B) (65-190 A) band and the SW (70-190 A) and MW
(140-380 A) spectrometers. The flare consisted of a sharp impulsive peak
lasting approximately 2 hours followed by a decaying tail lasting about a day.
We present a simple, single temperature, dynamic model for the flare decay
which is consistent with the the DS Lex/B light curve and reproduces the
strongest, high temperature spectral lines in the released EUVE spectra. In
this model, we assume the long decay time is due to an ejected, magnetically
confined, low beta plasmoid expanding self similarly in the ambient medium in
a manner reminiscent of solar coronal mass ejections. We demonstrate that the
long tail of the DS Lex/B light curve can be explained by rapid expansion,
causing the plasma to become tenuous sufficiently quickly that it avoids
catastrophic radiative cooling. From this model, we estimate the mass of the
plasmoid to be 1e20 g and the total energy of the event to be 1e36 ergs.
These values are approximately 1e4 times as large as those seen during the
largest solar CME events. We argue that the results of our model are consistent
with other measurements of stellar flare parameters. We also estimate a mass
loss rate of a few times 10-13 M_Solar yr^(-1) and discuss the role of mass
loss from dMe stars in the mass balance of the interstellar medium. We estimate
the rotational braking time scale from these events to be less than 500 million
years and suggest that CME's may be an important source of angular momentum
loss from late type stars.
--------------------------------------------------------------
4. Educational Outreach Activities at CEA
=========================================
by Dr. Isabel Hawkins, CEA Scientist
4.1 NASA Astronaut Visits Bay Area
----------------------------------
The CEA Education Outreach Program, headed by Dr. Isabel Hawkins, had the
pleasure of hosting a 1-day visit by NASA Astronaut Jeffrey A. Hoffman, the
astrophysicist who put eyeglasses on the Hubble Space Telescope (HST).
Dr. Hoffman's schedule included an informal lunch with old friends from
Harvard and MIT and a tour of CEA where he interacted with CEA scientists
and staff, obtaining a close look at EUVE data and a hands-on introduction
to Mosaic.
After a technical presentation at CEA to an audience of eighty University
of California, Berkeley, faculty and staff, Astronaut Hoffman shared his
experiences during dinner with a group of thirty teachers, high school
students, and other professional educators.
The last event of the day was a nontechnical presentation by Dr. Hoffman
entitled "THE ULTIMATE ROADSIDE REPAIR" which took place at the Lawrence Hall
of Science. This event, for an audience of 300 people, was sponsored jointly
by CEA and the Lawrence Hall of Science. During his presentation, which
included spectacular film-footage, Astronaut Hoffman gave a firsthand account
of the capture and repair of HST. During an 11-day flight of the Space Shuttle
Endeavour in December 1993, the HST was restored to full capacity through a
record-setting five space walks by Dr. Hoffman and his fellow astronauts.
After his presentation, Dr. Hoffman answered questions from the public and
signed autographs.
4.2 Education Page in Mosaic
----------------------------
The Education Outreach Program at CEA will release its Mosaic page within
the next few weeks. See the CEA Home Page (http://cea-ftp.cea.berkeley.edu)
for more details.
5. Notes from the EUVE Science Archive
======================================
by Brett A. Stroozas, DASS/Archive Manager
5.1 Data Release List for June 1994
-----------------------------------
The table below lists the GO observations which become public on 1 June
1994. For each entry is given the target name, the approximate exposure time
in kiloseconds, the GMT start and end date(s) for the observation, the spectral
type of the target, an indication of which (if any) EUVE CD-ROM on which the
observation appears, and the data identification code. All public data sets
may be ordered from the archive via CEA electronic or postal mail. Please be
sure to include in your order the DataID(s) of interest.
======================================================================
Target ~Exp Observation Date(s) SpT CD-ROM DataID
Name (ksec) Start End
======================================================================
31_COM 73 11 Feb 1993 - 13 Feb 1993 G0II ---- go0028
AD_LEO 90 1 Mar 1993 - 3 Mar 1993 M4.5 2.2b go0029
ALPHA_CEN_A 24 31 May 1993 - 1 Jun 1993 G0 ---- go0031
ALPHA_CEN_A 30 7 Jun 1993 - 8 Jun 1993 G0 ---- go0032
ALPHA_CEN_A 55 29 May 1993 - 31 May 1993 G0 2.2b go0030
AN_UMA 45 27 Feb 1993 - 1 Mar 1993 CV 2.2c go0033
AU_MIC 52 22 Jul 1993 - 23 Jul 1993 M1e ---- go0034
EPSILON_CMA 65 16 Jan 1993 - 18 Jan 1993 B2I 2.2c go0035
JUPITER 65 30 Mar 1993 - 1 Apr 1993 SS 2.2c go0036
MCT2153-4156 2 8 Aug 1993 - 8 Aug 1993 WD ---- go0037
PSR0656+14 104 30 Jan 1993 - 3 Feb 1993 Puls ---- go0038
RE0515+324 71 24 Jan 1993 - 26 Jan 1993 WD ---- go0039
RE1027+322 108 4 Mar 1993 - 8 Mar 1993 NOID ---- go0040
RE1032+532 56 3 Feb 1993 - 5 Feb 1993 WD ---- go0041
RE1149+284 71 22 Feb 1993 - 25 Feb 1993 NOID ---- go0042
WD1254+223 28 5 Apr 1993 - 6 Apr 1993 WD ---- go0044
WD1254+223 55 9 Feb 1993 - 11 Feb 1993 WD 2.2a go0043
WD1620-391 3 2 Jul 1993 - 2 Jul 1993 WD ---- go0047
WD1620-391 53 19 May 1993 - 21 May 1993 WD ---- go0045
WD1620-391 54 30 Jun 1993 - 2 Jul 1993 WD ---- go0046
WD1845+019 2 15 Jun 1993 - 16 Jun 1993 WD ---- go0048
WD1845+019 31 22 Jun 1993 - 23 Jun 1993 WD ---- go0049
WD2309+105 28 30 Aug 1993 - 31 Aug 1993 WD ---- go0050
YZ_CMI 75 25 Feb 1993 - 27 Feb 1993 M4.5 ---- go0051
======================================================================
5.2 CD-ROM Volume 2, Number 2 for AAS
-------------------------------------
Volume 2, Number 2 (A/B/C) of the EUVE CD-ROM series will be distributed at
the upcoming AAS meeting. This set of CDs contains nine selected spectrometer
observations, arranged thematically on three discs: disc A contains the three
white dwarfs HZ43 (observed 18-19 February 1993, ~40 ksec), WD1254+223 (9-11
February 1993, ~55) and WD2309+105 (27-28 September 1992, ~55); disc B contains
the three late-type stars AD Leo (1-3 March 1993, ~90), alpha Cen A (29-31 May
1993, ~55) and sigma Gem (6-7 February 1993, ~55); and disc C contains the
Cataclysmic Variable AN UMa (27 February - 1 March 1993, ~45), the early-type
star epsilon CMa (16-18 January 1993, ~65) and the planet Jupiter (30 March -
1 April 1993, ~65). Also included are EUVE images, simulations, animations,
videos, publications, and a variety of mission-related documents. All EUVE
CD-ROMs may be ordered from the Archive via electronic and postal mail; the
DataIDs for Volume 2, Number 2 (A/B/C) are cdrom2.2a, cdrom2.2b and cdrom2.2c,
respectively.
5.3 Status Report on EUVE Publications
--------------------------------------
As of April 1994 CEA is aware of a total of 68 EUVE publications that have
appeared in the literature. These publications are broken down in the table
below: "RJ" indicates a refereed journal and "NRJ" indicates a non-refereed
one; non-CEA indicates publications by non-CEA scientists (i.e. Guest Observers)
and CEA indicates those by CEA scientists (which includes both Guest Observer
and sky survey science).
RJ NRJ TOTAL
-- --- -----
non-CEA 8 3 11
CEA 38 19 57
--------- -- -- --
TOTAL 46 22 68
The Archive is generating a bibliography of EUVE publications which will be
available in the Archive section within CEA Mosaic. Again, we encourage GOs
to send abstracts of their papers to the EGO Center (egoinfo@cea.berkeley.edu).
5.4 Accessing the Archive
-------------------------
Listed below are the various methods for accessing EUVE archival material:
o CEA WWW Server:
http://cea-ftp.cea.berkeley.edu (Mosaic/lynx remotely)
telnet cea-ftp.cea.berkeley.edu 200 (lynx locally at CEA)
o NASA's ADS (general and account information):
http://adswww.colorado.edu/adswww/adshomepg.html (Mosaic/lynx)
ads@cuads.colorado.edu
o CD-ROM Series: Volumes 1.1, 2.1, and 2.2 (seven separate CDs) available
o e-mail: archive@cea.berkeley.edu
(include word "help" -- quotes omitted -- as body of message)
o anonymous FTP (or gopher): cea-ftp.cea.berkeley.edu
o EUVE Electronic Newsletters: ceanews@cea.berkeley.edu (to subscribe)
o Postal Mail:
The EUVE Public Science Archive
Center for EUV Astrophysics
2150 Kittredge St.
Berkeley, CA 94720
510-642-3032 (voice) or 510-643-5660 (fax)
archive@cea.berkeley.edu
6. Job Listings at CEA
======================
by Cathie Jones, CEA Personnel Manager
CEA is currently accepting applications for the following job positions.
--------------------------------------------------------------
Postgraduate/Assistant Research (depending on experience)
University of California
Center for EUV Astrophysics
Attn: Cathie Jones/Personnel
2150 Kittredge St.
Berkeley, CA 94720
The Extreme Ultraviolet Explorer (EUVE) Program at the Center for EUV
Astrophysics, of the University of California, Berkeley, has opening for a
Research Scientist. Successful applicant will support the acquisition, and
reduction of pointed data from the EUVE satellite. Duties will include
monitoring the progress of observation scheduling and data acquisition,
pipeline processing and data reductions and analysis. The researcher will
assist Guest Investigators, through the Guest Observer program and the EUVE
Archive program, in understanding the performance of the EUVE scientific
instruments as well as provide scientific advice regarding use of the EUVE
spectrometer analysis packages, written primarily in IRAF. Additional duties
will involve assisting in the development of complex data analysis algorithms
and models, to be made available to the Guest Investigator community in the
EUVE IRAF packages and EUVE public archive.
The work will be performed under the direction of the EUVE Science Support
Project Manager, and will interact with the associated science and programming
staff in the EUVE Public Archive and Guest Observer Center. A fraction of time
(10%) will be available to allow pursuit of independent research.
Applicants must have a Ph.D. in astronomy, physics, or a related field.
Experience supporting NASA Archival Research, Guest Observer, and Guest
Investigator programs required. Experience in satellite or ground-based
astronomical data analysis and the ability to carry out research in the field
of EUV astronomy is highly desirable. Experience with IRAF would be most
helpful.
Applications should include a curriculum vitae, bibliography and three
letters of recommendation and should be submitted by April 30, 1994. EOE/AAE.
--------------------------------------------------------------
Staff Research Associate I
Box 03-144-10
Personnel Office
University of California
2200 University Ave.
Berkeley, California 94720
The Center for Extreme Ultraviolet Astrophysics, seeks applicants for the
position of Staff Research Associate I. Duties include support of astronomical
research and data acquisition, reduction, and analysis for the Extreme
Ultraviolet Explorer (EUVE) Satellite Project. Work will be related to the
reduction of EUVE science data. The Staff Research Associate will assist
scientists in the development and application of data analysis programs to data
taken using ground-based astronomical instruments. Process data from raw
telemetry into time-tagged photon files and spectra. Monitor processing flow,
involvement in processing Guest Observer multispectral data into primary and
secondary products. Other duties include producing documentation of results,
and publication support assisting in the simulation of scientific data related
to the EUVE Satellite Project.
Qualifications: Background in Astronomy, Physics or other applicable
science, plus experience in the kind of work to be performed is required.
Demonstrated knowledge of general astronomical data reduction and acquisition
techniques is required. Experience with FORTRAN or C programming is required.
Knowledge of the IRAF system and packages required. Knowledge of UNIX
operating system is highly desired.
Applications should include a curriculum vitae and names of three references
and be submitted promptly. Position is open until filled. No resumes will be
accepted after May 25, 1994.
---------------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme Ultraviolet
Astrophysics, University of California, Berkeley, CA 94720, USA. The opinions
expressed are those of the authors. EUVE Principal Investigators and Newsletter
Publishers: Drs. R.F. Malina and C.S. Bowyer. EGO and Archive Science Manger:
C.A. Christian. Archive Manager and Newsletter Editor: B.A. Stroozas. Funded
by NASA contracts NAS5-30180 and NAS5-29298. Send newsletter correspondence
to: ceanews@cea.berkeley.edu. The EUVE project is managed by NASA's GSFC.
The GSFC Project Manager: Paul Pashby, Project Scientist: Dr. Yoji Kondo,
Deputy Project Scientist: Dr. Ronald Oliversen. NASA HQ Program Scientist:
Dr. Robert Stachnik, Deputy Program Scientist: Dr. D. Buzasi, Program Manager:
Dr. G. Riegler. GSFC Project Operations Director: Mr. Kevin Hartnett.
Information on the EUVE Guest Observer Program is available from: Dr. Y.
Kondo, Mail Code 684, GSFC, Greenbelt, MD 20771 at (301) 286-6247 or e-mail to
euve@stars.span.nasa.gov.
END-----------EUVE------------ELECTRONIC---------------NEWS-------------END
% ====== Internet headers and postmarks (see DECWRL::GATEWAY.DOC) ======
% Date: Sun, 15 May 1994 12:15:02 -0700
% From: EUVE Electronic Newsletter distribution <ceanews@cea.Berkeley.EDU>
% Message-Id: <199405151915.MAA02064@imperial.cea.berkeley.edu>
% To: euvenews@cea.Berkeley.EDU
% Subject: EUVE Electronic Newsletter
|
| 770.38 | June 14 | MTWAIN::KLAES | Keep Looking Up | Wed Jun 15 1994 14:19 | 479 |
| From: US4RMC::"ceanews@imperial.cea.berkeley.edu" "EUVE Electronic Newsletter
distribution" 14-JUN-1994 18:08:03.43
To: usenet-space-news@arc.nasa.gov
CC:
Subj: EUVE Electronic Newsletter
EEEEEEEEEEE U U V V EEEEEEEEEEE
E U U V V E
E U U V V E
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E U U V V E
E U U V V E
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
---------------------------------------------------------------------------
Vol 4, No. 6 14 Jun 1994 ISSN 1065-3597
---------------------------------------------------------------------------
Notes from the Editor
=====================
by Brett A. Stroozas, Data Analysis Support Staff (DASS)
and Archive Manager
Welcome to the electronic newsletter for NASA's Extreme Ultraviolet
Explorer (EUVE) satellite, which is compiled and published monthly by
the EUVE Public Science Archive group at the Center for EUV
Astrophysics (CEA) in Berkeley, CA. The EUVE observatory performed
well throughout the month of May, completing observations of the
following Guest Observer (GO) targets: the planet Jupiter, the star
44i Boo, the B8Vne star HR4804, the BL Lac object PKS2155+304, and the
White Dwarf HZ43. A four-day engineering test was also conducted;
analysis of the data is in progress.
The contents of this issue of the EUVE electronic newsletter are as follows:
1. EUVE User's Committee Extended Mission Proposal Presented at AAS
2. Notes from the EUVE Guest Observer Program
2.1 UCB Principal Investigator Guaranteed Time Observations (GTO)
2.2 Target of Opportunity: VW Hyi
2.3 Third EUVE GO NRA
3. Abstracts of Recently *Accepted* EUVE Papers
4. NASA's EUVE Observatory Researchers Share a Ride with Educators on the
Information Superhighway
5. Notes from the EUVE Science Archive
5.1 GO Data Release List for July and August 1994
5.2 Accessing the Archive
6. Job Listings at CEA
To comment on, make suggestions for, or request subscriptions to the EUVE
electronic newsletter, send e-mail to ceanews@cea.berkeley.edu (Internet).
1. EUVE User's Committee Extended Mission Proposal Presented at AAS
===================================================================
by Dr. Harry Shipman, EUVE User's Committee Chairman
The EUVE Users' Committee presented the current version of our proposal for
an EUVE extended mission at an AAS meeting. We held another lunchtime session
at the AAS meeting in Minneapolis. Even though the total number of people at
the whole meeting was smaller (it was held over Memorial Day Weekend), we still
had a standing-room only crowd at our session.
EUVE has, in fact, done a great deal of good science so far. The highlights
presented at Minneapolis included the discovery of high temperature, high
density plasma in cool star coronas, the factor of 30 excess EUV emission in
the B star Epsilon CMa, the EUV spectra from the inner parts of the accretion
region in cataclysmic variables (CV's), the asymmetry in the Io torus, the
discovery of helium on Mars, the ionization and structure of the local
interstellar medium (ISM), and the direct detection of the ionizing energy
source in the quasar Markarian 421.
The Users' Group will propose that the extended mission include a small
number of key projects which will occupy approximately 50% of the available
observing time, with the remaining available observing time being devoted to
GO projects of the sort that are currently being done. Our proposal will
describe a number of "candidate key projects." At the present time, these are:
(i) What energizes stellar coronae? EUVE will make repeated, carefully
planned observations of a selected sample of cool stars to answer this
important astrophysical question.
(ii) What happens at the innermost edge of the accreting region in CV's to
radiate away the gravitational energy? Continued observations of CV's,
done as Targets of Opportunity, may answer this question.
(iii) What is the structure of the local ISM, and how is it ionized? High
signal-to-noise observations of all the white dwarfs within several
tens of parsecs, observations of white dwarfs in the low-density tunnel
towards Beta and Epsilon CMa, and further observations of these critical
B stars will both tell us about ISM physics and will also provide
crucial information on the physics of the white dwarf and B stars.
(iv) What energizes the Io torus? Carefully planned, repeated maps can answer
this question.
(v) What does the EUV spectrum of quasars and active galactic nuclei (AGN)
look like and is it indeed where most of the energy comes out? Because
these targets are faint in the EUV, this set of observations is
extensive enough so that it is a key project.
EUVE users with other ideas for key projects, or ideas on how to describe these
key projects, are encouraged to come forward now. The EUVE Users' Group plans
to write a "white paper" on the extended mission early this summer.
The Users' Group has also discussed the issue of an unfunded GO program, and
has taken the position that funding of the GO program is a very important part
of getting the best science out of EUVE. However, we are not taking a hardline
position that if there's no funding for the GO program there should be no
extended mission. Please communicate with the users' group if you have any
thoughts on the extended mission or on the way that EUVE is operating.
2. Notes from the EUVE Guest Observer Program
=============================================
2.1 UCB Principal Investigator Guaranteed Time Observations (GTO)
-----------------------------------------------------------------
by Dr. Ron Oliversen, Deputy Project Scientist at GSFC
The U.C. Berkeley Principal Investigator is allocated 5% of the available
Episode 2 spectroscopy observing time under the terms of the agreement with
NASA regarding the construction and operation of the EUVE instruments. No
approved GTO target is allowed to duplicate any selected Episode 2 Guest
Observer Type 1 or Type 2 target. The GTO target has the same scheduling
priority as a GO Type 1 target. The GTO targets are listed below:
MKN279 200 ksec
GD50 70 ksec
PSRJ0108-1431 100 ksec
PSR0656+14 100 ksec
2.2 Target of Opportunity: VW Hyi
----------------------------------
by Anne Miller, EGO Center Technical Writer
The Spectrometers were used to observe the Target of Opportunity
(TOO) VW Hyi on 2 June for Guest Observer Dr. Christopher Mauche of
Lawrence Livermore Laboratory. VW Hyi, a CV, went into
double-outburst and was observed with up to 12 counts per second in
the deep survey Lexan/boron filter (70-180 A). The short- and
medium-wavelength detectors were used to record data during orbit day
and night; the deep survey detector was turned off for most of the
observation to prevent detector degradation. We hear that the data
for this source is outstanding.
2.3 Third EUVE GO NRA
---------------------
by Anne Miller, EGO Center Technical Writer
The third EUVE Guest Observer Program NASA Research Announcement (NRA) is
due to be released on 15 June. All of the Appendices to the Announcement of
Opportunity, including proposal forms and the the Guest Observer Handbook, will
be available from the CEA/EUVE anonymous ftp site (cea-ftp.cea.berkeley.edu)
after the Announcement has been mailed. The ftp site is most easily accessed
via the CEA HomePage on the World Wide Web:
http://cea-ftp.cea.berkeley.edu
After opening the HomePage, click on the icon labeled "ftp", then on the
directory "pub" and then "nra94". See the README files for more directions
and information. The World Wide Web can be accessed by a variety of client
programs, including NCSA Mosaic, the University of Kansas's LYNX, and others.
3. Abstracts of Recently *Accepted* EUVE Papers
===============================================
Included below are abstracts of EUVE-related papers recently *accepted*
for publication. GOs are encouraged to contribute *accepted* abstracts for
inclusion in future editions of this newsletter and for posting under the EGO
Center Mosaic "Home Page". All abstracts should be sent to
egoinfo@cea.berkeley.edu.
For those papers authored by CEA scientists, the EUVE publication number is
indicated. Unless otherwise noted, researchers may obtain (p)reprints of these
papers by sending an e-mail request along with the publication number(s) of
interest to pub@cea.berkeley.edu.
--------------------------------------------------------------
EXTREME ULTRAVIOLET SPECTROPHOTOMETRY OF HD15638 AND HR8210 (IK PEG)
M.A. Barstow, J.B. Holberg and and D.Koester
To appear in Monthly Notices of the Royal Astronomical Society
The main sequence stars HR8210 (IK Peg) and HD15638 have both been found
to have DA white dwarf companions by observations with the IUE satellite,
following their discovery as bright EUV sources by the ROSAT Wide Field Camera.
Accurate estimates of the temperature and surface gravity of each white dwarf,
based on the IUE data, were only possible when external constraints such as the
distance to the primary were applied. We present Extreme Ultraviolet Explorer
observations of each of these systems. From the resulting spectra we are able
to measure the temperature and surface gravity of each white dwarf with much
greater accuracy than possible with the earlier data. We demonstrate that the
white dwarf atmospheres have H layers sufficiently thick that they appear as
pure H DAs. There is no direct evidence for the presence of any additional
material in the photospheres that might have come from interactions with the
primaries. However, an inconsistency between the temperature of the HD15638
white dwarf obtained from the EUVE spectrum, with a pure H model atmosphere,
and that derived from the UV data might be explained by very small traces of
heavy element pollution. The distance we estimate for the white dwarf in
HR8210 is consistent with that to the A star, indicating that the A star has
not departed from single star evolution nor has it evolved away from the main
sequence. Measurements of the interstellar column densities yield HeI/HI
ratios consistent with cosmic abundances.
Key words: stars: binaries -- stars: atmospheres -- white dwarfs --
ultraviolet: stars - X-rays: stars.
--------------------------------------------------------------
FIRST MEASUREMENT OF HELIUM ON MARS: IMPLICATIONS FOR THE PROBLEM OF
RADIOGENIC GASES ON THE TERRESTRIAL PLANETS
V.A. Krasnopolsky, S. Bowyer, S. Chakrabarti, G.R. Gladstone, and J.S. McDonald
To appear in Icarus.
One hundred-eight photons of the Martian He 584 A airglow detected by the
Extreme Ultraviolet Explorer satellite during a two-day exposure (1993 January
22-23) correspond to the effective disk average intensity of 43 +/ -10 Rayleigh.
Radiative transfer calculations, using a model atmosphere appropriate to the
conditions of the observation and having an exospheric temperature of 210 +/- 20
K, result in a He mixing ratio of 1.1 +/- 0.4 ppm in the lower atmosphere.
Nonthermal escape of helium is due to electron impact ionization and pickup of
He^+ by the solar wind, to collisions with hot oxygen atoms, and to charge
exchange with molecular species with corresponding column loss rates of 1.4e5,
3e4, and 7e3 cm^(-2) s^(-1), respectively. The lifetime of helium on Mars is
5e4 yr, and it appears that outgassing processes have been rather strong on
Mars. The He outgassing rate, coupled with the (40)Ar atmospheric abundance
and with the K:U:Th ratio measured in the surface rocks, is used as input to
a single two-reservoir degassing model which presumes the loss of all argon
accumulated in the atmosphere during the first Gyr by large-scale impacts. The
model results in total planet mass ratios of 1e-5 g/g for K, 2.3e-9 g/g for U,
8.5e-9 g/g for Th, 4e-10 g/g for He, and 1.5e-9 g.g for (40)Ar. The predicted
radiogenic heat flux is 2 erg cm^(-2) s^(-1). Similar modeling for Venus
results in total planet mass ratios of 4.7e-5 g/g for K, 6.7e-9 g/g for U,
2.2e-8 g/g for Th, 1.3e-9 g.g for He, 6.7e-9 g/g for (40)Ar, and a radiogenic
heat flux of 15 erg cm^(-2) s^(-1). The implications of these results are
discussed.
--------------------------------------------------------------
4. NASA's EUVE Observatory Researchers Share a Ride
with Educators on the Information Superhighway
===================================================
by the CEA Educational Outreach Group
The Center for EUV Astrophysics (CEA) this month unveiled an innovative
resource for educators worldwide. The CEA Education Outreach Mosaic Page on
the Internet World Wide Web was opened to the public May 16. By participating
in CEA's Education Outreach programs, teachers from the K-12 community have
learned about Mosaic and the rich resources available on the "Information
Superhighway."
"One of CEA's primary goals is to use the EUVE satellite mission's exciting
scientific discoveries as a tool for educational outreach involving K-12
teachers, students, and the general public," explains Dr. Isabel Hawkins, CEA
education outreach coordinator.
Hawkins and Nellie Levandovsky, a physics teacher at San Francisco's Galileo
High School, presented papers describing an innovative class for teachers at a
special session of the American Astronomical Society Meeting in Minneapolis.
Due to advances in communication and hardware technology, teachers, students,
and the general public now have an opportunity to access Mosaic from schools
and homes using the "Lynx" system. The Mosaic Universal Resource Locator
address on Internet for the CEA/EUVE Home Page is
http://cea-ftp.cea.berkeley.edu/HomePage.html.
A key element of CEA's Education Outreach Program focused on a semester-long
course for K-12 teachers entitled ASTRO 650: "Satellite Mission Operations."
This class, a collaboration between CEA and San Francisco State University,
was funded by a NASA Astrophysics Division Grant Supplement for Education
(AGSE), a program headed by Drs. Jeff Rosendhal and Cheri Morrow of NASA
Headquarters Astrophysics Division.
During the last third of the semester, the course instructor, CEA astronomer
Hawkins assisted the teachers in designing lesson plans based on the EUVE and
other NASA satellite missions as Mosaic pages which will be available on the
Internet and accessible to educators worldwide.
In keeping with NASA Administrator Daniel Goldin's directive that the space
agency's employees become involved in education outreach activities, the CEA
EUVE Education Outreach Mosaic page highlights CEA's programs, including K-12
school outreach, public events, and undergraduate enrichment.
"FaxFriends" a pilot collaboration between CEA and the diverse Lodi Unified
School District, allows teachers and students to ask space science and astronomy
questions via facsimile transmission. CEA scientists and other staff members
make related information from EUVE and other NASA missions available. CEA has
introduced the program "FaxAmigos" which allows Spanish-speaking students to
participate in this program and read previously-asked questions that have been
translated into Spanish on CEA's Mosaic page.
Fernando Astorga, Jennifer Moriarta, and Rachel Brandstetter are some of
CEA's undergraduate student employees who will spend the summer at the Jet
Propulsion Laboratory in Pasadena, CA, or at NASA/Ames in Mountain View, CA,
as part of internship exchange programs. These students will be investigating
artificial intelligence software, implementing satellite ground control stations
similar to backyard television receiver dishes, and assisting in the development
of artificial intelligence applications for science planning. All of these
techniques will be applied to the EUVE satellite as a test-bed for innovative
and low-cost approaches to mission operations.
5. Notes from the EUVE Science Archive
======================================
by Brett A. Stroozas, DASS/Archive Manager
5.1 GO Data Release List for July and August 1994
-------------------------------------------------
The table below lists the GO observations which become public on 1 July
and 1 August 1994. For each entry is given the target name, the approximate
exposure time in kiloseconds, the GMT start and end date(s) for the observation,
the spectral type of the target, an indication of which (if any) EUVE CD-ROM
on which the observation appears, and the data identification code. All public
data sets may be ordered from the archive via CEA electronic or postal mail.
Please be sure to include in your order the DataID(s) of interest.
The data rights policy on GO observations states that the GO has proprietary
rights to the data for one year from the date (s)he receives it. It is often
the case that long observations are broken up over many months; e.g. an
observation approved for 60 ksec may actually be observed for 10 ksec one
month, 20 ksec the next and 30 ksec three months later. In such cases the
one-year proprietary period begins after (s)he receives the final piece of
the complete observation. An exception to the one-year rule occurs when the
target was designated for calibration purposes. At the discretion of the
EUVE Project Scientist, calibration observations be released early (usually
by only a few months), before the expiration of the normal one-year period.
In the list below, calibration targets have been marked with a "*".
=====================================================================
Target ~Exp Observation Date(s) SpT CD-ROM DataID
Name (ksec) Start End
=====================================================================
Data Sets Available 1 July 1994:
ALPHA_VIR 71 9 May 1993 - 12 May 1993 B1IV ---- go0061
BETA_CEN 94 24 May 1993 - 28 May 1993 B1II ---- go0062
DELTA_CEN 6 18 Apr 1993 - 18 Apr 1993 B2IV ---- go0059
DELTA_CEN 30 1 Apr 1993 - 2 Apr 1993 B2IV ---- go0058
ETA_CEN 150 4 May 1993 - 9 May 1993 B1.5 ---- go0064
FEIGE24 23 25 Nov 1993 - 26 Nov 1993 WD ---- go0076 *
FEIGE24 26 15 Oct 1993 - 16 Oct 1993 WD ---- go0072 *
G191-B2B 62 28 Oct 1993 - 30 Oct 1993 WD ---- go0073 *
HD131156 74 2 Apr 1993 - 5 Apr 1993 G+K ---- go0052
HS1234+4811 86 19 Feb 1993 - 22 Feb 1993 WD ---- go0053
II_PEG 108 1 Oct 1993 - 5 Oct 1993 K1 ---- go0070 *
LAMBDA_SCO 99 2 Jun 1993 - 6 Jun 1993 B1V ---- go0068
MCT0455-2812 52 14 Nov 1993 - 16 Nov 1993 WD ---- go0074 *
MK478 65 16 Apr 1993 - 18 Apr 1993 AGN ---- go0055
MK478 66 14 Apr 1993 - 16 Apr 1993 AGN ---- go0056
MK478 70 11 Apr 1993 - 14 Apr 1993 AGN ---- go0057
MR_SER 44 1 Jun 1993 - 2 Jun 1993 CV ---- go0067
MU_CEN 39 7 Apr 1993 - 9 Apr 1993 B2IV ---- go0054
NGC5548 351 10 Mar 1993 - 23 Mar 1993 AGN ---- go0060
PG1159-035 37 6 Apr 1993 - 7 Apr 1993 WD ---- go0065
PROXIMA_CEN 86 21 May 1993 - 24 May 1993 M5.5 ---- go0063
RE1849-033 28 6 Jun 1993 - 7 Jun 1993 NOID ---- go0069
SIRIUS_B 45 22 Nov 1993 - 23 Nov 1993 WD ---- go0075 *
V834_CEN 41 28 May 1993 - 29 May 1993 CV ---- go0066
WD2309+105 27 5 Oct 1993 - 6 Oct 1993 WD ---- go0071 *
Data Sets Available 1 Aug 1994:
ALTAIR 88 27 Jun 1993 - 30 Jun 1993 A7V ---- go0077
G191-B2B 25 7 Dec 1993 - 8 Dec 1993 WD ---- go0084 *
H1504+65 68 5 Dec 1993 - 7 Dec 1993 WD ---- go0085 *
MOON 1 9 Apr 1993 - 9 Apr 1993 SS ---- go0083
MOON 4 5 Apr 1993 - 5 Apr 1993 SS ---- go0082
NGC5548 65 12 May 1993 - 14 May 1993 AGN ---- go0081
NGC5548 75 26 Apr 1993 - 29 Apr 1993 AGN ---- go0078
NGC5548 75 29 Apr 1993 - 1 May 1993 AGN ---- go0079
NGC5548 75 1 May 1993 - 4 May 1993 AGN ---- go0080
=====================================================================
5.2 Accessing the Archive
-------------------------
Listed below are the various methods for accessing EUVE archival material:
o CEA World Wide Web URL:
http://cea-ftp.cea.berkeley.edu (Mosaic/lynx remotely)
telnet cea-ftp.cea.berkeley.edu 200 (lynx locally at CEA)
o NASA's Astrophysics Data System (general and account information):
http://adswww.colorado.edu/adswww/adshomepg.html (Mosaic/lynx)
ads@cuads.colorado.edu
o CD-ROM Series: Volumes 1.1, 2.1, and 2.2 (seven separate CDs) available
o e-mail: archive@cea.berkeley.edu
(include word "help" -- quotes omitted -- as body of message)
o anonymous FTP (or gopher): cea-ftp.cea.berkeley.edu
o EUVE Electronic Newsletters: ceanews@cea.berkeley.edu (to subscribe)
o Postal Mail:
The EUVE Public Science Archive
Center for EUV Astrophysics
2150 Kittredge St.
Berkeley, CA 94720
510-642-3032 (voice) or 510-643-5660 (fax)
archive@cea.berkeley.edu
6. Job Listings at CEA
======================
by Cathie Jones, CEA Personnel Manager
CEA is currently accepting applications for the following job positions.
--------------------------------------------------------------
Postgraduate/Assistant Research (depending on experience)
University of California
Center for EUV Astrophysics
Attn: Cathie Jones (Personnel)
2150 Kittredge St.
Berkeley, CA 94720
The Extreme Ultraviolet Explorer (EUVE) Program at the Center for EUV
Astrophysics, of the University of California, Berkeley, has opening for a
Research Scientist. Successful applicant will support the acquisition, and
reduction of pointed data from the EUVE satellite. Duties will include
monitoring the progress of observation scheduling and data acquisition,
pipeline processing and data reductions and analysis. The researcher will
assist Guest Investigators, through the Guest Observer program and the EUVE
Archive program, in understanding the performance of the EUVE scientific
instruments as well as provide scientific advice regarding use of the EUVE
spectrometer analysis packages, written primarily in IRAF. Additional duties
will involve assisting in the development of complex data analysis algorithms
and models, to be made available to the Guest Investigator community in the
EUVE IRAF packages and EUVE public archive.
The work will be performed under the direction of the EUVE Science Support
Project Manager, and will interact with the associated science and programming
staff in the EUVE Public Archive and Guest Observer Center. A fraction of time
(10%) will be available to allow pursuit of independent research.
Applicants must have a Ph.D. in astronomy, physics, or a related field.
Experience supporting NASA Archival Research, Guest Observer, and Guest
Investigator programs required. Experience in satellite or ground-based
astronomical data analysis and the ability to carry out research in the field
of EUV astronomy is highly desirable. Experience with IRAF would be most
helpful.
Applications should include a curriculum vitae, bibliography and three
letters of recommendation and should be submitted by April 30, 1994. EOE/AAE.
--------------------------------------------------------------
Staff Research Associate I
University of California
Center for EUV Astrophysics
Attn: Cathie Jones (Personnel)
2150 Kittredge St.
Berkeley, CA 94720
The Center for EUV Astrophysics (CEA) seeks candidates for the position of
Staff Research Associate (SRA) I. The successful candidate will support the
Science Archive for the Extreme Ultraviolet Explorer (EUVE) Satellite
Project. The SRA will handle Archive correspondence (e.g. answering questions
and filling order requests for data), participate in the organization and
maintenance of the Archive FTP and Mosaic sites, assist in the processing and
analysis of EUVE data sets to support public data releases, participate in the
production of EUVE CD-ROMs, and assist with activities (e.g. database and
service development, testing and installation) for the CEA node of NASA's
Astrophysics Data System (ADS). Other duties include documentation of work
results and support of Archive publications.
Required qualifications include a background in Astronomy, Physics, or other
applicable science, demonstrated knowledge of general astronomical data
reduction techniques, experience using astronomical data analysis packages
(especially IRAF), experience with shell scripts (C or Bourne) and the UNIX
operating system, strong organizational skills and attention to detail, and
excellent verbal and written communication skills. Desired qualifications
include previous experience with ADS, an ``operations-oriented'' (versus
``research-oriented'') work style, and experience programming in the C and/or
FORTRAN languages.
Applications should include a curriculum vitae and the names, addresses,
and phone numbers of three people whom we can contact for references.
The University of California is an Equal Opportunity Affirmative Action
Employer.
---------------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme Ultraviolet
Astrophysics, University of California, Berkeley, CA 94720, USA. The opinions
expressed are those of the authors. EUVE Principal Investigators and Newsletter
Publishers: Drs. R.F. Malina and C.S. Bowyer. EGO and Archive Science Manger:
C.A. Christian. Archive Manager and Newsletter Editor: B.A. Stroozas. Funded
by NASA contracts NAS5-30180 and NAS5-29298. Send newsletter correspondence
to: ceanews@cea.berkeley.edu. The EUVE project is managed by NASA's GSFC.
The GSFC Project Manager: Paul Pashby, Project Scientist: Dr. Yoji Kondo,
Deputy Project Scientist: Dr. Ronald Oliversen. NASA HQ Program Scientist:
Dr. Robert Stachnik, Deputy Program Scientist: Dr. D. Buzasi, Program Manager:
Dr. G. Riegler. GSFC Project Operations Director: Mr. Kevin Hartnett.
Information on the EUVE Guest Observer Program is available from: Dr. Y.
Kondo, Mail Code 684, GSFC, Greenbelt, MD 20771 at (301) 286-6247 or e-mail to
euve@stars.span.nasa.gov.
END-----------EUVE------------ELECTRONIC---------------NEWS-------------END
|
| 770.39 | July 13 | MTWAIN::KLAES | Houston, Tranquility Base here... | Wed Jul 20 1994 16:44 | 487 |
| From: VERGA::US4RMC::"ceanews@cea.Berkeley.EDU" "EUVE Electronic Newsletter
distribution" 14-JUL-1994 00:36:39.83
To: euvenews@cea.Berkeley.EDU
CC:
Subj: EUVE Electronic Newsletter
EEEEEEEEEEE U U V V EEEEEEEEEEE
E U U V V E
E U U V V E
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E U U V V E
E U U V V E
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
---------------------------------------------------------------------------
Vol 4, No. 7 13 Jul 1994 ISSN 1065-3597
---------------------------------------------------------------------------
Notes from the Editor
=====================
by Brett A. Stroozas, Data Analysis Support Staff (DASS)
and Archive Manager
Welcome to the electronic newsletter for NASA's Extreme Ultraviolet Explorer
(EUVE) satellite, which is compiled and published monthly by the EUVE Science
Archive group at the Center for EUV Astrophysics (CEA) in Berkeley, CA. The
EUVE observatory performed well throughout the month of June, completing
observations of the following Guest Observer (GO) targets: 3C273 (a Quasar),
Comet Mueller, Jupiter (prior to the comet impact event), LVC 88+36 (an HI
filament), SAO 188337 (a B star), SS Cyg (dwarf nova), V1974 Cyg (Nova Cyg
1992), VW Hyi (cataclysmic variable), and zeta Oph (an O star). EUVE also
conducted some engineering test of its star trackers.
The contents of this issue of the EUVE electronic newsletter are as follows:
1. EUVE Third Episode GO Proposal Deadline
2. The EUVE Comet Impact Event: Cosmic Collisions
3. Abstracts of Recently *Accepted* EUVE Papers
4. Notes from the EUVE Science Archive
4.1 GO Data Release List for August and September 1994
4.2 New Documentation and Services
4.3 Accessing the Archive
5. Job Listings at CEA
To comment on, make suggestions for, or request subscriptions to the EUVE
electronic newsletter, send e-mail to ceanews@cea.berkeley.edu (Internet).
1. EUVE Third Episode GO Proposal Deadline
==========================================
by Dr. Ron Oliversen, EUVE Deputy Project Scientist at GSFC
The EUVE 3rd Episode NASA Research Announcement (NRA) release date has been
delayed. We expect, according to our current best estimates, the EUVE NRA will
be released on 8 August with a GO proposal due date of 7 October. Note, this
would be a 60-day instead of the usual 90-day notice between date of release
and the proposal deadline. All NRA appendices will be available electronically
or via hardcopy at the time of the NRA release. Specific details will be
available in next month's newsletter.
2. The EUVE Comet Impact Event: Cosmic Collisions
==================================================
*******************************************************
U.C. Berkeley's
NASA Extreme Ultraviolet Explorer satellite project
and
the Exploratorium
present
-------------------------------------
C O S M I C C O L L I S I O N S :
A Celebration of the Impending Impact
of Comet Shoemaker-Levy 9 on Jupiter
-------------------------------------
Thursday, July 14, 1994
6:30 pm - 10:00 pm
Palace of Fine Arts Theater
San Francisco
*******************************************************
Join Professor Timothy Ferris & guest speakers:
*Dr. Marcia Neugebauer
Comet Specialist, NASA's Jet Propulsion Laboratory
*Dr. Jere Lipps
Director, University of California Museum of Paleontology
*Dr. Randy Gladstone
Planetary Scientist, Southwest Research Institute,
Extreme Ultraviolet Explorer Guest Observer
*Kevin Anderson
Science Fiction Writer,
author of the current New York Times Best Seller
"STAR WARS; Dark Apprentice, Volume 2 of the Jedi Academy Trilogy"
*Poul Anderson
Science Fiction Writer,
author of "Harvest of Stars" and winner of seven Hugo and
three Nebula Awards.
--------------------------------------------------------------
The evening will highlight the upcoming comet impact, other comet
collisions in the past, including the comet theory of dinosaur mass
extinction, plus the role of cosmic collisions in popular culture.
EXHIBITS AND BOOTHS - doors open at 6:30 p.m. Tentatively Scheduled
Participants to include:
* Center for Extreme Ultraviolet Astrophysics
* Exploratorium
* Another Change of Hobbit
* Bay Area Musician's Forum
* Hearts of Space Records
* The Nature Company
* Leonardo/International Society of Arts, Sciences, and Technology
* Wired magazine
* YLEM: Artists Using Science and Technology
TALKS begin promptly at 7:30 p.m.
*************************************************************************
Both Kevin Anderson and Poul Anderson will be available for BOOK SIGNINGS.
*************************************************************************
General Admission ........... $10.00
Exploratorium Members ....... $ 8.00
Thursday, July 14, 1994, 6:30 pm - 10:00 pm,
Palace of Fine Arts, San Francisco
For tickets and further information, please contact CITY BOX OFFICE
- (415) 392-4400
*******************
TICKETS NOW ON SALE
*******************
3. Abstracts of Recently *Accepted* EUVE Papers
===============================================
Included below are abstracts of EUVE-related papers recently *accepted*
for publication. GOs are encouraged to contribute *accepted* abstracts for
inclusion in future editions of this newsletter and for posting under the EGO
Center Mosaic "Home Page". All abstracts should be sent to
egoinfo@cea.berkeley.edu.
For those papers authored by CEA scientists, the EUVE publication number is
indicated. Unless otherwise noted, researchers may obtain preprints of these
papers by sending an e-mail request along with the publication number(s) of
interest to pub@cea.berkeley.edu.
--------------------------------------------------------------
TWO-SAMPLE DISCRIMINATION OF POISSON MEANS
M. Lampton
To appear in The Astrophysical Journal [CEA publication #590]
This paper presents a statistical test for detecting significant differences
between two random count accumulations. The null hypothesis is that the two
samples share a common random arrival process with a mean count proportional
to each sample's exposure. The model represents the partition of N total
events into two counts, A and B, as a sequence of N independent Bernoulli
trials whose partition fraction, f, is determined by the ratio of the exposures
of A and B. The detection of a significant difference is claimed when the
background (null) hypothesis is rejected, which occurs when the observed sample
falls in a critical region of (A, B) space. The critical region depends on f
and the desired significance level, alpha. The model correctly takes into
account the fluctuations in both the signal and the background data, including
the important case of small numbers of counts in the signal, the background,
or both. The significance can be exactly determined from the cumulative
binomial distribution, which in turn can be inverted to determine the critical
A(B) or B(A) contour. This paper gives efficient implementations of these
tests, based on lookup tables. Applications include the detection of
clustering of astronomical objects, the detection of faint emission or
absorption lines in photon-limited spectroscopy, the detection of faint
emitters or absorbers in photon-limited imaging, and dosimetry.
--------------------------------------------------------------
SPECTROSCOPIC, ORBITAL AND PHYSICAL PROPERTIES OF THE BINARY FEIGE 24 AND
DETECTION OF TRANSIENT HEII ABSORPTION IN THE SYSTEM
S. Vennes and J.R. Thorstensen
To appear in The Astronomical Journal [CEA publication #591]
We have obtained new high-dispersion optical spectroscopy at Kitt Peak
National Observatory (KPNO) and new International Ultraviolet Explorer (IUE)
spectroscopy of the white dwarf + red dwarf binary system Feige 24 (P =
4.23160 d). The optical range shows a composite DA+dM spectrum, together
with HI Balmer and HeI emission. The orbital phase dependence of the emission
shows that it results from extreme ultraviolet (EUV) light reprocessing in
the red dwarf upper atmosphere. The system is close enough and hot enough
to show this reprocessing signature only recently emerged from common-envelope
evolution. The ultraviolet spectrum exclusively emanates from the white
dwarf, traced by ultraviolet FeV lines. Combining these measurements, we
refined the orbital parameters presented by Vennes et al. (1991), and we
confirmed that the white dwarf gravitational redshift is exceptionally small
with 9 +/- 2 km/s. From this we deduced that the interior is either pure
helium or carbon with a thick hydrogen layer (=1e-4 M_solar), and we derived,
for the combined interior compositions, a white dwarf mass and radius of
M_WD = 0.44-0.50 M_solar and R_WD = 0.028-0.036 R_solar. We suggest that
Feige 24 could be a typical case of close binary evolution leading to the
formation of a low-mass helium white dwarf. The mass of the red dwarf and
the inclination of the system naturally follow: M_dM = 0.26-0.33 M_solar,
i >= 75 deg. High-dispersion H_alpha line profiles are asymmetrical, strongly
enhanced toward the blue, suggesting a moving atmosphere possibly linked to
a mass loss rate of 1e-10 M_solar/yr. The IUE spectra taken when the system
is near inferior conjunction show strong HeII 1640 A absorption. The profile
is highly variable in width (maximum FWHM = 90 km/s) and intensity. Because
it is correlated with the passage of the white dwarf at inferior conjunction,
the absorption may occur in some foreground plasma emanated by the red dwarf
and accumulating near a Lagrangian point or, alternatively, it may originate
in an accretion spot on the white dwarf surface co-aligned with the major
orbital axis. Either way, the HeII detection may imply a substantial mass
loss from the red dwarf with a corollary reclassification of Feige 24 as a
mixed He/H DAO white dwarf resulting from accretion of secondary mass-loss
material. Feige 24 is the prototype of a secondary and a hot H-rich white
dwarf; the class is characterized by optical (4686 A) and ultraviolet (1640 A)
photospheric HeII absorption, circumstellar CIV 1550 A absorption, and by the
presence of EUV-induced, phase-dependent Balmer fluorescence. These young
systems present the best opportunity to constrain theory of common-envelope
evolution.
Subject Headings: stars: binaries -- late-type -- white dwarfs -- individual
(Feige 24) -- ultraviolet: stars
--------------------------------------------------------------
DISCOVERY OF A NEW WHITE DWARF IN A BINARY SYSTEM (EUVE 0720-317) IN THE
EXTREME ULTRAVIOLET EXPLORER SURVEY AND IMPLICATIONS FOR THE LATE STAGES
OF STELLAR EVOLUTION
S. Vennes and J.R. Thorstensen
To appear in The Astrophysical Journal Letters [CEA publication #592]
A new pre-cataclysmic binary is identified in th Extreme Ultraviolet
Explorer (EUVE) all-sky survey. The bright source EUVE 0720-317 shows a
hot hydrogen-rich white dwarf optical continuum with overlying narrow
Balmer-line emission. Using high signal-to-noise spectroscopy in the
4100-6700 A range we identify a late-type companion and find a 1.3 d
periodic modulation in the emission-line velocities and strengths. We
determine the components' spectral types (DAO and dM0-2), orbital velocities
(gamma = 15 +/- 12 km/s). A first estimate of the white dwarf gravitational
redshift, gamma_g = 45 +/- 20 km/s, and theoretical mass-radius relationships
imply R_DAO = 0.010-0.016 R_solar and M_DAO = 0.55-0.90 M_solar. The orbital
inclination is therefore i >= 52 deg, consistent with the large amplitude
variations found in H_alpha equivalent widths that imply i >= 42 deg. We
show that the discovery of new close WD+MS binary systems in EUV sky surveys
has important implications for theory of common-envelope evolution, in
particular for the predicted close binary birthrate and orbital and stellar
parameters.
Subject headings: stars: binaries -- late-type -- white dwarfs -- individual
(EUVE 0720-317) -- ultraviolet: stars
--------------------------------------------------------------
SERENDIPITOUS EUV SOURCES DETECTED DURING THE FIRST YEAR OF THE EXTREME
ULTRAVIOLET EXPLORER RIGHT ANGLE PROGRAM
K. McDonald, N. Craig, M.M. Sirk, J.J. Drake, A. Fruscione, J.V. Vallerga,
and R.F. Malina
To appear in The Astronomical Journal [CEA publication #593]
We report the detection of 114 extreme ultraviolet (EUV; 58-740 A) sources,
of which 99 are new serendipitous sources, based on observations made with the
imaging telescopes on board the Extreme Ultraviolet Explorer (EUVE) during the
Right Angle Program (RAP). These data were obtained using the survey scanners
and the Deep Survey instrument during the first year of the spectroscopic guest
observer phase of the mission, from January 1993 to January 1994. The data
set consists of 162 discrete pointings whose exposure times are typically two
orders of magnitude longer than the average exposure times during the EUVE
all-sky survey. Based on these results, we can expect that EUVE will
serendipitously detect approximately 100 new EUV sources per year, or about
one new EUV source per 10 square degrees, during the guest observer phase of
the EUVE mission. New EUV sources of note include one B star and three
extragalactic objects. The B star (HR 2875, EUVE J0729-38.7) is detected in
both the Lexan/B (~100 A) and Al/Ti/C (~200 A) bandpasses, and the detection
is shown not to be a result of UV leaks. We suggest that we are detecting
EUV and/or soft X-rays from a companion to the B star. Three sources, EUVE
J2132+10.1, EUVE J2343-14.9, and EUVE J2359-30.6 are identified as the active
galactic nuclei MKN 1513, MS2340.9-1511, and 1H2354-315, respectively.
--------------------------------------------------------------
4. Notes from the EUVE Science Archive
======================================
by Brett A. Stroozas, DASS/Archive Manager
4.1 GO Data Release List for August and September 1994
------------------------------------------------------
The table below lists the GO observations which become public on 1 August
and 1 September 1994. For each entry is given the target name, the approximate
exposure time in kiloseconds, the GMT start and end date(s) for the observation,
the spectral type of the target, an indication of which (if any) EUVE CD-ROM
on which the observation appears, and the data identification code. All public
data sets may be ordered from the archive via CEA electronic (e.g., "mailorder
go0001") or postal mail. Please be sure to include in your order the DataID(s)
of interest.
The data rights policy on GO observations states that the GO has proprietary
rights to the data for one year from the date (s)he receives it. It is often
the case that long observations are broken up over many months; e.g. an
observation approved for 60 ksec may actually be observed for 10 ksec one
month, 20 ksec the next and 30 ksec three months later. In such cases the
one-year proprietary period begins after the GO receives the final piece of
the complete observation. An exception to the one-year rule occurs when the
target was designated for calibration purposes. At the discretion of the
EUVE Project Scientist, calibration observations may be released before the
expiration of the normal one-year period (usually by only a few months). In
the list below, calibration targets have been marked with a "*".
=====================================================================
Target ~Exp Observation Date(s) SpT CD-ROM DataID
Name (ksec) Start End
=====================================================================
Data Sets Available 1 Aug 1994:
ALTAIR 88 27 Jun 1993 - 30 Jun 1993 A7V ---- go0077
G191-B2B 25 7 Dec 1993 - 8 Dec 1993 WD ---- go0084 *
H1504+65 68 5 Dec 1993 - 7 Dec 1993 WD ---- go0085 *
MOON 4 5 Apr 1993 - 5 Apr 1993 SS ---- go0082
MOON 1 9 Apr 1993 - 9 Apr 1993 SS ---- go0083
NGC5548 75 26 Apr 1993 - 29 Apr 1993 AGN ---- go0078
NGC5548 75 29 Apr 1993 - 1 May 1993 AGN ---- go0079
NGC5548 75 1 May 1993 - 4 May 1993 AGN ---- go0080
NGC5548 65 12 May 1993 - 14 May 1993 AGN ---- go0081
Data Sets Available 1 Sep 1994:
HD149499_B 99 23 Jun 1993 - 27 Jun 1993 K0V ---- go0086
HD165341 86 2 Jul 1993 - 5 Jul 1993 K0V ---- go0087
HD223816 67 6 Aug 1993 - 8 Aug 1993 F5IV ---- go0091
HR8210 98 23 Jul 1993 - 27 Jul 1993 A8m ---- go0090
HS1234+4811 86 19 Feb 1993 - 22 Feb 1993 WD ---- go0053
MCT2331-4731 57 8 Aug 1993 - 10 Aug 1993 WD ---- go0089
MOON 2 30 Jun 1993 - 30 Jun 1993 SS ---- go0088
SS_CYG 187 17 Aug 1993 - 23 Aug 1993 A1pe ---- go0092
=====================================================================
4.2 New Documentation and Services
----------------------------------
The Archive is pleased to announce some newly released EUVE material. The
following are now available via the World Wide Web from the CEA Uniform
Resource Locator (URL; http://cea-ftp.cea.berkeley.edu):
* The Archive "Home Page" has been completely revamped, providing users with
a much friendlier (and less wordy) graphical point-and-click interface.
* A spectral data browser has been implemented which allows users to browse
and retrieve EUVE 1-d FITS spectra (see the "Spectra" listing under "Data").
* New forms for ordering EUVE CD-ROMs and public full GO data sets are now
available. Archival researchers may simply fill out a form requesting the
DataID(s) of interest and these requests will be forwarded and processed
by the Archive group at CEA.
* Additional EUVE-related publications have been added on-line. The long-term
goal is to make available the complete EUVE bibliography. The Archive
is continuously hooking in published papers so that researchers may access
them -- text, figures and tables -- on-line (see the "EUVE Bibliography"
listing under "Documentation").
In addition, The First EUVE Source Catalog (FESC; Bowyer, et al. 1994) is
now available from the CEA node of NASA's Astrophysics Data System (ADS). This
catalog, called "euve_cat1" and listed under the "Data:Catalogs" menu in ADS,
contains the detected EUV sources from the all-sky and deep surveys (tables 1
and 2 from the FESC paper). For completeness, a supplemental catalog will soon
be available which contains those sources from the Bright Source List (Malina,
et al., 1994) which did not meet the more stringent detection criteria set
forth in the FESC.
4.3 Accessing the Archive
-------------------------
Listed below are the various methods for accessing EUVE archival material:
o CEA World Wide Web URL:
http://cea-ftp.cea.berkeley.edu (Mosaic/lynx remotely)
telnet cea-ftp.cea.berkeley.edu 200 (lynx locally at CEA)
o NASA's Astrophysics Data System (general and account information):
http://adswww.colorado.edu/adswww/adshomepg.html (Mosaic/lynx)
ads@cuads.colorado.edu
o CD-ROM Series: Volumes 1.1, 2.1, and 2.2 (seven separate CDs) available
o e-mail: archive@cea.berkeley.edu
(include word "help" -- quotes omitted -- as body of message)
o anonymous FTP (or gopher): cea-ftp.cea.berkeley.edu
o EUVE Electronic Newsletters: ceanews@cea.berkeley.edu (to subscribe)
o Postal Mail:
The EUVE Public Science Archive
Center for EUV Astrophysics
2150 Kittredge St.
Berkeley, CA 94720
510-642-3032 (voice) or 510-643-5660 (fax)
archive@cea.berkeley.edu
5. Job Listings at CEA
======================
by Cathie Jones, CEA Personnel Manager
CEA is currently accepting applications for the following job positions.
--------------------------------------------------------------
Postgraduate/Assistant Research (depending on experience)
University of California
Center for EUV Astrophysics
Attn: Cathie Jones (Personnel)
2150 Kittredge St.
Berkeley, CA 94720
The Extreme Ultraviolet Explorer (EUVE) Program at the Center for EUV
Astrophysics, of the University of California, Berkeley, has opening for a
Research Scientist. Successful applicant will support the acquisition, and
reduction of pointed data from the EUVE satellite. Duties will include
monitoring the progress of observation scheduling and data acquisition,
pipeline processing and data reductions and analysis. The researcher will
assist Guest Investigators, through the Guest Observer program and the EUVE
Archive program, in understanding the performance of the EUVE scientific
instruments as well as provide scientific advice regarding use of the EUVE
spectrometer analysis packages, written primarily in IRAF. Additional duties
will involve assisting in the development of complex data analysis algorithms
and models, to be made available to the Guest Investigator community in the
EUVE IRAF packages and EUVE public archive.
The work will be performed under the direction of the EUVE Science Support
Project Manager, and will interact with the associated science and programming
staff in the EUVE Public Archive and Guest Observer Center. A fraction of time
(10%) will be available to allow pursuit of independent research.
Applicants must have a Ph.D. in astronomy, physics, or a related field.
Experience supporting NASA Archival Research, Guest Observer, and Guest
Investigator programs required. Experience in satellite or ground-based
astronomical data analysis and the ability to carry out research in the field
of EUV astronomy is highly desirable. Experience with IRAF would be most
helpful.
Applications should include a curriculum vitae, bibliography and three
letters of recommendation and should be submitted by April 30, 1994. EOE/AAE.
--------------------------------------------------------------
Staff Research Associate I
University of California
Center for EUV Astrophysics
Attn: Cathie Jones (Personnel)
2150 Kittredge St.
Berkeley, CA 94720
The Center for EUV Astrophysics (CEA) seeks candidates for the position of
Staff Research Associate (SRA) I. The successful candidate will support the
Science Archive for the Extreme Ultraviolet Explorer (EUVE) Satellite
Project. The SRA will handle Archive correspondence (e.g. answering questions
and filling order requests for data), participate in the organization and
maintenance of the Archive FTP and Mosaic sites, assist in the processing and
analysis of EUVE data sets to support public data releases, participate in the
production of EUVE CD-ROMs, and assist with activities (e.g. database and
service development, testing and installation) for the CEA node of NASA's
Astrophysics Data System (ADS). Other duties include documentation of work
results and support of Archive publications.
Required qualifications include a background in Astronomy, Physics, or other
applicable science, demonstrated knowledge of general astronomical data
reduction techniques, experience using astronomical data analysis packages
(especially IRAF), experience with shell scripts (C or Bourne) and the UNIX
operating system, strong organizational skills and attention to detail, and
excellent verbal and written communication skills. Desired qualifications
include previous experience with ADS, an "operations-oriented" (versus
"research-oriented") work style, and experience programming in the C and/or
FORTRAN languages.
Applications should include a curriculum vitae and the names, addresses,
and phone numbers of three people whom we can contact for references.
The University of California is an Equal Opportunity Affirmative Action
Employer.
--------------------------------------------------------------
REFERENCES
Bowyer, S., et al., The First EUVE Source Catalog, Astrophysical Journal
Supplement, 1994 (in press)
Malina, R.F., et al., The Extreme Ultraviolet Explorer Bright Source List,
Astronomical Journal, 107(2), 751-764, 1994
---------------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme Ultraviolet
Astrophysics, University of California, Berkeley, CA 94720, USA. The opinions
expressed are those of the authors. EUVE Principal Investigators and Newsletter
Publishers: Drs. R.F. Malina and C.S. Bowyer. EGO and Archive Science Manger:
C.A. Christian. Archive Manager and Newsletter Editor: B.A. Stroozas. Funded
by NASA contracts NAS5-30180 and NAS5-29298. Send newsletter correspondence
to: ceanews@cea.berkeley.edu. The EUVE project is managed by NASA's GSFC.
The GSFC Project Manager: Paul Pashby, Project Scientist: Dr. Yoji Kondo,
Deputy Project Scientist: Dr. Ronald Oliversen. NASA HQ Program Scientist:
Dr. Robert Stachnik, Program Manager: Dr. G. Riegler. GSFC Project Operations
Director: Mr. Kevin Hartnett. Information on the EUVE Guest Observer Program
is available from: Dr. Y. Kondo, Mail Code 684, GSFC, Greenbelt, MD 20771 at
(301) 286-6247 or e-mail to euve@stars.span.nasa.gov.
END-----------EUVE------------ELECTRONIC---------------NEWS-------------END
% ====== Internet headers and postmarks (see DECWRL::GATEWAY.DOC) ======
% Date: Wed, 13 Jul 1994 20:25:13 -0700
% From: EUVE Electronic Newsletter distribution <ceanews@cea.Berkeley.EDU>
% Message-Id: <199407140325.UAA20149@imperial.cea.berkeley.edu>
% To: euvenews@cea.Berkeley.EDU
% Subject: EUVE Electronic Newsletter
|
| 770.40 | August 10 | MTWAIN::KLAES | No Guts, No Galaxy | Thu Aug 11 1994 20:35 | 344 |
| From: VERGA::US4RMC::"ceanews@cea.Berkeley.EDU" "EUVE Electronic Newsletter
distribution" 10-AUG-1994 21:57:53.46
To: euvenews@cea.Berkeley.EDU
CC:
Subj: EUVE Electronic Newsletter
EEEEEEEEEEE U U V V EEEEEEEEEEE
E U U V V E
E U U V V E
EEEEEEE U U V V EEEEEEE
E U U V V E
E U U V V E
EEEEEEEEEEE UUUUU V EEEEEEEEEEE
---------------------------------------------------------------------------
ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
---------------------------------------------------------------------------
Vol 4, No. 8 10 Aug 1994 ISSN 1065-3597
---------------------------------------------------------------------------
Notes from the Editor
=====================
by Brett A. Stroozas, Data Analysis Support Staff (DASS)
and Archive Manager
Welcome to the electronic newsletter for NASA's Extreme Ultraviolet Explorer
(EUVE) satellite, which is compiled and published monthly by the EUVE Science
Archive group at the Center for EUV Astrophysics (CEA) in Berkeley, CA. The
EUVE observatory performed well throughout the month of July, completing
observations of the following Guest Observer (GO) targets: the planet Jupiter
for the comet Shoemaker-Levy 9 impact (see section 1.2 below), the early-type
star alpha Eri (spectral type B3vpe), the white dwarfs GD246 (DAw) and
RE2009-602 (DA), and the star cluster M15. (All spectral types indicated
above were taken from the SIMBAD database.) A short survey-mode observation
to calibrate the on-board gyroscopes was also conducted.
The contents of this issue of the EUVE electronic newsletter are as follows:
1. Notes from the EUVE Guest Observer (EGO) Center
1.1 Third EUVE NRA
1.2 Early Results of the SL-9/Jupiter Impact Observations
1.3 New Home Page on WWW
2. Notes from the EUVE Science Archive
2.1 GO Data Release List for September 1994
2.2 New Documentation and Services
2.3 Accessing the Archive
3. Abstracts of Recently *Accepted* EUVE Papers
To comment on, make suggestions for, or request subscriptions to the EUVE
electronic newsletter, send e-mail to ceanews@cea.berkeley.edu (Internet).
1. Notes from the EUVE Guest Observer (EGO) Center
==================================================
by Anne Miller, EGO Technical Writer
1.1 Third EUVE NRA
------------------
The 3rd EUVE Guest Observer Program NASA Research Announcement (NRA) will
be released on 16 August. The mailing will consist of a brief description of
the program and a call for proposals. All other materials, including the
complete NRA text and appendices, the forms for paper and electronic submission,
and the instrument calibration data will be made available on the same date on
the World-Wide-Web (WWW) using the Uniform Resource Locator (URL):
ftp://cea-ftp.cea.berkeley.edu/pub/nra94
This path is equivalent to using standard ftp to open the anonymous site:
cea-ftp.cea.berkeley.edu
and typing "cd /pub/nra94". A detailed overview of the electronic materials
for the NRA will be distributed in a future edition of this newsletter.
1.2 Early Results of the SL-9/Jupiter Impact Observations
---------------------------------------------------------
EUVE observed the impact of comet Shoemaker-Levy 9 on Jupiter which occurred
from 16-30 July. Dr. Randy Gladstone of the Southwest Research Institute, a
co-investigator GO with Doyle Hall of the Johns Hopkins University, reports the
following:
"The Jupiter spectrum obtained so far shows strong helium
emissions during the impacts that were not present immediately
before the impacts began. The strongest emission is at 584 A.
An additional feature at 504 A indicates that the emissions may
result from recombination of helium ions. The presence of these
emissions imply that substantial amounts of helium and/or helium
ions have been lifted to high altitudes in Jupiter's upper
atmosphere. Other features are present in the spectrum but are
currently unidentified."
1.3 New EGO Center Home Page on WWW
-----------------------------------
The EGO Center's WWW Home Page has a new format, with summary text on each
of the selections. New users may first select "how to use this site" for an
introduction. In addition to the existing "target visibility" and interstellar
medium (ISM) transmission "ISM" tool, there is a link to the new CEA "ISM
Hydrogen Column" tool. Given a set of coordinates and a distance, this tool
reports the measured hydrogen column densities for the ten objects nearest the
target location, using a list from "The Distribution of Neutral Hydrogen in the
Interstellar Medium (Fruscione et al., 1994)". Publicly available information
on EUVE GO program proposals for Cycles I and II has also been added, as well
as a link to the EUVE Science Archive which has facilities for ordering publicly
released spectral data sets. Please send your comments and feedback on the new
Home Page using the mail address at the bottom of that page.
2. Notes from the EUVE Science Archive
======================================
by Brett A. Stroozas, DASS/Archive Manager
2.1 GO Data Release List for September 1994
------------------------------------------------------
The table below lists the GO observations which become public on 1 September
1994. For each entry is given the target name, the approximate exposure time
in kiloseconds, the GMT start and end date(s) for the observation, the spectral
type of the target, an indication of which (if any) EUVE CD-ROM on which the
observation appears, and the data identification code. All public data sets
may be ordered from the archive via CEA electronic (e.g., "mailorder go0001")
or postal mail. Please be sure to include in your order the DataID(s) of
interest.
The data rights policy on GO observations states that the GO has proprietary
rights to the data for one year from the date (s)he receives it. It is often
the case that long observations are broken up over many months; e.g. an
observation approved for 60 ksec may actually be observed for 10 ksec one
month, 20 ksec the next and 30 ksec three months later. In such cases the
one-year proprietary period begins after the GO receives the final piece of
the complete observation. An exception to the one-year rule occurs when the
target was designated for calibration purposes. At the discretion of the
EUVE Project Scientist, calibration observations may be released before the
expiration of the normal one-year period (usually by only a few months). In
the list below, calibration targets have been marked with a "*".
=====================================================================
Target ~Exp Observation Date(s) SpT CD-ROM DataID
Name (ksec) Start End
=====================================================================
Data Sets Available 1 Sep 1994:
HD149499_B 99 23 Jun 1993 - 27 Jun 1993 K0V ---- go0086
HD165341 86 2 Jul 1993 - 5 Jul 1993 K0V ---- go0087
HD223816 67 6 Aug 1993 - 8 Aug 1993 F5IV ---- go0091
HR8210 98 23 Jul 1993 - 27 Jul 1993 A8m ---- go0090
HS1234+4811 86 19 Feb 1993 - 22 Feb 1993 WD ---- go0053
MCT2331-4731 57 8 Aug 1993 - 10 Aug 1993 WD ---- go0089
MOON 2 30 Jun 1993 - 30 Jun 1993 SS ---- go0088
SS_CYG 187 17 Aug 1993 - 23 Aug 1993 A1pe ---- go0092
=====================================================================
2.2 New Documentation and Services
----------------------------------
The Archive is pleased to announce some newly released EUVE material.
The following are now available via the WWW from the CEA URL
(http://cea-ftp.cea.berkeley.edu):
* A new "Frequently Asked Questions" (FAQ) list is now available (see "FAQ"
listing under "About the EUVE Archive").
* A new service -- the ISM hydrogen column density search tool -- is now
available (see the "ISM Hydrogen Column Density Search Tool" listing
under "Software & Services"). Based on the database compiled by
Fruscione, et al. (1994), this service allows researchers to obtain
hydrogen column density information for the ten stars nearest a given
position (equatorial or galactic coordinates) within a given distance
(parsecs).
* The CEA EUVE bibliography is now available (see the "EUVE Bibliography"
listing under "Documentation"). The bibliography has been sorted and
categorized to assist researchers in locating papers of interest.
Hypertext links to over 60 on-line papers are now available; additional
links will continued to be added as more papers are put on-line.
* The first two issues of the EUVE Science Bulletin -- from January and June
1994 -- are now available (see the "Science Bulletin" listing under
"Documentation"). The Science Bulletin, issued twice each year, is a
collection of articles, abstracts and general information which focuses
on the science results from the EUVE mission.
* The spectral data browser (see the "Spectra" listing under "Data") has been
updated with the spectra for the GO data sets released 1 August.
In addition, a supplemental table to The First EUVE Source Catalog (FESC;
Bowyer, et al., 1994) is now available from the CEA node of NASA's Astrophysics
Data System (ADS). This catalog is called "euve_cat1supp" and is listed under
the "Data:Catalogs" menu in ADS. It corresponds to Table 7 from the FESC paper
and contains those sources from the Bright Source List (Malina, et al., 1994)
which did not meet the more stringent detection criteria set forth in the FESC.
2.3 Accessing the Archive
-------------------------
Listed below are the various methods for accessing EUVE archival material:
o CEA World Wide Web URL:
http://cea-ftp.cea.berkeley.edu (Mosaic/lynx remotely)
telnet cea-ftp.cea.berkeley.edu 200 (lynx locally at CEA)
o NASA's Astrophysics Data System (general and account information):
http://adswww.colorado.edu/adswww/adshomepg.html (Mosaic/lynx)
ads@cuads.colorado.edu
o CD-ROM Series: Volumes 1.1, 2.1, and 2.2 (seven separate CDs) available
o e-mail: archive@cea.berkeley.edu
(include word "help" -- quotes omitted -- as body of message)
o anonymous FTP (or gopher): cea-ftp.cea.berkeley.edu
o EUVE Electronic Newsletters: ceanews@cea.berkeley.edu (to subscribe)
o Postal Mail:
The EUVE Public Science Archive
Center for EUV Astrophysics
2150 Kittredge St.
Berkeley, CA 94720
510-642-3032 (voice) or 510-643-5660 (fax)
archive@cea.berkeley.edu
3. Abstracts of Recently *Accepted* EUVE Papers
===============================================
Included below are abstracts of EUVE-related papers recently *accepted*
for publication. GOs are encouraged to contribute *accepted* abstracts for
inclusion in future editions of this newsletter and for posting under the
EGO Center Mosaic "Home Page". All abstracts should be sent to
egoinfo@cea.berkeley.edu.
For those papers authored by CEA scientists, the EUVE publication number is
indicated. Unless otherwise noted, researchers may obtain preprints of these
papers by sending an e-mail request along with the publication number(s) of
interest to pub@cea.berkeley.edu.
--------------------------------------------------------------
A CATALOG OF FAR-ULTRAVIOLET POINT SOURCES DETECTED WITH THE FAUST TELESCOPE
ON ATLAS-1
S. Bowyer, T.P. Sasseen, X. Wu, and M. Lampton
To appear in Astrophysical Journal Supplement
[CEA publication #594]
We list the photometric measurements of point sources made by the Far
Ultraviolet Space Telescope (FAUST) when it flew on the ATLAS-1 space shuttle
mission. The list contains 4,698 Galactic and extragalactic objects detected
in 22 wide-field images of the sky. At the locations surveyed, this catalog
reaches a limiting magnitude approximately a factor of 10 fainter than the
previous UV all-sky survey, TD1. The catalog limit is approximately 1e-14
ergs s^(-1) cm^2 A, although it is not complete to this level. We list for
each object the position, FUV flux, the error in flux, and where possible an
identification from catalogs of nearby stars and galaxies. These catalogs
include the Michigan HD (MHD) and HD, SAO, the Hipparcos Input catalog, the
Position and Proper Motion Catalog, the TD1 Catalog, the McCook & Sion Catalog
of white dwarf stars, and the RC3 Catalog of Galaxies. We identify 2239 FAUST
sources with objects in the stellar catalogs and 172 with galaxies in the RC3
catalog. We estimate the number of sources with incorrect identifications to
be less than 2%.
--------------------------------------------------------------
THE PRE-CATACLYSMIC BINARY EUVE 2013+400
J.R. Thorstensen, S. Vennes, and A. Shambrook
To appear in Astronomical Journal
[CEA publication #596]
New optical spectroscopy shows a 0.706 d orbital period for EUVE 2013+400
and confirms its membership in a class of close binary systems emerging from
common-envelope evolution. This binary, like the prototype Feige 24, consists
of an extreme ultraviolet (EUV)-emitting hot white dwarf and a late-type dwarf.
Bergeron et al's (1994) optical spectroscopy and ultraviolet spectrophotometry
indicate that the white dwarf is hot (T_eff ~= 50,000 K) and therefore very
young (T_age <= 5e6 yrs), and extreme ultraviolet photometry places EUVE
2013+400 along a neutral hydrogen column density in the interstellar medium
of n_H ~= 1e19 cm^(-2). The white dwarf is a DAO-type and we obtained two
independent estimates of the helium abundance from EUV photometric measurements
(log(y) ~= -3.2) and from the HeII 4686 A line profile (log(y) ~= -2.8).
The data possibly indicate a level of heterogeneity expected in the context
of on-going chemical separation in the photospheric layers. The Balmer lines
show narrow emission that varies with binary phase with the equivalent widths
of the emission trailing the radial velocities by 1/4 cycle: this phasing
shows that most of the emission arises on the EUV-illuminated face of the red
dwarf. A spectrophotometric decomposition shows that the secondary's spectral
type is near M3 and that it contributes about 15-25% of the total light near
6500 A; the resulting H-alpha emission is twice as strong as in Feige 24,
with an equivalent width of 37-61 A with respect to the red dwarf continuum.
EUVE 2013+400 is an important addition to the class of close binary stars
discovered in EUV all-sky surveys.
--------------------------------------------------------------
THE LOCAL DISTRIBUTION OF NaI INTERSTELLAR GAS
B.Y. Welsh, N. Craig, P.W. Vedder, and J.V. Vallerga
To appear in Astrophysical Journal
[CEA publication #597]
We present high-resolution absorption measurements (lambda/d-lambda ~75,000)
of the interstellar NaI D-lines at 5890 A toward 80 southern hemisphere
early-type stars located in the local interstellar medium (LISM). Combining
these results with other sodium measurements taken from the literature, we
produce galactic maps of the distribution of neutral sodium column density for
a total of 293 stars generally lying within ~250 pc of the Sun. These maps
reveal the approximate shape of the mid-plane contours of the rarefied region
of interstellar space termed the Local Bubble. Its shape is seen as highly
asymmetric, with a radius ranging from 30-300 pc, and with an average radius
of 60 pc. Similar plots of the galactic mid-plane distribution of sources
emitting extreme ultraviolet radiation show that they also trace out similar
contours of the Local Bubble derived from NaI absorption measurements. We
conclude that the Local Bubble absorption interface can be represented by a
hydrogen column density, N_H = 2e19 cm^(-2), which explains both the local
distribution of NaI absorption and the observed galactic distribution of
extreme ultraviolet sources. The derived mid-plane contours of the Bubble
generally reproduce the large-scale features carved out in the interstellar
medium by several nearby galactic shell structures.
--------------------------------------------------------------
REFERENCES
==========
Bowyer, S., et al., The First EUVE Source Catalog, Astrophysical Journal
Supplement, 93(2), 1994 [CEA publication #565]
Fruscione, A., et al., The Distribution of Neutral Hydrogen in the Interstellar
Medium. I. The Data, Astrophysical Journal Supplement, September 1994
(in press) [CEA publication #575]
Malina, R.F., et al., The Extreme Ultraviolet Explorer Bright Source List,
Astronomical Journal, 107(2), 751-764, 1994 [CEA publication #553]
---------------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme Ultraviolet
Astrophysics, University of California, Berkeley, CA 94720, USA. The opinions
expressed are those of the authors. EUVE Principal Investigators and Newsletter
Publishers: Drs. R.F. Malina and C.S. Bowyer. EGO and Archive Science Manger:
C.A. Christian. Archive Manager and Newsletter Editor: B.A. Stroozas. Funded
by NASA contracts NAS5-30180 and NAS5-29298. Send newsletter correspondence
to: ceanews@cea.berkeley.edu. The EUVE project is managed by NASA's GSFC.
The GSFC Project Manager: Paul Pashby, Project Scientist: Dr. Yoji Kondo,
Deputy Project Scientist: Dr. Ronald Oliversen. NASA HQ Program Scientist:
Dr. Robert Stachnik, Program Manager: Dr. G. Riegler. GSFC Project Operations
Director: Mr. Kevin Hartnett. Information on the EUVE Guest Observer Program
is available from: Dr. Y. Kondo, Mail Code 684, GSFC, Greenbelt, MD 20771 at
(301) 286-6247 or e-mail to euve@stars.span.nasa.gov.
END-----------EUVE------------ELECTRONIC---------------NEWS-------------END
% ====== Internet headers and postmarks (see DECWRL::GATEWAY.DOC) ======
% Date: Wed, 10 Aug 1994 17:52:51 -0700
% From: EUVE Electronic Newsletter distribution <ceanews@cea.Berkeley.EDU>
% Message-Id: <199408110052.RAA03874@imperial.cea.berkeley.edu>
% To: euvenews@cea.Berkeley.EDU
% Subject: EUVE Electronic Newsletter
|
| 770.41 | | skylab.zko.dec.com::FISHER | 25 Years Ago: Tranquility base here. The Eagle has landed. | Fri Aug 12 1994 16:42 | 4 |
| BTW, there is a pretty interesting article on EUVE and EUV astronomy in general
in the latest issue (August? Sept? 94) issue of Scientific American.
Burns
|
| 770.42 | More time for reading now.... | 4371::BATTERSBY | | Fri Aug 12 1994 17:07 | 4 |
| ...Saw that, but haven't had a chance to read the article yet.
I will have more time now that the baseball strike is upon us.
Bob
|
| 770.43 | AI to run EUVE more often | 30254::KLAES | No Guts, No Galaxy | Fri Aug 19 1994 18:49 | 123 |
| From: US1RMC::"ceanews@imperial.cea.berkeley.edu" "EUVE Electronic
Newsletter distribution" 18-AUG-1994 22:06:59.61
To: usenet-space-news@arc.nasa.gov
CC:
Subj: EUVE Automation Press Release
EMBARGOED FOR IMMEDIATE RELEASE:
(Jointly issued by UCB and Talarian Inc.)
Contacts: Ms. Jennifer Hinchman, Center for EUV Astrophysics
(510) 643-5669 / jenhinch@cea.berkeley.edu
Mr. Tom Morgan, Center for EUV Astrophysics
(510) 643-7277 / tomm@cea.berkeley.edu
Ms. Calisa Cole, Cole Communications (Talarian Corp.)
(415) 324-3152 / calisa@aol.com
UCB adopts artificial intelligence approach to demonstrate low-cost
satellite observatory operations strategy for NASA and Aerospace Industry;
Talarian's RTworks Provides High-Speed Inferencing Capabilities
--------------------------------------------------------------------------
On November 1st, 1994, researchers at UC Berkeley's Center for Extreme
Ultraviolet Astrophysics (CEA) will lock the doors of the NASA's
Extreme Ultraviolet Explorer (EUVE) Science Operations Center (ESOC),
leaving only the computer network to monitor the satellite payload for
a 14-hour unstaffed shift.
The enabling technology for this transition is a suite of artificial
intelligence (AI) software called E-tools that will allow the ESOC to
be unstaffed for extended periods of time while AI-based software
conducts health and safety tests on the EUVE science instrument aboard
the satellite. Pending NASA approval, EUVE will be the first orbiting
astrophysics mission to replace humans with AI technology.
"We are developing a low-cost automated approach now, to be prepared
for the budget cuts of tomorrow" says Dr. Roger Malina, EUVE Principal
Investigator for mission operation and data analysis. CEA has redesigned
the operations of the 2 year old ESOC to create a more efficient, low-cost,
model that maintains the current science return of 99.5%.
E-tools is a synthesis of commercial off-the-shelf (COTS), NASA
developed, and UCB developed software. Researchers at UCB, the Jet
Propulsions Laboratories (JPL) and NASA Ames Research Center (ARC),
used RTworks(R) software from Talarian Corporation and SUN Net Manager
from Sun Soft, a SUN Microsystems Inc. business in developing an
integrated set of software applications that mimic the monitoring
responsibilities of human science payload controllers.
"We selected a COTS monitoring package based on its extensibility and
modularity and have successfully integrated it into our existing
operational systems. We have designed the system to be highly
maintainable, with a heavy re-use of code" says software engineer
Forrest R. Girouard, referring to the general philosophy behind the
architecture of E-tools. The system is designed to be expandable as
well as low-cost to implement.
The AI software perpetually monitors the science payload using an
inference engine built with RTworks(R). The inference engine contains
over 500 "rules." When a rule is violated by a data point in the
telemetry stream, calls are made to external processes that either
rectify the problem or sound an alarm. If a problem occurs during an
unstaffed shift the software autonomously pages, via beeper, an
anomaly response coordinator.
"We're really breaking new ground here, not only technically, but also
programatically... the most difficult challenges to address are those
rooted in cultural resistance to change," says Malina. Traditionally,
NASA missions are not designed to operate in an autonomous fashion.
Dr. Mel Montemerlo of the NASA Office of Advanced Concepts and
Technology (OACT) and Dr. Guenter Riegler from the Office of Space
Sciences- Astrophysics Division (OSSA) converged in a strategic
alliance to assist the EUVE project by directing leading NASA experts
from ARC and JPL. Dr. Peter Friedland and Dr. David Korsmeyer of ARC
transferred their skill in knowledge engineering to UCB through
counseling, new methodologies, and actual programming of a subset of
the E-tools knowledge base.
The modular architecture design has allowed UCB the flexibility of
working with NASA and industry software developers in a testbedding
function. Active collaborations exist to implement and assess
prototype software, picking and choosing only value-added additions or
augmentations that prove valuable to future or current NASA missions.
CEA maintains a program to evaluate technology in an operational
real-life, in-orbit situation and provides the evaluations to the
software developers' target market via World Wide Web and Mosaic
(http://cea-ftp.cea.berkeley.edu). "We're very customer driven, the
researcher gives us an idea of his intended market, we attempt to
provide the most relevant evaluation information for that sector,"
comments innovative technology testbed manager Tom Morgan.
In a climate of scepticism, successful operations histories are as
important as the technology itself to persuade mission managers to
adopt new and innovative approaches. "We have a lot of talent working
with us, and we are dedicated as a research department and a
collaborative partner to facilitate low-cost, high-technology mission
operations for NASA missions, and to that end our largest asset
remains our vision," comments Malina.
-----------------------------
The UC Berkeley Center for Extreme Ultraviolet Astrophysics,
University of California, Berkeley, CA 94720-5030, USA. Principal
Investigator for Mission Operations and Data Analysis for the EUVE
Mission is: Dr. Roger Malina, Work is funded by NASA contract
NAS5-29298. The EUVE project is managed by NASA's Goddard Space
Flight Center. The GSFC Project Manager: Paul Pashby, Project
Scientist: Dr. Yoji Kondo, Deputy Project Scientist: Dr. Ronald
Oliversen. NASA HQ Senior Program Scientist: Dr. Robert Stachnik, Dep.
Program Scientist: Dr. Darrell New, Chief Scientist: Dr. G. Riegler.
GSFC Project Operations Director: Mr. Kevin Hartnett: EUVE Project
Technologist, Mr. Peter Hughes. Collaborators on Science Operations
Enhancements are: Dr. Mel Montemerlo, NASA Code C, Dr. David Atkinson,
Jet Propulsion Laboratory, Dr. Peter Fiedland, NASA Ames Research Center
Talarian Corporation's RTworks is a family of software products for
building high-performance client/server applications that
intelligently manage time-critical data. The company is located in
Mountain View, California.
|
| 770.44 | August 29 | MTWAIN::KLAES | No Guts, No Galaxy | Wed Aug 31 1994 16:37 | 170 |
| From: VERGA::US4RMC::"ceanews@cea.Berkeley.EDU" "EUVE Electronic Newsletter
distribution" 29-AUG-1994 22:16:09.57
To: euvenews@cea.Berkeley.EDU
CC:
Subj: Public Release of EUVE Sky Survey Data
EEEEEEEEEEE U U V V EEEEEEEEEEE
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ELECTRONIC "FLASH" OF THE EUVE OBSERVATORY
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Vol 4, No. 8b 29 Aug 1994 ISSN 1065-3597
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**************************************************
* *
* *
* PUBLIC RELEASE OF THE EUVE SKY SURVEY DATA *
* *
* *
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by Brett A. Stroozas
EUVE Science Archive Manager
The Center for Extreme Ultraviolet Astrophysics (CEA) is pleased to
announce the public release of the sky survey data from NASA's Extreme
Ultraviolet Explorer (EUVE) satellite. EUVE was launched on 7 June 1992,
from Cape Canaveral, Florida, into a near-Earth (550 km) orbit. Following
seven weeks of in-orbit checkout, the survey phase of the mission was carried
out from 24 July 1992 until 21 January 1993 and included the following:
* an all-sky survey conducted by the three "scanning" telescopes in four
band passes covering the entire extreme ultraviolet wavelength range
(60-740 A);
* a concurrent "deep survey" (more sensitive by a factor of ten) of a
2x180 degree swath along the ecliptic conducted by the deep survey
telescope in two band passes covering the 70-365 A range.
Periods of gap-fill (e.g., due to pointed calibration observations made
during the survey) were carried out during the first six months of the Guest
Observer (GO) program. The completed survey data sets cover approximately
97% of the sky with exposures ranging from a few hundred seconds at the
ecliptic equator to 20 kiloseconds at the poles.
Survey Science Data Products
----------------------------
The main science data products from the survey include source catalogs,
skymaps and "pigeonholes". Two catalogs of the survey results have been
published in the literature: "The Extreme Ultraviolet Explorer Bright Source
List" (Malina, et al. 1994); and "The First EUVE Source Catalog" (Bowyer,
et al. 1994). For the confirmed detected sources contained therein, these
catalogs furnish coordinates, approximate count-rates (to within ~50%), and
optical identifications (where available).
The survey sky maps are packaged as sets of binned raw photon (~1.3'
resolution) and exposure (~10' resolution) FITS maps for each survey band
pass.
An EUVE "pigeonhole" is a file which contains the time-tagged photon event
information within a small radius (typically 0.4 degrees) of a given location
on the sky. The pigeonhole files, which provide the maximum amount of available
information for each target location, are available in FITS bintable format.
Survey Data Accessible Via WWW URL
----------------------------------
Access to the EUVE science data products is now available via the CEA
World-Wide-Web (WWW) URL:
http://www.cea.berkeley.edu
(formerly http://cea-ftp.cea.berkeley.edu). For those not having the relevant
software (e.g., NCSA's Mosaic), a text-based version is available locally at
CEA via telnet:
telnet www.cea.berkeley.edu 200
Three services -- the EUVE Count-Rate, the Skymap Request and the Pigeonhole
Request service -- have been implemented to provide researchers with access
to the EUVE survey data products. Due to the size and complexity of the data
products provided, as well as to the processing and delivery time involved, we
recommend that researchers access these products in the following manner:
1. SEARCH CATALOGS -- Researchers are first encouraged to search the published
catalogs for source(s) of interest. The full text and tables of the
survey catalogs (Malina, et al. 1994; Bowyer, et al. 1994), which
cover both the all-sky and deep surveys, are available on-line. A
tool to assist users in searching these catalogs will soon be available.
2. OBTAIN SOURCE COUNT-RATE INFORMATION -- Researchers may obtain source
count-rate information (e.g., for those sources not appearing in the
published catalogs) by using the EUVE Count-Rate service. This service
calculates count-rate information for *point* sources only by searching
and analyzing the skymaps for any significant source(s) near an input
location. Count-rate results are processed within hours and returned
via e-mail to the requester. This service currently provides access
to the all-sky survey skymaps only; those from the deep survey skymaps
will be available in the future.
3. OBTAIN SOURCE SKYMAP -- For those sources for which the EUVE Count-Rate
service indicates significant detections, the researcher is encouraged
to verify these results by obtaining and examining images of the source
by using the EUVE Skymap Request service. For a given input location
this service creates small raw photon (1.3' resolution) and exposure
(10' resolution) skymaps in FITS image format. When completed, the
requester is notified via e-mail that the skymaps are available for
pick-up in the CEA anonymous ftp site (www.cea.berkeley.edu). This
service currently provides access to the all-sky survey skymaps only;
the deep survey skymaps will be available in the future.
4. OBTAIN SOURCE PIGEONHOLE -- For detailed count-rate and timing analyses the
researcher will need the pigeonhole information which is accessible via
the EUVE Pigeonhole Request service. Given an input location, this
service will create a pigeonhole from the survey data in FITS Bintable
format. When completed (which may take up to five days), the requester
will be notified via e-mail that the pigeonhole is available for pick-up
in the CEA anonymous ftp site. Researchers should note that, although
pigeonholes contain the maximum amount of scientific information for a
given source, they are also the most complicated data products to
understand and use. Proper interpretation of pigeonhole data requires
the use of supplemental calibration data -- effective areas, point-
spread-functions and vignetting maps -- which are also available.
Detailed documentation is provided on-line for all of the above. Over the
coming months the EUVE Science Archive will continue to work on improving and
augmenting the available survey data, services and accompanying documentation.
Please help us to help you with your EUVE research by sending your questions,
comments and/or suggestions to archive@cea.berkeley.edu.
REFERENCES
==========
o Bowyer, S., Lieu, R., Lampton, M., Lewis, J., Wu, X., Drake, J.J., and
Malina, R.F., "The First EUVE Source Catalog", Astrophysical Journal
Supplement, 93(2), 1994 [CEA publication #565]
o Malina, R.F., et al., "The Extreme Ultraviolet Explorer Bright Source List"",
Astronomical Journal, 107(2), 751-764, 1994 [CEA publication #553]
---------------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme Ultraviolet
Astrophysics, University of California, Berkeley, CA 94720, USA. The opinions
expressed are those of the authors. EUVE Principal Investigators and Newsletter
Publishers: Drs. R.F. Malina and C.S. Bowyer. EGO and Archive Science Manger:
C.A. Christian. Archive Manager and Newsletter Editor: B.A. Stroozas. Funded
by NASA contracts NAS5-30180 and NAS5-29298. Send newsletter correspondence
to: ceanews@cea.berkeley.edu. The EUVE project is managed by NASA's GSFC.
The GSFC Project Manager: Paul Pashby, Project Scientist: Dr. Yoji Kondo,
Deputy Project Scientist: Dr. Ronald Oliversen. NASA HQ Program Scientist:
Dr. Robert Stachnik, Program Manager: Dr. G. Riegler. GSFC Project Operations
Director: Mr. Kevin Hartnett. Information on the EUVE Guest Observer Program
is available from: Dr. Y. Kondo, Mail Code 684, GSFC, Greenbelt, MD 20771 at
(301) 286-6247 or e-mail to euve@stars.span.nasa.gov.
END-----------EUVE------------ELECTRONIC---------------NEWS-------------END
% ====== Internet headers and postmarks (see DECWRL::GATEWAY.DOC) ======
% Date: Mon, 29 Aug 1994 16:56:42 -0700
% From: EUVE Electronic Newsletter distribution <ceanews@cea.Berkeley.EDU>
% Message-Id: <199408292356.QAA07183@imperial.cea.berkeley.edu>
% To: euvenews@cea.Berkeley.EDU
% Subject: Public Release of EUVE Sky Survey Data
|
| 770.45 | September 14 | MTWAIN::KLAES | No Guts, No Galaxy | Thu Sep 15 1994 16:40 | 395 |
| From: VERGA::US4RMC::"ceanews@cea.Berkeley.EDU" 14-SEP-1994 23:36:25.71
To: euvenews@cea.Berkeley.EDU
CC:
Subj: EUVE Electronic Newsletter
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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
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Vol 4, No. 9 14 Sep 1994 ISSN 1065-3597
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Notes from the Editor
=====================
by Brett A. Stroozas, EUVE Data Analysis Support Staff (DASS)
and Science Archive Manager
Welcome to the electronic newsletter for NASA's Extreme Ultraviolet Explorer
(EUVE) satellite, which is compiled and published monthly by the EUVE Science
Archive group at the Center for EUV Astrophysics (CEA) in Berkeley, CA. The
EUVE observatory performed well throughout the month of August, completing
observations of the following Guest Observer (GO) targets (spectral types,
taken from the SIMBAD database, are indicated in parentheses): Wolf 630
(M3Ve), GD 246 (WD), Jupiter, EUVE J2214-49.3 (WD), RE 1844-741 (CV), the Moon,
and a calibration observation of HR 1099 (G5IV+K1IV). An engineering test to
calibrate the electronic "wedge-strip-zigzag" detectors was also conducted.
The contents of this issue of the EUVE electronic newsletter are as follows:
1. Notes from the EUVE Science Archive
1.1 Public Release of the EUVE Sky-Survey Data
1.2 GO Data Release List for October 1994
1.3 CEA Network Server Change
1.4 majordomo Server for Newsletter
1.5 Accessing the Archive
2. Abstracts of Recently *Accepted* EUVE Papers
3. CEA Job Listings
1. Notes from the EUVE Science Archive
======================================
by Brett A. Stroozas, DASS/Archive Manager
1.1 Public Release of the EUVE Sky-Survey Data
----------------------------------------------
As announced in the recent news "flash" of 29 August, CEA is pleased to
announce the public release of the EUVE sky-survey data. The completed survey
data sets cover approximately 97% of the sky in four band passes (60-740 A)
with exposures ranging from a few hundred seconds at the ecliptic equator to
20 kiloseconds at the poles.
The main science data products from the survey include the following:
o source catalogs -- Two catalogs of the survey results have been published in
the literature: "The Extreme Ultraviolet Explorer Bright Source List"
(Malina, et al. 1994); and "The First EUVE Source Catalog" (Bowyer, et
al. 1994). For the confirmed detected sources contained therein, these
catalogs furnish coordinates, approximate count-rates (to within ~50%),
and optical identifications (where available).
o skymaps -- The survey skymaps are packaged as sets of binned raw photon
(~1.3' resolution) and exposure (~10' resolution) FITS maps for each
survey band pass.
o pigeonholes -- An EUVE "pigeonhole" is a file which contains the time-tagged
photon event information within a small radius (typically 0.4 degrees)
of a given location on the sky. The pigeonhole files provide the
maximum amount of information for each target location and are
available in FITS bintable format.
The above science data products are available from the CEA World Wide Web
(WWW) URL:
http://www.cea.berkeley.edu
Three services -- the EUVE Count-Rate, the Skymap Request and the Pigeonhole
Request service -- provide access to the various data products. These data
products vary in their complexity and require different levels of processing,
delivery and analysis time. Because of this, and in order to minimize the
efforts required by the researcher, the Archive recommends that users access
the data in the following manner:
1. Search the available catalogs for sources of interest.
2. Use the EUVE Count-Rate service to obtain count-rate information on these
sources.
3. Use the Skymap Request service to obtain skymaps for interesting sources.
4. Use the Pigeonhole Request service to obtain source pigeonholes.
Detailed documentation on all of the above is available on-line. The Archive
will continue to improve and augment the available survey data, services and
accompanying documentation. Please help us to help you with your EUVE research
by sending your comments and/or suggestions to archive@cea.berkeley.edu.
1.2 GO Data Release List for October 1994
-----------------------------------------
The table below lists the GO observations which become public on 1 October
1994 (all have been reprocessed with the most recent versions of the EGO Center
software and reference data). For each entry is given the target name, the
approximate exposure time in kiloseconds, the GMT start and end date(s) for
the observation, the spectral type of the target, and the data identification
code. All public data sets may be ordered from the archive via World Wide Web
URL and electronic or postal mail (see addresses below). Please be sure to
include in your order the DataID(s) of interest.
The data rights policy for GO observations states that GO's have proprietary
rights to the data for one year from the date (s)he receives it. It is often
the case that long observations are broken up over many months; e.g. an
observation approved for 60 ksec may actually be observed for 10 ksec one
month, 20 ksec the next and 30 ksec three months later. In such cases the
one-year proprietary period begins after the GO receives the final piece of
the complete observation.
===============================================================
Target ~Exp Observation Date(s) SpT DataID
Name (ksec) Start End
===============================================================
Data Sets Available 1 Oct 1994:
CYG_1992 40 08/23/93 - 08/25/93 Nva go0093
EF_ERI 118 09/05/93 - 09/08/93 CV go0094
EQ_PEG 37 08/29/93 - 08/30/93 M4Ve go0095
EV_LAC 118 09/09/93 - 09/13/93 M4V go0096
GRB250392 39 08/25/93 - 08/26/93 GRB go0097
HD15638 84 09/02/93 - 09/05/93 F+WD go0098
HER_X-1 113 08/10/93 - 08/14/93 Puls go0099
MK478 70 04/09/93 - 04/11/93 AGN go0100
MK478 70 04/11/93 - 04/14/93 AGN go0057
MK478 66 04/14/93 - 04/16/93 AGN go0056
MK478 65 04/16/93 - 04/18/93 AGN go0055
RE2156-543 48 08/14/93 - 08/16/93 WD go0101
RE2214-491 78 08/26/93 - 08/29/93 WD go0102
RE2237-135 30 09/21/93 - 09/22/93 NOID go0103
RE2303+212 29 09/22/93 - 09/23/93 NOID go0104
WD2111+498 73 09/13/93 - 09/16/93 WD go0105
===============================================================
1.3 CEA Network Server Change
-----------------------------
In order to conform to a growing "standard" naming convention, as well as
to be more intuitive for users, the name of the CEA network server has been
changed to
www@cea.berkeley.edu
We encourage all users to access CEA at this address. The old address --
cea-ftp.cea.berkeley.edu -- will continue to work for a time.
1.4 majordomo Server for Newsletter
-----------------------------------
The mail list for subscriptions to this newsletter has recently been added
to the CEA "majordomo" server. In addition to simplifying maintenance of mail
lists, majordomo provides flexible mail server utilities which allow users to
subscribe to and unsubscribe from lists, retrieve previous messages, and send
messages to the list subscribers.
The newsletter mail list -- euvenews -- is the most recent addition to the
available CEA lists. To retrieve information regarding the euvenews list and
its available associated material (e.g., past newsletter issues), send mail to
majordomo@cea.berkeley.edu
including one or more of the following commands in the body of the message:
* help --> request generic help on majordomo commands
* index euvenews --> request index of available files from euvenews list
* get euvenews <file> --> request the file <file> from euvenews list
All commands should be sent on a separate line in the mail message; a message
may contain multiple commands.
To post a message to all newsletter subscribers (not including yourself),
send mail to euvenews@cea.berkeley.edu. Please be *very* careful when using
this address; make sure that only relevant material is posted to the newsletter
subscribers. If you have comments and/or suggestions regarding the newsletter
and majordomo list/server, please send them to archive@cea.berkeley.edu.
1.5 Accessing the Archive
-------------------------
Listed below are the various methods for accessing EUVE archival material:
o CEA World Wide Web URL:
http://www.cea.berkeley.edu (Mosaic/lynx remotely)
telnet www.cea.berkeley.edu 200 (lynx locally at CEA)
o NASA's Astrophysics Data System (general and account information):
http://adswww.colorado.edu/adswww/adshomepg.html (Mosaic/lynx)
ads@cuads.colorado.edu
o CD-ROM Series: Volumes 1.1, 2.1, and 2.2 (seven separate CDs) available
o e-mail: archive@cea.berkeley.edu
(include word "help" -- quotes omitted -- as body of message)
o anonymous FTP (or gopher): www.cea.berkeley.edu
o EUVE Electronic Newsletters:
Subscriptions: majordomo@cea.berkeley.edu ("subscribe euvenews")
Post message to subscribers: euvenews@cea.berkeley.edu
o Postal Mail:
The EUVE Public Science Archive
Center for EUV Astrophysics
2150 Kittredge St.
Berkeley, CA 94720
510-642-3032 (voice) or 510-643-5660 (fax)
archive@cea.berkeley.edu
2. Abstracts of Recently *Accepted* EUVE Papers
===============================================
Included below are abstracts of EUVE-related papers recently *accepted*
for publication. GOs are encouraged to contribute *accepted* abstracts for
inclusion in future editions of this newsletter and for posting under the
EGO Center Mosaic "Home Page". All abstracts should be sent to
egoinfo@cea.berkeley.edu.
For those papers authored by CEA scientists, the EUVE publication number
is indicated. Unless otherwise noted, researchers may obtain preprints of the
CEA papers by sending an e-mail request along with the publication number(s)
of interest to pub@cea.berkeley.edu.
--------------------------------------------------------------
OBSERVATIONS OF HER X-1/HZ HER
S.D. Vrtilek, T. Mihara, F.A. Primini, P. Kahabka, H. Marshall, F. Agerer,
P.A. Charles, F.H. Cheng, K. Dennerl, C. la Dous, E.M. Hu, R. Rutten,
P. Serlemitsos, Y. Soong, J. Stull, J. Trumper, W. Voges, R.M. Wagner,
R. Wilson
To appear in Astrophysical Journal Letters
We present first results from a multiwavelength campaign to observe the
binary pulsar system Her X-1/HZ Her. The campaign spanned four days during
August 1993: observations were taken with 5 satellites and several ground-based
optical facilities. A substantial, unexpected drop in flux at X-ray energies,
with no change in absorbing column density, was observed. The pulse period has
increased from the previous measurement, contrary to the usual spin-up, and no
pulsed emission is detected above 0.9 keV in the low state. The optical and UV
fluxes continued to show 1.7 day modulation attributed to X-ray heating of the
companion star. However, the UV flux around eclipse was significantly reduced
implying an absence of the normally observed excess attributed to X-ray heating
of the disk. We conclude that we have observed an anomalous low state, seen
only once before (Parmar et al. 1985), in which the X-ray flux is not
redistributed but obscured. We suggest explanations for the behavior of the
flux at different wavelengths.
--------------------------------------------------------------
ASYMMETRIC MASS ACCRETION IN THE MAGNETIC CATACLYSMIC VARIABLE RE1149+28
S.B. Howell, M. Sirk, and R.F. Malina
To appear in Astrophysical Journal [CEA publication #605]
We present the first detailed extreme ultraviolet photometric observations
of a magnetic cataclysmic variable. Our two EUVE observations of the AM Her
star RE1149+28 were obtained about one year apart and show lightcurve
variations on orbital to yearly timescales, as well as long-term mean flux
level changes of a factor of two. The photometric data show a persistent
ingress EUV enhancement which lasts ~0.04 in phase. We attribute this to
a region of ~1e3 km in extent at the accretion impact site, on or very near
the surface of the white dwarf primary. Our observations of RE1149 are
consistent with a relatively low system inclination and provide a best fit
orbital period of 90.14 +/- 0.015 minutes.
Subject headings: Binaries: General -- cataclysmic variables, Stars:
individual (RE1149+28), Accretion, Ultraviolet: Stars
--------------------------------------------------------------
ACTIVE GALAXIES OBSERVED DURING THE EXTREME ULTRAVIOLET EXPLORER ALL-SKY SURVEY
H.L. Marshall, A. Fruscione, and T.E. Carone
To appear in Astrophysical Journal [CEA publication #604]
We present observations of active galactic nuclei (AGN) obtained with the
Extreme Ultraviolet Explorer (EUVE) during the all-sky survey. A total of 13
sources were detected at a significance of 2.5 sigma or better: seven Seyfert
galaxies, five BL Lac objects, and one quasar. The fraction of BL Lac objects
is higher in our sample than in hard X-ray surveys but is consistent with the
soft X-ray Einstein Slew Survey, indicating that the main reason for the large
number of BL Lac objects detected in the extreme ultraviolet (EUV) and soft
X-ray bands is their steeper X-ray spectra.
We show that the number of AGN observed in both the EUVE and ROSAT Wide
Field Camera surveys can readily be explained by modeling the EUV spectra with
a simple power law in the case of BL Lac objects and with an additional EUV
excess in the case of Seyferts and quasars. Allowing for cold matter
absorption in Seyfert galaxy hosts drives up the inferred average continuum
slope to 2.0 +\- 0.5 (at 90% confidence), compared to a slope of 1.0 usually
found from soft X-ray data. If Seyfert galaxies without EUV excesses form a
significant fraction of the population, then the average spectrum of those
with bumps should be even steeper. We place a conservative limit on neutral
gas in BL Lac objects: N_H < 1e20 cm^(-2).
--------------------------------------------------------------
IN-ORBIT PERFORMANCE OF THE SPECTROMETERS OF THE EXTREME ULTRAVIOLET EXPLORER
W. Boyd, P. Jelinsky, D. S. Finley, J. Dupuis, M. Abbott, C. Christian,
and R.F. Malina
To appear in "EUV, X-Ray, and Gamma-Ray Instrumentation for Astronomy V,"
Proceedings of SPIE, 2280, 1994 [CEA publication #603]
The Extreme Ultraviolet Explorer (EUVE), launched on June 7, 1992, is an
extremely successful NASA astrophysics mission that contains three extreme
ultraviolet (EUV) spectrometers designed to be used in pointed spectroscopic
observations of astrophysical sources in the the 70-760 A wavelength region.
The spectrometers utilize a slitless design based on grazing-incidence optics
and variable line-space gratings. Detailed wavelength scales determined from
ground-based calibrations and refined with in-orbit data are used to assign
wavelengths for each detected photon to within half a resolution element (less
than 0.8 A in all cases). Spectral resolving power (FWHM of non-Gaussian
profiles) varies in the range R = lambda/Dlambda ~150-400. Spectrometer
throughputs were determined from an extensive laboratory calibration and then
were adjusted slightly based on in-flight calibration spectra of known
astrophysical continuum sources (hot DA white dwarf stars). We also have
measured count rates from the detector and the geocoronal and distributed
backgrounds, parameters critical to assessment of accurate flux levels from
the astrophysical sources.
--------------------------------------------------------------
LONG-TERM ORBITAL PERFORMANCE OF THE MCP DETECTORS ABOARD THE EXTREME
ULTRAVIOLET EXPLORER
J.V. Vallerga, M. Eckert, M. Sirk, O. Siegmund, and R.F. Malina
To appear in "EUV, X-Ray, and Gamma-Ray Instrumentation for Astronomy V,"
Proceedings of SPIE, 2280, 1994 [CEA publication #602]
The Extreme Ultraviolet Explorer (EUVE), launched June 7, 1992, conducted
an all-sky survey in the extreme ultraviolet wavelengths (70-760 A) for 6
months and is now performing spectroscopic pointings for Guest Observers. The
seven microchannel plate (MCP) detectors used on the instrument (four for
imaging in photometric wavebands and three for the spectrometers) have operated
successfully throughout the mission. The long-term (780 days) performance
characteristics such as quantum efficiency (QE), gain, and background count
rate, will be reviewed along with other interesting unexpected effects noted
during the mission. Because the QE has remained constant, the background has
been reduced, and other effects have been minimized, the EUVE instruments
currently operate better than after launch and will probably continue to do so.
--------------------------------------------------------------
3. CEA Job Listings
===================
by Cathie Jones, CEA Personnel Manager
Programmer Analyst -- Center for EUVE Astrophysics
Job #08-199-10/CP
University of California
NASA Extreme Ultraviolet Explorer Project
Work with a small team of programmers, scientists and engineers, to develop
and maintain the system of ground operations software that analyzes science
data from an astronomical instrument in Earth orbit. Provide software for
telemetry storage and analysis, and instrument monitoring and control. Design
new software and maintain existing software in a C/Unix environment on a
network of Sun workstations and servers. Provide support to programmers
working on innovative technology projects.
Qualifications: Strong background in computer science/software engineering.
Experience in advanced C/UNIX programming and UNIX tools. Ability to work
under pressure.
Combination of the following desired: satellite operations, expert systems,
lisp programming, shell programming, real-time data processing, networks,
innovative technologies for cost-reduction and automation, supervision of
small projects.
Resumes due by 9/23/94. Reference job number on cover letter.
REFERENCES
==========
o Bowyer, S., Lieu, R., Lampton, M., Lewis, J., Wu, X., Drake, J.J., and
Malina, R.F., "The First EUVE Source Catalog", Astrophysical Journal
Supplement, 93(2), 1994 [CEA publication #565]
o Malina, R.F., et al., "The Extreme Ultraviolet Explorer Bright Source List"",
Astronomical Journal, 107(2), 751-764, 1994 [CEA publication #553]
---------------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme Ultraviolet
Astrophysics, University of California, Berkeley, CA 94720, USA. The opinions
expressed are those of the authors. EUVE Principal Investigators and Newsletter
Publishers: Drs. R.F. Malina and C.S. Bowyer. EGO and Archive Science Manger:
C.A. Christian. Archive Manager and Newsletter Editor: B.A. Stroozas. Funded
by NASA contracts NAS5-30180 and NAS5-29298. Send newsletter correspondence
to: ceanews@cea.berkeley.edu. The EUVE project is managed by NASA's GSFC.
The GSFC Project Manager: Paul Pashby, Project Scientist: Dr. Yoji Kondo,
Deputy Project Scientist: Dr. Ronald Oliversen. NASA HQ Program Scientist:
Dr. Robert Stachnik, Program Manager: Dr. G. Riegler. GSFC Project Operations
Director: Mr. Kevin Hartnett. Information on the EUVE Guest Observer Program
is available from: Dr. Y. Kondo, Mail Code 684, GSFC, Greenbelt, MD 20771 at
(301) 286-6247 or e-mail to euve@stars.span.nasa.gov.
END-----------EUVE------------ELECTRONIC---------------NEWS-------------END
% ====== Internet headers and postmarks (see DECWRL::GATEWAY.DOC) ======
% Date: Wed, 14 Sep 1994 16:12:23 -0700
% From: EUVE Electronic Newsletter distribution <ceanews@cea.Berkeley.EDU>
% Message-Id: <199409142312.QAA19759@sdaf1.cea.berkeley.edu>
% To: euvenews@cea.Berkeley.EDU
% Subject: EUVE Electronic Newsletter
% Sender: ceanews@cea.Berkeley.EDU
% Reply-To: ceanews@cea.Berkeley.EDU
|
| 770.46 | Latest EUVE catalogs | MTWAIN::KLAES | No Guts, No Galaxy | Tue Sep 20 1994 16:45 | 326 |
| From: VERGA::US4RMC::"ceanews@cea.Berkeley.EDU" 19-SEP-1994 20:54:31.75
To: egi@cea.Berkeley.EDU, euvenews@cea.Berkeley.EDU
CC:
Subj: New EUVE catalog available
The latest edition of the EUVE sky survey catalog, Appendix F of NRA
94-OSS-13, is now available on the CEA/EUVE ftp site, and via the
World Wide Web. The new catalog supercedes an earlier version which
was made available in August.
The documented listings include positions, count rates for every
bandbass with a detection, a detection quality rating, and possible ID
names for each source in the all-sky survey and deep survey. A list of
other possible detections by EUVE is also supplied.
To get this catalog, obtain either the PostScript file
/pub/nra/Appendix_F.ps or the ASCII file /pub/nra/text/Appendix_F.txt
from the ftp site at:
cea-ftp.cea.berkeley.edu
The EUVE Guest Observer Center
% ====== Internet headers and postmarks (see DECWRL::GATEWAY.DOC) ======
% Date: Mon, 19 Sep 1994 15:09:57 -0700
% From: Anne Miller <annem@cea.Berkeley.EDU>
% To: egi@cea.Berkeley.EDU, euvenews@cea.Berkeley.EDU
% Subject: New EUVE catalog available
% Sender: ceanews@cea.Berkeley.EDU
% Reply-To: ceanews@cea.Berkeley.EDU
From: VERGA::US4RMC::"ceanews@cea.Berkeley.EDU" 20-SEP-1994 03:34:05.43
To: euvenews@cea.Berkeley.EDU
CC:
Subj: EUVE NRA information
Attention,
The following is a message from the EUVE Guest Observer (GO) Center about
the EUVE NASA Research Announcement (NRA) for Cycle 3 of the GO Program. It
is intended for those of you interested in submitting GO proposals. Thanks ...
Brett Stroozas
EUVE Science Archive Manager
----- NRA Message from EUVE GO Center -----
The third EUVE NRA has been mailed out, and should have reached you by
now. This news bulletin contains information on getting the complete
appendices to the NRA, notes on some of the appendices, and on the pro-
cedures for submitting the electronic parts of your proposal.
We recommend you read this bulletin with a copy of the NRA and appendices
and forms, including a current copy of the EUVE Guest Observer Handbook, at
hand. If you have not yet obtained them, read on.
-------------------------------------------------------------------------------
I. GETTING THE COMPLETE APPENDICES TO THE NRA
-------------------------------------------------------------------------------
The NRA mailing includes the announcement and Appendix A, which outlines
the EUVE Guest Observer program. Appendices B-H can be obtained either:
1) electronically, using the WWW URL or ftp site given on the last page
of the Announcement, or
2) in hardcopy by request to the Project Office at GSFC.
Although the email address for the GO Center is listed under
"E_MAIL REQUESTS FROM:" on page 2 of the Announcement, mail to this address
will generally be answered with information on using the electronic facilities
(also given below in this bulletin), or redirected as requests for paper
copies to the EUVE Project Office at GSFC.
1.A ELECTRONIC COPIES VIA WORLD WIDE WEB
-------------------------------------------------------------------------------
If a WWW browser such as Mosaic or Lynx is available to you, this is
the easiest way to obtain the NRA materials. Use your Web client
program to open the URL for the Center for EUV Astrophysics (CEA):
http://www.cea.berkeley.edu/HomePage.html
and select the icon for the EUVE Guest Observer (EGO) Center. Select the
link "NRA" to enter a "shopping page". Click on one of the underlined links
to order your file selection and a transfer will be initiated. A dialog box
will appear for you to enter the directory where you want the file. This
process can repeated for each file, or you can get the entire NRA in a single
compressed tarfile.
If you do not have access to a WWW client, you can get the NRA materials
from the WWW using telnet:
%telnet cea-ftp.cea.berkeley.edu 200
A session in Lynx, the text-based Web browser, will be started automatically
at CEA. You must first specify your terminal type; enter the default, for a
VT100, by typing a return. This works pretty well for most terminals, including
xterms. You will be given a menu that represents the CEA HomePage. Select
"NASA Research Announcemnet for EUVE Guest Observer Program," by pressing the
down-arrow (2 on the keypad) until it is highlighted, and press return. This
will put you on the NRA "shopping page." You can open and read any ASCII file,
such as the electronic "proposal form" file, by selecting it with the down-
arrow, and typing a return. If you want a copy, select the filename and type
"p" for print. A page with printing options allows you to mail the selected
file to yourself. This method of receiving the NRA files is subject to limita-
tions on the size of email messages.
1.B ELECTRONIC COPIES VIA FTP
-------------------------------------------------------------------------------
The Appendices for NRA 94-OSS-13 may be obtained via anonymous ftp at the
CEA. The site addres is:
cea-ftp.cea.berkeley.edu
OR
128.32.154.12
Use the following procedure to extract files containing the NRA materials
via ftp:
%ftp cea-ftp.cea.berkeley.edu
Log on with username ANONYMOUS;
the password is your COMPLETE EMAIL ADDRESS.
Set the file transfer mode to binary:
%binary
Go to the nra directory:
%cd /pub/nra94
There is a README file with further instructions.
To get a copy, type:
%get README
To get a compressed tarfile with the complete NRA type:
%get NRA.tar.Z
Note: Your site may be set up to uncompress the file
"on the fly".
The appendices are also available in smaller separate files.
ASCII versions of most files are now available. Figures for Appendix G must
be requested. Send postal mail address to egoinfo@cea.berkeley.edu.
If you have difficulty with the ftp site or technical questions in
regard to instrument performance, please contact the EGO Center by
sending e-mail or calling:
egoinfo@cea.berkeley.edu
(510) 643-5056
1.C PAPER COPIES OF NRA APPENDICES
-------------------------------------------------------------------------------
If you wish to receive paper copies of the NRA Appendices via postal mail,
OR, you have a specific question in regard to the NRA or the EUVE project
please contact:
Dr. Yoji Kondo
EUVE Project Scientist
Code 684
Goddard Space Flight Center
Greenbelt, Md. 20771
(301) 286-6247
You can send your request via email to:
euve@stars.nasa.gsfc.gov.
-------------------------------------------------------------------------------
II. PROCEDURES FOR ELECTRONIC SUBMISSION
Certain parts of the proposal must be submitted in both electronic and paper
versions. These include the Cover Page, General Form, and Target Summary Form,
with the addition, for spectroscopy proposals, of a sample signal-to-noise
calculation for one of the proposed targets. Copies of these forms which have
been obtained electronically are acceptable for both paper and electornic
submission. A copy of only the electronic forms may be obtained as the file
"Forms.txt" from the CEA anonymous ftp site.
NOTES TO PROSPECTIVE PROPOSERS
@ Item 3 does not mention the necessity of including a sample signal-to-noise
calculation with electronic submissions for spectrometer observations.
Notes on Appendix C:
@ Section I, page C-2: the electronic submission must include copies of
the Cover Page, General Form, Target Summary Form, and for spectrometer
proposals, a sample signal-to-noise calculation (worksheet in Appendix D).
The table on C-1 only mentions electronic submission for the Target Summary
Form. The signal-to-noise calculation need not be submitted electronically
for proposals that use only the Deep Survey and/or Scanner instruments
(including RAP). These proposals DO require a Technical Justification.
@ Section IV, "moving target": a moving target is one that is close enough
that the spacecraft cannot track it continuously, but must make frequent
(>= 1 per orbit) updates. These include the moon, planets, and comets.
The ephemeris provided in the Special Requirements section should give
the object's position at a resolution of 1 per day for comets and the moon,
and 1 per 3-5 days for planets. This ephemeris is used only for determining
whether EUVE can observe the target during the specified period.
@ Section V, TECHNICAL JUSTIFICATION, the sample calculation required for
electronic submission is a signal-to-noise calculation, as summaraized in
the worksheet at the end of Appendix D. The Technical Justification need
not be submitted electronically, although the worksheet appears on a page
labeled "TECHNICAL JUSTIFICATION FORM".
@ In section X, RIGHT ANGLE PROGRAM SUBMISSION, the phrase "no observing re-
quirements allowed" refers to special pointing requirements. Right Angle
Program proposers may not specify spacecraft roll angle, coordinated
observations, request phase coverage or contiguous observing time.
@ As stated, in section X, a RAP proposal may be submitted electronically,
in its entirety. Science Justifications should only be submitted elec-
tronically as part of a RAP proposal. RAP proposals DO NOT require a
Technical Justification.
Notes on Appendix D:
@ The form for electronic submissions is an electronic form, available as an
ASCII file via ftp or email as inticated on page D-1. The file also in-
cludes spaces for a Budget Summary and Institutional Endorsements, which
are not actually required for the electronic submission. These portions
of the file may be used to produce the corresponding parts of the hardcopy
forms.
SAMPLE S?N CALCULATION
Notes on the individual items in the "INSTRUCTIONS FOR SAMPLE CALCULATION"
The calculations in the sample S/N worksheet correspond to equations in
the EGO Program Guest Observer Handbook, although the nomenclature used
is somewhat different. To clarify the correspondences, the equation numbers
from the Handbook, and the labels from the Quick Reference section at the end
of Chapter 3, are given below each item where applicable, with any notes.
Underscores in Handbook references indicate subscripts. The word "script"
before a letter indicates the use of the script style typeface for variables
in the Handbook.
@ Units for Target_HI_Column and Target_HeI_column are cm^-2.
@ Effective_Area: Spectrometer channel effective area, in cm^2.
Handbook: A_eff(lambda)
@ Target_Flux: Model source flux at spectrometer aperture, after ISM
absorption.
Handbook: script F(lambda)
@ Target_Exposure: integration time. Note that required units for
the sample calculation are kiloseconds.
Handbook: script T. All times in in the Handbook are in seconds.
@ Target_Bin_Width: w, spectral bin width in Angstroms. The typical bin width
for emission lines is the spectrometer channel resolution element: .5 A for
SW, 1.0 A for MW, and 2.0 A for LW.
@ Background_Count_Rate: Background count rate in a spectral bin. Averaging
over the sample height of of the background area is implied. See
the Guest Observer Handbook or the data files available via WWW or
ftp for estimates
of instrument background count rates. The rates given are per Angstrom, and
must be multiplied by the bin width to obtain the count rate in a spectral
bin.
Handbook: B' = script B x w (eq. 3-4).
Note: paper copies of Appendix D acquired from the Project office may have
an overtyped line for this entry in the sample calculation instructions.
The explanation for this entry should read: "Expected background count rate
(photons/sec), integrated over the bin width."
@ Source/Bkgd_Height_Ratio: This is the ratio of the height (perpendicular
to the dispersion direction) of the projected spectrum aperture to the
height of the background region used for subtraction. This parameter may
not be applicable for diffuse or extended sources; see GO Handbook
sections 3.6.2 and 3.10.
Handbook: 1/n, using same definitions (section 3.6.2, eq. 3-3)
@ Total_Signal: S, total source counts in a spectral bin after integration
over time T.
Handbook: Equivalent to the Handbook's source count rate, S', multiplied
by exposre, script T. See equation 3-1 for line emission count rates,
equation 3-2 for continuum bin count rates.
@ Total_Noise: standard deviation of integrated source signal. Units are
counts.
Handbook: sigma_S. See Hanbook equation 3-6.
@ Achieved_Signal/Noise, also called signal-to-noise ratio, for line or
continuum bin.
Handbook: This quantity is equivalent to S/sigma_S in equation 3-9 for
emission lines, 3-10 for continuum bins. Definitions of S and B in Ap-
pendix D include multiplication by the bin width where necessary for
continuum sources, while these multiplications are explicit in the
Handbook S/N equations.
Notes on Appendix F:
A new version of the latest EUVE sky survey catalog is now available on the
CEA/EUVE ftp site.
% ====== Internet headers and postmarks (see DECWRL::GATEWAY.DOC) ======
% Date: Sat, 17 Sep 1994 15:54:08 -0700
% From: Brett Stroozas <bretts@cea.Berkeley.EDU>
% To: euvenews@cea.Berkeley.EDU
% Subject: EUVE NRA information
% Sender: ceanews@cea.Berkeley.EDU
% Reply-To: ceanews@cea.Berkeley.EDU
|
| 770.47 | EUVE Newsletter Vol 4, No. 10 | 56821::BATTERSBY | | Thu Oct 20 1994 16:07 | 567 |
| Article: 6564
From: bretts@sunset.cea.berkeley.edu (Brett Stroozas)
Newsgroups: sci.astro,sci.space.tech,sci.space.science,sci.space.news
Subject: EUVE Electronic Newsletter
Date: 18 Oct 1994 22:47:00 GMT
Organization: Center For Extreme Ultraviolet Astrophysics
EEEEEEEEEEE U U V V EEEEEEEEEEE
E U U V V E
E U U V V E
EEEEEEE U U V V EEEEEEE
E U U V V E
E U U V V E
EEEEEEEEEEE UUUUU V EEEEEEEEEEE
---------------------------------------------------------------------------
ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
---------------------------------------------------------------------------
Vol 4, No. 10 18 Oct 1994 ISSN 1065-3597
---------------------------------------------------------------------------
Notes from the Editor
=====================
by Brett A. Stroozas, EUVE Data Archive and Science Support (DASS) Manager
Welcome to the electronic newsletter for NASA's Extreme Ultraviolet Explorer
(EUVE) satellite, which is compiled and published monthly by the EUVE Science
Archive group at the Center for EUV Astrophysics (CEA) in Berkeley, CA. The
EUVE observatory performed well throughout the month of September, completing
observations of the following Guest Observer (GO) targets (spectral types,
taken from the SIMBAD or internal CEA databases, are indicated in parentheses):
CF Tuc (G3:V+), FK Aqr (M0Vpe), HD220657 (F8IV), MCT0027-6341 (WD), WD0050-332
(WD), and the Moon. A daytime observation test was conducted on the target
V711 Tau (G9V).
The contents of this issue of the EUVE electronic newsletter are as follows:
1. NASA Administrator Dr. Dan Goldin Comments on EUVE
2. Education Outreach at CEA
3. Mission Operations Innovation at CEA
4. Recent EUVE Science Highlights
5. Notes from the EUVE Guest Observer Center
5.1 ISM Column Densities and Extinction
5.2 Scanner Backgrounds
5.3 Scanner/Deep Survey Calibration Data
6. Notes from the EUVE Science Archive
6.1 New Services Available via the World Wide Web
6.2 GO Data Release List for 1 November 1994
6.3 Accessing the Archive
7. Abstracts of Recently *Accepted* EUVE Papers
To comment on or make suggestions for the EUVE electronic newsletter, please
send e-mail to ceanews@cea.berkeley.edu (Internet).
1. NASA Administrator Dr. Dan Goldin Comments on EUVE
=====================================================
In a talk entitled "The Next Frontier" given on 19 Aug 1994 at the
Commonwealth Club of California in San Francisco, NASA Administrator
Dr. Dan Goldin had the following glowing comments regarding the EUVE
mission:
"And in fact today, Roger Malina, who is at the head table walked
up to me ... he is from UC Berkeley, and he said "Mr. Goldin, let
me tell you, you cut our budget on the EUVE program" ... that's the
Extreme Ultraviolet Explorer program ... it's an Astrophysical
program ... "and we're cutting into the mission operations and
data analysis budget!" If we want to start new things, we can't
keep having people employed operating the old things where the
operating budget keeps going up ... so he said "let's just cut the
operating budget!" So what he did was -- he employed artificial
intelligence and expert systems and, instead of having three shifts
operating the spacecraft, with people going around the clock, he
changed the paradigm ... Less is more, and we're getting more
reliable operations of the spacecraft with one shift instead of
three."
The audio recording of the above text is accessible electronically from the
CEA World Wide Web (WWW) Home Page (http://www.cea.berkeley.edu).
2. Education Outreach at CEA
============================
by Dr. Isabel Hawkins, CEA Education Outreach Coordinator
With funding from NASA's Astrophysics Division, CEA is sponsoring an
eight-month K-12 education outreach demonstration project. "Science On-Line
(SOL) -- Earth and Space Science for the Classroom" began in September 1994
and links together formal and informal science centers, each of them having
unique and complementary assets. The project joins the efforts of CEA, the
Lawrence Hall of Science and the U.C. Museum of Paleontology, with San
Francisco's Exploratorium, and Chicago's Adler Planetarium for the purpose
of coordinating on-line resources that respond to the needs of K-12 teachers,
students, and the general public. The project will result in coordinated
resources available through the WWW with Mosaic, including virtual museums,
NASA mission information and data, and teacher-developed lesson plans that make
use of the unique aspects of the Internet. This pilot project is a precursor
to an overarching effort entitled "Science Information Infrastructure (SII)"
which will link the Nation's science museums with research institutions to
bring coordinated resources to the K-12 and general public communities. The
SII has received partial funding from the High Performance Computing and
Communications division of NASA, and partners the Center for EUV Astrophysics
and the Smithsonian Astrophysical Observatory with the Exploratorium, Lawrence
Hall of Science, UC Museum of Paleontology, Smithsonian National Air and Space
Museum, Science Museum of Virginia, Chicago's Adler Planetarium, New York Hall
of Science, Boston Museum of Science, and the Earth Observing Satellite
Company. These projects are designed to make certain that as schools gain
access to the information superhighway, K-12 educators and students will find
appropriate resources that respond to their particular needs.
3. Mission Operations Innovation at CEA
=======================================
The EUVE Science Operations Center (ESOC) is working to complete development
and testing for single-shift 10-hour daily operations. An internal readiness
review was held at CEA on 5 October to judge the readiness of the ESOC to
move from the current triple-shift, 24-hour-a-day coverage to a single-shift
scenario without increasing the risk to the mission requirements. The panel
recommended that the ESOC proceed after meeting the self-imposed internal
criteria and after obtaining Goddard Space Flight Center (GSFC) Project Office
sign-off.
On another front, the EUVE operations test-bed team has completed evaluation
of the Jet Propulsion Laboratory's Spacecraft Health Inference Engine (SHIE).
The test-bed continues to host NASA Missions interested in low-cost operations.
Hubble Space Telescope and Lockheed support personnel visited CEA to view the
"E-works" implementation that will autonomously monitor science payload health
and safety and current test-bed activities. The SOFIA project from NASA Ames
Research Center visited CEA to investigate similarities in mission concepts that
may prove to be test-bed areas.
4. Recent EUVE Science Highlights
=================================
by Dr. Antonella Fruscione, EUVE Scientist
The following are recent science highlights from the EUVE mission:
* The detection of an ancient (5 billion years old) milli-second pulsar with
the Deep Survey Telescope during Guest Observer observations. Because old
neutron stars are expected to have cooled to non-EUVE emitting temperatures,
detection of this one indicates that highly energetic re-heating has taken
place. These observations are used to discriminate between a diverse array
of standard and exotic re-heating mechanisms, and also to elucidate the
ionization state of the interstellar medium along the path to the star
(Edelstein, et al.).
* The light curve of the intermediate polar cataclysmic variable EX Hya shows
clear evidence for eclipses by the secondary star and also by the accretion
stream. There is modulation at the white dwarf rotation period. Most of
the EUV flux probably arises in the "accretion curtain" or region between
the innermost radius of the accretion disk and the white dwarf itself, where
material begins to follow the magnetic field lines rather than rotate in
Keplerian fashion (Hurwitz, et al.).
* The paper "A SPECTROSCOPIC MEASUREMENT OF THE CORONAL DENSITY OF PROCYON"
by Schmitt, Haisch, and Drake has just come out as a report to the journal
Science (Vol. 265, pp. 1420-22). The main result is that using the ratio
of two Fe XIV lines at 211.32 and 264.79 A, the authors determined a density
of 4-7E+09 electrons/cm^3 -- a factor of 2-3 higher that in typical solar
active regions. This is the first direct measurement of the coronal density
in another solar-like star. From this value the authors estimated that
about 6% of the stellar surface is covered by about 7E+04 loops.
5. Notes from the EUVE Guest Observer (EGO) Center
==================================================
by Anne Miller, EGO Technical Writer
The following sections provide relevant information to those researchers
who have proposed in Cycle 3 of the GO Program for Scanner and Deep Survey
imaging observations.
5.1 ISM Column Densities and Extinction
---------------------------------------
For help in estimating interstellar medium (ISM) column densities and
extinctions, researchers may use the tools provided on the EGO Center WWW Home
Page via the URL http://www.cea.berkeley.edu/ego/HomePage.html. Click on the
highlighted text "ISM Hydrogen Column Density Search Tool" to use a routine
that provides several of the nearest measured ISM columns for a given position.
Click on the text "ISM" to run a program that computes the transparency of the
ISM using a commonly used model which only requires a few input parameters.
The C source code for the ISM program may also be obtained from the CEA
anonymous ftp site (ftp.cea.berkeley.edu; /pub/archive/software/ism).
5.2 Scanner Backgrounds
-----------------------
To estimate background levels for the Scanner telescopes, researchers may
use the CEA WWW "Count-Rate Request Form" from the Survey Home Page (URL above)
to obtain a data file for some sky location near their target, in which no
sources were detected. After clicking on the "Count-Rate Request Form" box in
the Home Page, read the instructions and complete the form with an RA and Dec,
using a search radius of 0.05 degrees and a confidence limit of 3.0 sigma.
The counts in each survey band-pass will be computed from survey skymaps and
will be delivered via e-mail. The flux is reported in counts/(arc minute)^2,
and the file includes a significance factor derived from chi-squared statistics.
Check the significance before using the flux as a background estimate; the
value should be less than 9.0 to insure that no sources were actually found
within the search radius.
5.3 Scanner/Deep Survey Calibration Data
----------------------------------------
Calibration data on the Scanner and Deep Survey instruments is available
by means of the CEA WWW URL (http://www.cea.berkeley.edu; click on "EUVE Survey
Home Page") or via the CEA anonymous ftp site (ftp.cea.berkeley.edu;
/pub/archive/survey/calibration_data). The available calibration data includes
effective areas, point-spread-functions, and vignetting maps. The files and
limited documentation are available separately, together, or as a single UNIX
TAR-format file.
6. Notes from the EUVE Science Archive
======================================
by Brett Stroozas, Archive Manager
6.1 New Services Available via the World Wide Web (WWW)
-------------------------------------------------------
Two new services are now available to researchers via the CEA WWW Home Page
(http://www.cea.berkeley.edu under Archive/Data). The first is a revised
version of the spectral browser which allows users to browse and retrieve
public EUVE 1-d spectra. The new revised version is much easier to use as
it allows one to search the data by spectral type and/or position. Additional
search options will soon be available.
The second new service is the availability of the published EUVE source
catalogs on the WWW via NASA's Astrophysics Data System (ADS) catalog service.
The ADS catalog service, which has recently come into operation on the WWW,
offers users with most of the capabilities of the classical ADS catalog service
but with much improved speed and ease of use. The available EUVE catalogs are
the following:
o euve_bsl -- "The Extreme Ultraviolet Explorer Bright Source List" (Malina,
et al. 1994)
o euve_cat1 -- "The First EUVE Source Catalog" (Bowyer, et al. 1994)
o euve_cat1supp -- supplement table (Table 7) to "The First EUVE Source
Catalog" (Bowyer, et al. 1994)
o euve_rap1 -- "Serendipitous EUV Sources Detected during the First Year of
the Extreme Ultraviolet Explorer Right Angle Program" (McDonald, et
al. 1994)
The ADS catalog service may be accessed directly via the URL
http://adswww.harvard.edu/catalog_service.html
or through the Archive/Data section of the CEA Home Page.
6.2 GO Data Release List for 1 November 1994
--------------------------------------------
The table below lists the GO observations which become public on 1 November
1994; all have been reprocessed with the most recent versions of the EGO Center
software and reference data. For each entry is given the target name, the
approximate exposure time in kiloseconds, the GMT start and end date(s) for
the observation, the spectral type of the target, and the data identification
code. All public data sets may be ordered from the archive via WWW and
electronic or postal mail (see addresses below). Please be sure to include
in your order the DataID(s) of interest.
The data rights policy for GO observations states that GO's have proprietary
rights to the data for one year from the date (s)he receives it. It is often
the case that long observations are broken up over many months; e.g. an
observation approved for 60 ksec may actually be observed for 10 ksec one
month, 20 ksec the next and 30 ksec three months later. In such cases the
one-year proprietary period begins after the GO receives the final piece of
the complete observation.
===============================================================
Target ~Exp Observation Date(s) SpT DataID
Name (ksec) Start End
===============================================================
Data Sets Available 1 Nov 1994:
AM_HER 136 Sep 23 1993 - Sep 28 1993 CV go0106
AR_LAC 90 Oct 12 1993 - Oct 15 1993 G2IV go0107
HD7672 84 Sep 28 1993 - Oct 1 1993 G5 go0108
HR1099 81 Sep 16 1993 - Sep 19 1993 G+K go0109
HR1099 36 Sep 19 1993 - Sep 20 1993 G+K go0110
HR1099 32 Sep 20 1993 - Sep 21 1993 G+K go0111
LAMBDA_AND 90 Oct 16 1993 - Oct 19 1993 G8 go0112
R_AQU 60 Aug 31 1993 - Sep 2 1993 M7 go0113
RE1938-461 27 Aug 16 1993 - Aug 17 1993 CV go0114
RE1938-461 124 Oct 6 1993 - Oct 10 1993 CV go0115
===============================================================
6.3 Accessing the Archive
-------------------------
Listed below are the various methods for accessing EUVE archival material:
o CEA World Wide Web URL:
http://www.cea.berkeley.edu (Mosaic/lynx remotely)
telnet www.cea.berkeley.edu 200 (lynx locally at CEA)
o NASA's Astrophysics Data System:
http://adswww.colorado.edu/adswww/adshomepg.html (Mosaic/lynx)
o CD-ROM Series: Volumes 1.1, 2.1, and 2.2 (seven separate CDs) available
o e-mail: archive@cea.berkeley.edu
o anonymous FTP (or gopher): ftp.cea.berkeley.edu
o EUVE Electronic Newsletters:
Subscriptions: majordomo@cea.berkeley.edu ("subscribe euvenews")
Post message to all subscribers: euvenews@cea.berkeley.edu
o Postal Mail:
The EUVE Public Science Archive
Center for EUV Astrophysics
2150 Kittredge St.
Berkeley, CA 94720
510-642-3032 (voice) or 510-643-5660 (fax)
archive@cea.berkeley.edu
7. Abstracts of Recently *Accepted* EUVE Papers
===============================================
Included below are abstracts of EUVE-related papers recently *accepted*
for publication. For those papers authored by CEA scientists, the EUVE
publication numbers are indicated. Unless otherwise noted, researchers may
obtain preprints of CEA papers by sending an e-mail request containing the
publication number(s) of interest to pub@cea.berkeley.edu.
Researchers are encouraged to contribute *accepted* EUVE-related abstracts
for inclusion in future editions of this newsletter; abstracts or full papers
will also be posted under the CEA WWW Home Page. Please send all abstracts
or papers to archive@cea.berkeley.edu.
--------------------------------------------------------------
THE OPTICAL THICKNESS OF STELLAR CORONAE IN EUV LINES
C.J. Schrijver, G.H.J. van den Oord, and R. Mewe
Astronomy & Astrophysics, 1994, 289, L23-L26
Stellar coronae are commonly assumed to be optically thin. Recent
spectroscopic observations in the EUV, however, lead us to question the
validity of this approximation for strong lines. We argue that scattering
may significantly affect the strongest coronal lines in coronae composed of
magnetic loops, possibly embedded in a hot stellar wind. Even if the average
number of scatterings per photon in some coronal lines is only of order unity,
the relative line strengths and the line-to-continuum ratio can be significantly
affected in non-symmetric inhomogeneous atmospheres: photons in weak lines
and in the optically thin continuum escape without any scattering, but strong
lines can be weakened or enhanced depending on the balance between outward
traveling line photons that are scattered back toward the stellar surface (if
not lost by branching), there destroyed by absorption, and downward traveling
line photons that are scattered upward and escape. We draw attention to the
fact that line scattering due to the non-negligible optical thickness in strong
coronal lines can have severe implications for differential emission measure
models and for abundance and density determinations, while it may serve as a
diagnostic for the existence of tenuous hot winds.
Keywords: Line: formation, Radiative transfer, Scattering, Stars: coronae,
X-rays: stars
--------------------------------------------------------------
EUV SPECTROSCOPY OF COOL STARS; I. THE CORONA OF ALPHA CEN OBSERVED WITH EUVE
R. Mewe, J.S. Kaastra, C.J. Schrijver, G.H.J. van den Oord, F.J.M. Alkemade
To appear in Astronomy & Astrophysics
We perform an emission measure analysis of spectra of the coronae of the
cool star binary alpha Cen (A: HD 128620 (G2V) + B: HD 128621 (K1V)) as
observed with the Spectrometers of the Extreme Ultraviolet Explorer (EUVE).
These observations, covering the wavelength range of 60E up to 800E with a
resolution of lambda/Delta-lambda ~160-320, constrain the coronal temperature
structure between about 1E+05 Kelvin up to roughly 10 million Kelvin, while
some additional line and continuum information is available to extend that
coverage from several tens of thousands of Kelvin up to several tens of
millions of Kelvin, although the solution is ill constrained in the extended
range. We performed a re-calibration of the wavelength scale for each of the
three instrumental pass-bands by comparing the model list of emission lines
with the spectrum of alpha Cen, combined with spectra of eight other cool
stars. The high signal-to-noise ratio of the alpha Cen spectrum yielded
indications for a Lorentzian rather than a Gaussian line profile for the MW
passband. The observed spectrum was decomposed into a linear combination of
spectra emitted by isothermal plasmas in thermal equilibrium, using the SPEX
plasma emission code developed in Utrecht. The resulting differential emission
measure distribution shows: a) emission from plasma below ~5 MK with a broad
peak around ~3 MK and with a tail extending down to about 0.5 MK, b) very
little emission from plasma between 0.1 MK and 0.5 MK, c) emission from plasma
below 0.1 MK, and d) possibly a hot component exceeding several tens of million
of Kelvin which, however, may (in part) have another origin than a hot coronal
plasma component. We propose that the hot component may be an artifact of the
corona being close to unit optical thickness for scattering in the strongest
spectral lines, so that part of the line photons can be destroyed by being
scattered towards the stellar surface while the plasma remains optically thin
for continuum photons. Electron density diagnostics based on Fe X, Fe XII,
Fe XIII, and Fe XIV lines, yields values in the range 2-20E+08 cm-3 at T = 1-2
MK.
Keywords: stars: coronae, X--rays: stars, stars: activity, stars:
late--type, stars: abundances, stars: individual: alpha Cen
--------------------------------------------------------------
MASS-RADIUS RELATIONS FOR LOW MASS WHITE DWARFS WITH HELIUM AND CARBON
INTERIORS
S. Vennes, G. Fontaine, and P. Brassard
To appear in Astronomy & Astrophysics Research Notes [CEA publication #607]
We have computed static mass-radius relations for low-mass white dwarfs
defined by surface gravities in the range g = 1E+07 - 1E+08 cm/s^2. We have
assumed pure helium interiors without a hydrogen envelope and carbon interiors
with and without a hydrogen envelope. Surface boundary conditions also assume
non-zero effective temperatures at 49,000 <= T_eff <= 61,000 K. Although
generally applicable to isolated low-mass white dwarfs, these models are
particularly interesting for the interpretation of the class of low-mass He
white dwarfs that potentially emerge from close binary evolution. We discuss
in particular the case of Feige 24 for which Vennes & Thorstensen (1994a) have
proposed a low mass and large radius based on their gravitational redshift
measurement. The binary parameters of Feige 24 are consistent with the
population of He white dwarf + red dwarf close binaries predicted by theory
but also with a population having a more common carbon interior with a thick
hydrogen envelope. We demonstrate that a thin hydrogen layer is unlikely.
Keywords: stars: binaries -- white dwarfs -- interiors -- evolution
--------------------------------------------------------------
A VOLUME-LIMITED SURVEY OF HIGH GALACTIC LATITUDE PLANETARY NEBULAE WITH THE
EXTREME ULTRAVIOLET EXPLORER
Antonella Fruscione, Jeremy J. Drake, Kelley McDonald, and Roger F. Malina
To appear in Astrophysical Journal [CEA publication #609]
We present the results of a complete survey, at extreme ultraviolet (EUV)
wavelengths (58-234 A), of the high galactic latitude (|b| >= 20 deg) planetary
nebulae (PN) with at least one determination of the distance within 1 kpc of
the Sun. The sample comprises 27 objects observed during the Extreme
Ultraviolet Explorer (EUVE) all-sky survey and represents the majority of PN
likely to be accessible at EUV wavelengths. Six PN (NGC 246, NGC 1360, K 1-16,
LoTr 5, NGC 4361, and NGC 3587) were detected in the shortest EUV band (58-174
A). A seventh PN (NGC 6853), not included in the sample, was also detected
during the survey. The emission is consistent in all cases with that of a
point source, and therefore is most probably originating from the PN central
star. Accurate EUV count rates or upper limits in the two shorter EUVE bands
(centered at ~100 and 200 A) are given for all the sources in the sample.
NGC 4361 and NGC 3587 are reported here for the first time as sources of EUV
radiation. As might be expected, attenuation by the interstellar medium
dominates the PN distribution in the EUV sky.
--------------------------------------------------------------
A FIRST LOOK AT THE ELEMENTAL COMPOSITION OF STELLAR CORONAE: ABSENCE OF
THE FIP EFFECT IN THE CORONA OF PROCYON
J.J. Drake, J.M. Laming, K.G. Widing, J.H.M.M. Schmitt, B. Haisch, and S. Bowyer
To appear in Science [CEA publication #610]
The chemical composition of the Sun has been studied extensively over many
years. In recent years it has been discovered that the chemical composition
of the solar corona is not the same as that of the underlying photosphere.
Elements with a first ionization potential (FIP) <= 10 eV (e.g., Fe, Mg, Si,
Ca) are observed to be enhanced relative to those with FIP >= 10 eV (e.g.,
O, Ne, S) in the corona by factors of 3-10 with respect to the photosphere.
This phenomenon is now known as the "FIP Effect." The mechanism responsible
for it is currently unknown. Is the Sun unique, or do other stellar coronae
share a solar-like enhancement of low FIP species? Prior to the recent launch
of the Extreme Ultraviolet Explorer Satellite (EUVE) the spectroscopic
capability required to answer this question did not exist. Based on
spectroscopic observations of the corona of the nearby F5 IV star Procyon
obtained with EUVE, we have now made the first estimates of the relative
abundances of high and low FIP species in the corona of a star other than the
Sun. The results indicate that, in contrast to the Sun, the FIP effect is not
present in the corona of Procyon. The FIP effect is, therefore, not an
ubiquitous feature of late-type stellar coronae. Whether the prevailing
stellar situation is that of the Sun or that of Procyon is of fundamental
interest to the physics of stellar outer atmospheres and also has a bearing
on the origin of cosmic rays.
--------------------------------------------------------------
STELLAR CORONAL ABUNDANCES II: THE ABSENCE OF THE FIP EFFECT IN THE CORONA
OF PROCYON
J.J. Drake, J.M. Laming, and K.G. Widing
To appear in Astrophysical Journal [CEA publication #611]
We present a detailed study of element abundances in the corona of Procyon
based on spectroscopic observations obtained with the Extreme Ultraviolet
Explorer Satellite (EUVE). Emission measures (EMs) have been derived from
observed line fluxes for the elements O, Ne, Mg, Si, S, Ar, Fe and Ni, using
the most recent atomic data. The slope of the resulting EM distribution is
very similar to the well-known result of 1.5 (EM ~ T^(3/2)) found for the solar
corona for log T=5.3-6.0. The abundances in the corona of Procyon are found
to be consistent with their photospheric values. No enhancement of species
with low first ionization potentials (FIP) is observed, such as is the case
for the solar corona: the "FIP effect" appears to be absent in Procyon. We
speculate that the dominant emission from the corona and transition region in
Procyon could originate in low altitude structures analogous to the solar
supergranulation network, which does not appear to exhibit a FIP effect. A
considerable body of observational evidence suggests that Procyon is both a
"basal" star in terms of its chromospheric activity, and is on the spectral
type boundary which separates stars which exhibit activity levels correlated
with rotation and those which do not. Such stars are thought by some workers
to sustain coronae which are heated predominantly by acoustic means. We also
note that an acoustically heated outer atmosphere might not possess sufficiently
small structures to support a fractionation of elements with respect to FIP.
Our results demonstrate that the FIP effect is not an ubiquitous feature of
late-type stellar coronae. Consequently, speculations in the literature that
the FIP effect observed in cosmic rays is a result of their originating from
seed particles injected by late-type stellar coronae must await observational
confirmation that the FIP effect does indeed operate on M dwarfs, which are
likely to be the dominant particle injection source.
--------------------------------------------------------------
FIRST SPECTRAL OBSERVATIONS OF THE DIFFUSE BACKGROUND WITH THE EXTREME
ULTRAVIOLET EXPLORER
P. Jelinsky, J.V. Vallerga, and J. Edelstein
To appear in Astrophysical Journal [CEA publication #612]
We present the first results from the analysis of the spectroscopic
observations of diffuse extreme ultraviolet (EUV) emission taken with the
Extreme Ultraviolet Explorer (EUVE) spectrometers in the wavelength range of
160-740 A. Though not designed or optimized for diffuse observation, the
EUVE spectrometers are the most sensitive diffuse EUV spectrometer in orbit.
The spectral resolution for diffuse emission of the Medium and Long Wavelength
spectrometers are 17 and 34 A FWHM, respectively. During the period from 1992
July 25 to 1992 August 19, the spectrometers surveyed a 2.0 deg x 20 deg field
scanned from (l^II, b^II) = (24 deg, -28 deg) to (44 deg, -47 deg) with a total
effective exposure time of 575,232 s. The only emission lines detected were
those of HeI and HeII (584, 537, and 304 A) with intensities consistent with
local geocoronal and/or interplanetary scattering of solar radiation (584 A =
1.30 Rayleighs; 537 A = 0.040 R; and 304 A = 0.029 R).
Models of the soft X-ray background, which results from a 1E+06 K plasma
(Local Bubble) surrounding the neutral gas near the Sun (Local Cloud), predict
that most of the flux from the hot plasma appears as emission lines in the EUV.
We have compared these spectral predictions with our observations to place
limits on the emission measure vs. temperature of the proposed hot plasma.
Using the same plasma model, we derived emission measures for our data and the
C and B soft X-ray bands of the Wisconsin rocket survey. We find that our
limits for the plasma emission measure are a factor of 5 to 10 below the C and
B band emission measures over the temperature range from 1E+05.7 to 1E+06.4 K.
We explore possible scenarios that could reconcile our results with the X-ray
surveys and conclude that depletion or a non-equilibrium plasma state rather
than absorption are the more likely explanations of the discrepancy. We also
show that our spectrum is inconsistent with the spectrum from the ~1E+05 K gas
at the conductive interface between the hot Local Bubble and the cooler Local
Cloud given by Slavin (1989). In addition, we place new limits on the helium
ionization parameter in the Sun's vicinity caused by the 1E+06 K plasma in the
Local Bubble.
--------------------------------------------------------------
REFERENCES
==========
o Bowyer, S., Lieu, R., Lampton, M., Lewis, J., Wu, X., Drake, J.J., and
Malina, R.F., "The First EUVE Source Catalog", Astrophysical Journal
Supplement, 93(2), 569, 1994 [CEA publication #565]
o Malina, R.F., Marshall, H.L., Antia, B., Christian, C.A., Dobson, C.A.,
Finley, D.S., Fruscione, A., Girouard, F., Hawkins, I., Jelinsky, P.,
Lewis, J., McDonald, J., McDonald, K., Patterer, R.J., Saba, V.,
Sirk, M.M., Stroozas, B.A., Vallerga, J.V., Vedder, P.W.,
Wiercigroch, A., and Bowyer, S., "The Extreme Ultraviolet Explorer
Bright Source List", Astronomical Journal, 107(2), 751-764, 1994
[CEA publication #553]
o McDonald, K., Craig, N., Sirk, M.M., Drake, J.J., Fruscione, A., Vallerga,
J.V., and Malina, R.F., "Serendipitous EUV Sources Detected during the
First Year of the Extreme Ultraviolet Explorer Right Angle Program",
to appear in Astronomical Journal
---------------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme
Ultraviolet Astrophysics, University of California, Berkeley, CA 94720,
USA. The opinions expressed are those of the authors. EUVE Principal
Investigators and Newsletter Publishers: Dr. R.F. Malina and Professor
C.S. Bowyer. EGO and Archive Science Manger: C.A. Christian. Archive
Manager and Newsletter Editor: B.A. Stroozas. Funded by NASA contracts
NAS5-30180 and NAS5-29298. Send newsletter correspondence to:
ceanews@cea.berkeley.edu. The EUVE project is managed by NASA's GSFC.
The GSFC Project Manager: Paul Pashby, Project Scientist: Dr. Yoji
Kondo, Deputy Project Scientist: Dr. Ronald Oliversen. NASA HQ Program
Scientist: Dr. Robert Stachnik, Program Manager: Dr. G. Riegler. GSFC
Project Operations Director: Mr. Kevin Hartnett. Information on the
EUVE Guest Observer Program is available from: Dr. Y. Kondo, Mail Code
684, GSFC, Greenbelt, MD 20771 at (301) 286-6247 or e-mail to
euve@stars.span.nasa.gov.
END-----------EUVE------------ELECTRONIC---------------NEWS-------------END
|
| 770.48 | EUVE Newsletter Vol 4, No. 11 | NETCAD::BATTERSBY | | Thu Nov 17 1994 12:04 | 547 |
| Article: 6706
From: ceanews@sunset.cea.berkeley.edu (EUVE Electronic Newsletter distribution)
Newsgroups: sci.astro,sci.space.tech,sci.space.science,sci.space.news
Subject: EUVE Electronic Newsletter
Date: 16 Nov 1994 17:59:51 GMT
Organization: Center For Extreme Ultraviolet Astrophysics
EEEEEEEEEEE U U V V EEEEEEEEEEE
E U U V V E
E U U V V E
EEEEEEE U U V V EEEEEEE
E U U V V E
E U U V V E
EEEEEEEEEEE UUUUU V EEEEEEEEEEE
---------------------------------------------------------------------------
ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
---------------------------------------------------------------------------
Vol 4, No. 11 16 Nov 1994 ISSN 1065-3597
---------------------------------------------------------------------------
Notes from the Editor
=====================
by Brett A. Stroozas, EUVE Data Archive and Science Support (DASS) Manager
Welcome to the electronic newsletter for NASA's Extreme Ultraviolet Explorer
(EUVE) satellite, which is compiled and published monthly by the EUVE Science
Archive group at the Center for EUV Astrophysics (CEA) at the University of
California, Berkeley, CA. The contents of this issue of the newsletter are as
follows:
1. Recent EUVE Science Highlights
2. Update on EUVE Test-Bed Activities
3. Notes from the EUVE Guest Observer Center
3.1 EUVE Cycle III NRA
3.2 EUVE GO Program at the Senior Science Review
4. Notes from the EUVE Science Archive
4.1 GO Data Release List for 1 December 1994
4.2 EUVE Science Archive Guest Investigator (GI) Program
4.3 New Services Available via the World Wide Web
4.4 Accessing the Archive
5. Abstracts of Recently *Accepted* EUVE Papers
The EUVE observatory performed well throughout the month of October,
completing observations of the following Guest Observer (GO) targets (alternate
name and spectral type information taken from the SIMBAD or internal CEA
databases):
-----------------------------------------------------------------
Target Alternate Spectral Observation
Name Name Type GMT Date(s) Notes
-----------------------------------------------------------------
beta Cet HD 4128 K0III 30 Sep - 06 Oct 1994 --
VY Ari HD 17433 K0 06 Oct - 12 Oct 1994 --
SURVEY -------- ---- 12 Oct - 13 Oct 1994 E1
Moon -------- SS 13 Oct - 13 Oct 1994 --
kappa Cet HD 20630 G5Vvar 13 Oct - 18 Oct 1994 --
epsilon CMa HD 52089 B2Iab 18 Oct - 19 Oct 1994 E2
Moon -------- SS 19 Oct - 19 Oct 1994 --
UX Ari HD 21242 G5IV 19 Oct - 22 Oct 1994 --
PSR J0437-4713 -------- Pulsar 23 Oct - 12 Nov 1994 --
-----------------------------------------------------------------
E1: Engineering test to aid in determining the proper ground
software conversion factor for the high voltage power supply
on the long-wavelength spectrometer.
E2: Engineering test to aid in determining the gain degradation
at the boresight of of the deep survey imaging detector.
-----------------------------------------------------------------
To comment on or make suggestions for the EUVE electronic newsletter, please
send e-mail to ceanews@cea.berkeley.edu (Internet).
1. Recent EUVE Science Highlights
=================================
by Dr. Antonella Fruscione, EUVE Scientist
The following are recent science highlights from the EUVE mission:
o The paper "A Volume-Limited Survey of High Galactic Planetary Nebulae with
EUVE" (Fruscione, A. et al. 1994; CEA publication #609) will appear in the
February issue of the Astrophysical Journal. It reports the detection of
seven Planetary Nebulae (PN) during the EUVE all-sky survey, two of which
are newly discovered EUV sources. The emission from the objects is
consistent in all cases with that of a point source and therefore is most
probably originating from the PN central stars. From the observed values
of the EUV count rates and from assumption about the absorption occurring
in the interstellar medium between the Earth and the stars, the authors
derive temperatures of about 100,000 degrees for the emitting stars.
o The prototype eclipsing binary Algol was observed by the EUVE spectrometers
over nearly 1.5 orbital periods. Dr. R. Stern and collaborators, in an
abstract submitted for the 1995 meeting of the American Astronomical Society,
report that emission lines from high ionization states of iron, formed at
high temperature (up to 20 million degrees), are clearly detected in the
overall spectrum and that a quiescent continuum is present which increases
towards shorter wavelengths. Using synthesized spectra of optically thin
line and continuum emission, Dr. Stern and collaborators find that the iron
in the corona of Algol is under-abundant by factors of ~2-4 relative to the
Sun, unless an unreasonably large quantity of coronal plasma at temperatures
greater than 30 million degrees is present in the quiescent spectrum. The
latter possibility is, however, inconsistent with available X-ray data.
o Dr. M. Mathioudakis and collaborators (in a paper recently submitted to
Astronomy and Astrophysics) reports the detection of 23 new main-sequence
stars observed with EUVE during the all-sky survey, increasing the total
number of main-sequence stars detected in the EUV by ~12%. The authors
used the EUVE data to computed EUV fluxes (a measure of the star's activity)
for a total of 74 main-sequence stars with known rotational period to study
the connection between activity and rotation. They find that, as seen in
the EUV, saturation (the maximum level of activity in a star) in
chromospheric fluxes occurs in lower rotational velocities than it does in
coronal fluxes. One of the detected stars is the low activity M dwarf star
Gl 685. The EUVE observation indicates that this star has a cool corona at
less than about 2.5 million degrees and that the most significant amount of
radiative losses in the corona of this dwarf star emerges in the EUV.
2. Update on EUVE Test-Bed Activities
====================================
by Tom Morgan, EUVE Test-Bed Manager
The EUVE test-bed continues operations with the Low Earth Orbit Demonstrator
(LEO-D) at the Jet Propulsion Laboratory (JPL). This test-bed is attempting
to use a fully automated system of low-cost weather satellite ground stations
for the transmission of data from low-earth orbit astronomy satellites.
Pointed and non-pointed tests in both the GN (ground network) and spread
spectrum (NASA Tracking and Data Relay Satellite System-compatible) modes will
continue through November. Preliminary results indicate good potential for
success in pointed spread spectrum mode. Drs. Karen and Richard Hackney from
the NASA Kentucky Space Grant Consortium recently visited CEA to investigate
EUVE progress on the LEO-D project.
Evaluation continues with the JPL Space Craft Health Inference Engine (SHIE).
This is an augmented intelligence (AI) rule-based software application which
performs actions based in response to how the rules apply to the incoming data
stream. Initial testing indicates the inferencing speed of the application
would make it a valuable tool in systems having a requirement for elevated
processing speeds.
Evaluation continues of the JPL Selective Monitor (SelMon). Unlike other
traditional systems, this AI software application improves upon existing
monitoring systems by employing several techniques for recognizing abnormal
behavior and, when noted, focusses attention on the anomaly to provide critical
information in the early stages of a potential emergency. Initial "ground
truths" testing indicate SelMon responds correctly 100% of the time to known
anomalies. Testing continues to assess the SelMon capabilities to detect
anomalies previously undetected by EUVE software, but later detected by manual
engineering analysis.
3. Notes from the EUVE Guest Observer (EGO) Center
==================================================
by Anne Miller, EGO Technical Writer
3.1 EUVE Cycle III NRA
----------------------
The EUVE Project office at Goddard Space Flight Center (GSFC) received 106
proposals in response to NASA Research Announcement (NRA) 94-OSS-13. This NRA
allows researchers to propose for large programs of research using all four
EUVE telescopes -- the three imaging "scanners" and the Deep Survey/Spectrometer
(DS/S). This is the first opportunity for researchers to propose for pointed
scanner observations, which are carried out via the Right Angle Program (RAP;
so named because the scanners are mounted at right angles to the DS/S).
Technical and scientific reviews of the Cycle III proposals are underway and
the final Peer Review and Selection of targets is scheduled for 8-9 December.
3.2 EUVE GO Program at the Senior Science Review
------------------------------------------------
The EUVE Users Group presented an exciting plan for the science to be done
with EUVE in case of an extended mission. The presentation, made by Dr. Harry
Shipman (Chair of the Users Group) and supported by Dr. Andrea Dupree, was
delivered to the NASA Astrophysics Division Senior Review Panel. The current
EUVE mission is scheduled to end in February 1996; an extended mission would
continue for a few additional years.
4. Notes from the EUVE Science Archive
======================================
by Brett Stroozas, DASS Manager
4.1 GO Data Release List for 1 December 1994
--------------------------------------------
The table below lists the GO observations which become public on 1 December
1994; all have been reprocessed with the most recent versions of the EGO Center
software and reference data. For each entry is given the target name, the
approximate exposure time in kiloseconds, the GMT start and end date(s) for
the observation, the spectral type of the target, and the data identification
code. All public data sets may be ordered from the archive via the World Wide
Web (WWW) and electronic or postal mail (see addresses below). Please be sure
to include in your order the DataID(s) of interest.
The data rights policy for GO observations states that GO's have proprietary
rights to the data for one year from the date (s)he receives it. It is often
the case that long observations are broken up over many months; e.g., an
observation approved for 60 ksec may actually be observed for 10 ksec one
month, 20 ksec the next and 30 ksec three months later. In such cases the
one-year proprietary period begins after the GO receives the final piece of
the complete observation.
===============================================================
Target ~Exp Observation Date(s) SpT DataID
Name (ksec) Start End
===============================================================
Data Sets Available 1 Dec 1994:
71_TAU 108 Oct 24 1993 - Oct 28 1993 F0V go0116
AB_DOR 195 Nov 4 1993 - Nov 11 1993 K1 go0117
ALGOL 130 Oct 30 1993 - Nov 4 1993 B8V go0118
EPSILON_ERI 60 Oct 22 1993 - Oct 24 1993 K2V go0119
MOON 2 Aug 28 1993 - Aug 28 1993 SS go0120
MOON 2 Sep 1 1993 - Sep 1 1993 SS go0121
MOON 2 Sep 28 1993 - Sep 28 1993 SS go0122
MOON 1 Oct 4 1993 - Oct 4 1993 SS go0123
MOON 2 Oct 27 1993 - Oct 27 1993 SS go0124
MOON 2 Oct 29 1993 - Oct 29 1993 SS go0125
MOON 2 Nov 3 1993 - Nov 3 1993 SS go0126
MOON 3 Nov 29 1993 - Nov 29 1993 SS go0127
PSR1929+10 39 Oct 10 1993 - Oct 12 1993 Pulsar go0128
RE0503-285 52 Oct 20 1993 - Oct 22 1993 WD go0129
WD0004+330 44 Oct 19 1993 - Oct 20 1993 WD go0130
===============================================================
4.2 EUVE Science Archive Guest Investigator (GI) Program
--------------------------------------------------------
In order to promote research using EUVE data, CEA is pleased to announce the
EUVE Guest Investigator (GI) Science Program. The purpose of the GI Program as
an educational service which provides to researchers education and training in
the use of public EUVE data. (The basic EUVE data sets are skymaps and
"pigeonholes" -- photon event lists -- from the the all-sky and deep surveys
and multi-channel spectra from the Guest Observer Program.) In effect, the
GI Program offers CEA's technical experience and intricate knowledge of the
EUVE instrumentation and data to the external research community.
As GIs, researchers will receive from CEA a standard package of support to
assist them with their data analysis. This standard package includes up to
one week (five working days) of free access -- either as a local visitor or
remotely -- to various CEA resources including computer processing power, up
to 500 megabytes of disk space, and access to one technical research assistant
who will assist the researcher in understanding and using the EUVE data. At
the end of the five days, GIs should be fully able to analyze EUVE data
themselves at their home institutions.
Researchers interested in analyzing EUVE data are encouraged to apply for
the GI program. Since CEA resources are limited, a maximum of three GIs will
be actively supported at any one time. For more information on how to become
a GI, contact the EUVE Science Archive via telephone at (510) 642-3032 or by
e-mail at archive@cea.berkeley.edu.
The timing of the implementation of the EUVE GI Program coincides well
with the last month's NRA (94-OSS-17) from the NASA Astrophysics Data Program
(ADP) which includes EUVE data in its call for proposals. More information
on the ADP and the proposal process is available via anonymous ftp at
ftp.astrophysics.hq.nasa.gov in the directory /pub/NRAs/ADP/94-OSS-17. All
proposals are due by 25 January 1995.
4.3 New Services Available via the World Wide Web (WWW)
-------------------------------------------------------
The "Monsignori-Fossi and Landini Plasma Emission Model in the EUV Range"
is now available in the "Software and Services" section of the Archive on
the CEA WWW site (http://www.cea.berkeley.edu). This tool calculates the
spectrum of an optically thin plasma in the EUVE spectral range (60-760 A) for
a user-specified logarithmic plasma temperature, electron density, logarithmic
emission measure (EM), distance, and intervening interstellar medium (ISM)
hydrogen and helium column densities.
The spectrum is derived using emissivity tables from the X-ray/EUV spectral
code by Landini and Monsignori-Fossi (1990), recently revised using more
accurate atomic data computations (Monsignori-Fossi & Landini, 1994). Spectra
may be calculated for isothermal models in the temperature range log(T) =
4.5-8.0. The ISM attenuation is performed by the same routines used by the
ISM tool (Rumph, Bowyer, & Vennes 1994), also available in this archive.
The resolution of the output spectrum is currently fixed at 0.5 A across the
whole wavelength range. This value was chosen because it corresponds to the
maximum resolution of the EUVE spectrometers. The output spectrum may be in
either photon or energy units. The user has the option of having the output
spectrum as well as the emissivity tables corresponding to the chosen input
temperature sent to them by e-mail.
4.4 Accessing the Archive
-------------------------
Listed below are the various methods for accessing EUVE archival material:
o CEA World Wide Web URL:
http://www.cea.berkeley.edu (Mosaic/lynx remotely)
telnet www.cea.berkeley.edu 200 (lynx locally at CEA)
o NASA's Astrophysics Data System:
http://adswww.colorado.edu/adswww/adshomepg.html (Mosaic/lynx)
o CD-ROM Series: Volumes 1.1, 2.1, and 2.2 (seven separate CDs) available
o e-mail: archive@cea.berkeley.edu
o anonymous FTP (or gopher): ftp.cea.berkeley.edu
o EUVE Electronic Newsletters:
Subscriptions: majordomo@cea.berkeley.edu ("subscribe euvenews")
Post message to all subscribers: euvenews@cea.berkeley.edu
o Postal Mail:
The EUVE Public Science Archive
Center for EUV Astrophysics
2150 Kittredge St.
Berkeley, CA 94720
510-642-3032 (voice) or 510-643-5660 (fax)
archive@cea.berkeley.edu
5. Abstracts of Recently *Accepted* EUVE Papers
===============================================
Included below are abstracts of EUVE-related papers recently *accepted*
for publication. For those papers authored by CEA scientists, the EUVE
publication numbers are indicated. Unless otherwise noted, researchers may
obtain preprints of CEA papers by sending an e-mail request containing the
publication number(s) of interest to pub@cea.berkeley.edu.
Researchers are encouraged to contribute *accepted* EUVE-related abstracts
for inclusion in future editions of this newsletter; abstracts or full papers
will also be posted under the CEA WWW Home Page. Please send all abstracts
or papers to archive@cea.berkeley.edu.
--------------------------------------------------------------
IRON IN THE EUVE SPECTRUM OF PG1234+482
S. Jordan and D. Koester
Astronomische Gesellschaft, Abstract Series No. 10, p. 60, 1994.
White dwarfs of spectral type DA are defined as showing only Balmer lines
of hydrogen in the optical part of the spectrum. However, the optical part
of the spectrum is quite insensitive to small traces of helium or heavier
elements so that the evidence for additional absorbers in hot DAs rests
entirely on observations in the soft X-ray, EUV and UV. The flux in the
soft X-ray region has the strongest dependence on small traces of absorbers
heavier than hydrogen. For some hot white dwarfs with T_eff >= 38,000 K
measurements with the EINSTEIN, EXOSAT, and ROSAT satellites clearly
indicated the presence of absorbing material at wavelengths below about
300 A. Unfortunately, the limited energy resolution of these detectors
did not allow a unique determination of the chemical composition. Therefore
the analysis of the X-ray data was mostly restricted to hydrogen atmospheres
with small traces of helium. Direct evidence for such absorbers was the
detection of ions of heavier elements NV, SiIV, CIV, and FeV in IUE high
resolution spectra of G191-B2B. PG1234+482, after being classified as a
sdB was found to be a hot DA by our group. From the optical spectrum we
determined an effective temperature of 50,000 +/- 3,000 K, which is compatible
with the IUE low resolution spectrum. ROSAT pointed observation could not
be reproduced by assuming model atmospheres containing only hydrogen and
helium. With the limited energy resolution of ROSAT it was, however, not
possible to determine the metal abundance unambiguously. With its much
higher spectral resolution the EUVE satellite is able to detect spectral
lines in the extreme UV. Significant flux could be detected with the short
and medium wavelength spectrograph between about 75 and 300 A. We compared
the measurement in the short wavelength to a synthetic spectrum containing
only small traces of the iron group elements in an otherwise pure hydrogen
atmosphere. Perfect agreement between theory and observation cannot be
expected due to fixed pattern noise in the observation and due to uncertainties
of the iron opacities. However, the energy distribution and several strong
absorption features can be reproduced by the model. By varying the parameters
we conclude that the iron abundance is about 1.5-3.0E-7, lower than predicted
by Chayer et al. (1994, preprint) by detailed calculations of the radiative
forces in hot DA white dwarf atmospheres. A more complete paper by Jordan
S., Koester D., Finley D., Werner K. is in preparation.
--------------------------------------------------------------
EUVE OBSERVATIONS OF NGC 5548
J.S. Kaastra, R. Mewe, J. Heise, F.J.M. Alkemade, C.J. Schrijver, and T. Carone
IAU Symposium No. 159, Active Galactic Nuclei Across the Electromagnetic
Spectrum, Geneva, 30 Aug - 3 Sep 1993.
The first extreme ultraviolet spectrum of NGC 5548 obtained by EUVE is
presented.
--------------------------------------------------------------
ON THE PREDICTED ABUNDANCES OF IRON AND NICKEL SUPPORTED BY RADIATIVE
LEVITATION OF HOT DA WHITE DWARFS
P. Chayer, F. LeBlanc, G. Fontaine, F. Wesemael, G. Michaud, and S. Vennes
To appear in Astrophysical Journal Letters [CEA Publication #613]
We present the results of detailed radiative forces calculations for iron
and nickel levitating in hot DA white dwarf atmospheres. This follows from
the determination of the iron abundance in a handful of hot DA stars by a
number of authors and, more particularly, from the recent identification and
abundance analysis of nickel carried out by Werner & Dreizler for these same
stars. Our calculations are based on the extensive atomic data set compiled
by Kurucz for the iron group elements. We show that radiative levitation is
more than sufficient to account for the abundances of iron and nickel observed
in hot DA white dwarfs. However, we also find that the observations exhibit
an abundance pattern which cannot be explained in detail by the predictions
of radiative levitation theory. This finding adds to mounting evidence that
other mechanisms must be at work in the atmospheres of these objects and
compete with radiative levitation and gravitational settling.
--------------------------------------------------------------
LOW-COST OPERATIONS APPROACHES AND INNOVATIVE TECHNOLOGY TEST-BEDDING AT THE
EUVE SCIENCE OPERATIONS CENTER
R.F. Malina
Presented at the 45th International Astronautical Congress, IAA Symposium on
Small Satellite Missions, Session on "Low Cost Approaches for Small Satellite
Mission Operations and Data Analysis," Jerusalem, Israel, 9-14 Oct 1994.
[CEA Publication #614; not preprinted]
The NASA Astrophysics Program faces harsh realities in the new NASA budget
environment. Even though there is an increasing number of successfully operating
NASA astrophysics satellites, the Astrophysics Division mission operations and
data analysis budget will be decreasing annually over the next few years. As
a result the NASA Astrophysics Division must either terminate operation of
successful and highly productive observatories or develop techniques for
operating satellites at radically lower costs. The NASA Extreme Ultraviolet
Explorer (EUVE) astronomy satellite, which is presently operating flawlessly
and returning a stream of scientific breakthroughs in the new field of EUV
astronomy, is currently slated to be turned off in 1996. The EUVE project has
adopted an aggressive plan to find ways of operating EUVE at lower cost. The
EUVE project at the University of California, Berkeley (UCB; which has
responsibility for EUVE science operations), and Dr. Ronald Polidan of GSFC
have laid out a new mission operations concept for EUVE that will allow EUVE's
operating costs to be lowered. It will also provide a management experiment
and technology test-bed to allow NASA to transfer lessons learned and new tested
approaches gained from EUVE to other missions. The EUVE Science Operations
Center (ESOC) at UCB, has adopted these approaches and is using new operations
software that allows semi-autonomous operations to be implemented. Under this
plan the ESOC is making a transition from a three-shift, around-the-clock
operation to a one-shift, human-tended operation with use of the RTworks
artificial intelligence (AI) software package for autonomous operations during
the untended shifts. The conversion to one-shift operations was carried out
during 1994 and has been accomplished in less than nine months. An autonomous
paging system automatically makes telephone contact with remote duty engineers
upon detection of anomalies in the telemetry stream so that response to
detected anomalies can be carried out. Additional areas of cost reduction
include that of the observatory science planning and scheduling and autonomous
monitoring and error correction in the communications and ground computer
systems. The on-board robustness of the EUVE spacecraft, a Fairchild MMS
platform, allows acceptable risk tradeoffs between on-board and ground
functions for assuring ultimate health and safety of the spacecraft and payload
system. EUVE has been selected by NASA Code X for test-bedding of innovative
software techniques for cost reduction in the operations of scientific
satellites; EUVE is currently collaborating with researchers at NASA Ames
Research Center (ARC), the Jet Propulsion Laboratory (JPL), and the Goddard
Space Flight Center (GSFC). Other areas of cost reduction include test-bedding
of direct-to-ground communications with autonomous ground stations (EUVE
currently uses the Telemetry and Data Relay Satellite System (TDRSS) for all
communications), using the on-board global positioning system (GPS) for all
orbit determination needs, and streamlining of data delivery to scientific
users via the EUVE electronic archive and provisions for remote computing
facilities. An additional critical element of the EUVE low-cost innovations
is the direct involvement of University of California undergraduate students
in all aspects of operations. The EUVE educational outreach program also uses
the ESOC as a laboratory for K-12 teacher training workshops. In this paper
we describe elements of cost reduction innovation and technology test-bedding
on EUVE as well as some lessons learned. One of the lessons we have learned
from migrating the EUVE ESOC from three to one shift is that today's AI
software allows the design and operation of a fully autonomous EUVE Science
Operations Center. We are now developing plans to migrate from one shift to
zero shifts. We believe that this will result in a more robust and lower risk
science operations concept than the original three-shift, around-the-clock
operations. Although we are suspicious of slogans, we believe that this will
be an excellent example of "less is more."
--------------------------------------------------------------
EDUCATIONAL OUTREACH ON NASA'S EXTREME ULTRAVIOLET EXPLORER SATELLITE PROGRAM
R.F. Malina, I. Hawkins, and C. Christian
Presented at the 45th International Astronautical Congress, Symposium on Space
and Education, session on "Education Structures," Jerusalem, Israel, 9-14
Oct 1994. [CEA Publication #616; not preprinted]
NASA's Extreme Ultraviolet Explorer (EUVE) satellite was launched in June
of 1992. As an intrinsic part of the operations phase of this satellite, an
education outreach program has been developed for undergraduate students, K-12
students and educators, and for the general public. These projects have been
funded by NASA's Astrophysics Division Grant Supplements for Education Program
and by the EUVE project. We review the underlying ideas that motivate our
approach in using EUVE as a tool for educational outreach. In particular we
note the need for collaborations between the research project and informal
science museums and centers who are best placed to establish long term programs
with schools and the K-12 educational community. The EUVE project has also
made a commitment to staff involvement in educational outreach, rather than
setting up a separate educational outreach activity. Finally, we emphasize
the need to carry out educational outreach for space science in an
interdisciplinary context that ties space science to other disciplines as well
as to culture at large. We describe a new program, The Science Information
Infrastructure (SII), that seeks to establish collaborations between the EUVE
project, the Harvard Smithsonian Astrophysical Observatory, and science museums
including the San Francisco Exploratorium, The Lawrence Hall of Science, The
Adler Planetarium in Chicago, the UC Museum of Paleontology, the Smithsonian
Air and Space Museum, the New York Hall of Science, and the Science Museum of
Virginia. Teachers at each of these museums will participate in workshops to
develop lesson plans and educational materials that will be disseminated
through World Wide Web sites at each of the participating institutions. A
pilot project, Science On Line, is under way involving a subset of the SII to
develop initial materials in early 1995.
--------------------------------------------------------------
THE EUVE BIBLIOGRAPHY AS OF OCTOBER 1994.
Center for EUV Astrophysics [CEA Publication #617]
NASA's Extreme Ultraviolet Explorer (EUVE) launched in June 1992. This
bibliography lists all EUVE-related publications to date. The numbers
preceding most titles are the report numbers by which the papers may be
requested from the Center for EUV Astrophysics (CEA), UC Berkeley. Papers
without numbers are by non-CEA guest observers or members of the astrophysics
community. Asterisks indicate papers using EUVE data. Papers are listed
by subject and in reverse chronological order.
--------------------------------------------------------------
EXTREME ULTRAVIOLET LIGHT CURVES OF UZ FOR: EVIDENCE FOR ACCRETION STREAM
ABSORPTION AND VERTICAL EXTENT OF THE ACCRETION SPOT
John K. Warren, Martin M. Sirk, and John V. Vallerga
To appear in Astrophysical Journal [CEA publication #620]
We report on two pointed observations of UZ For carried out by the imaging
photometers aboard the Extreme Ultraviolet Explorer (EUVE), one as part of
the EUVE Right Angle Program and one as an off-axis source during a guest
observation. Both observations lasted approximately three days and covered
a total of 72 orbits of the UZ For binary providing multiple coverage of all
the orbital phases of UZ For. The resulting high signal-to-noise, phase-folded
light curve strongly constrains the emission and absorption geometry of UZ For.
We have detected a narrow absorption dip that we attribute to the accretion
stream at the location of the stagnation region many white dwarf radii away
from the accretion spot and have also detected a broad dip caused by absorption
much closer to the white dwarf surface. Both absorption effects are variable
in time and phase. Based on the time scales of M-star eclipse ingress and
egress, the angular spot size is constrained to be < 5 deg; thus the ratio
of spot area to white dwarf surface area is <= 0.0005. To explain the light
curve phase duration given this small angular spot size, the extreme
ultraviolet (EUV) accretion spot must be raised vertically by approximately
5% of the white dwarf radius.
--------------------------------------------------------------
REFERENCES
==========
o Landini, M., and Monsignori-Fossi, B.C., 1990, Astronomy & Astrophysics,
82, 229
o Monsignori-Fossi, B.C., and Landini, M., 1994, Solar Physics, 152, 81
o Rumph, T., Bowyer, S., and Vennes, S., 1994, Astronomical Journal,
107(6), 2108
---------------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme
Ultraviolet Astrophysics, University of California, Berkeley, CA 94720,
USA. The opinions expressed are those of the authors. EUVE Principal
Investigators and Newsletter Publishers: Dr. R.F. Malina and Professor
C.S. Bowyer. EGO and Archive Science Manger: C.A. Christian. Archive
Manager and Newsletter Editor: B.A. Stroozas. Funded by NASA contracts
NAS5-30180 and NAS5-29298. Send newsletter correspondence to:
ceanews@cea.berkeley.edu. The EUVE project is managed by NASA's GSFC.
The GSFC Project Manager: Paul Pashby, Project Scientist: Dr. Yoji
Kondo, Deputy Project Scientist: Dr. Ronald Oliversen. NASA HQ Program
Scientist: Dr. Robert Stachnik, Program Manager: Dr. G. Riegler. GSFC
Project Operations Director: Mr. Kevin Hartnett. Information on the
EUVE Guest Observer Program is available from: Dr. Y. Kondo, Mail Code
684, GSFC, Greenbelt, MD 20771 at (301) 286-6247 or e-mail to
euve@stars.span.nasa.gov.
END-----------EUVE------------ELECTRONIC---------------NEWS-------------END
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