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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
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Vol 5, No. 1 20 Jan 1995 ISSN 1065-3597
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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, compiled and published monthly by the EUVE Science Archive
group at the Center for EUV Astrophysics (CEA) in Berkeley, CA. The contents
of this issue of the EUVE electronic newsletter are as follows:
1. Approved Cycle 3 GO Programs
2. Failure of On-Board Tape Recorder Unit
3. Notes from the EUVE Science Archive
3.1 EUVE Public RAP
3.2 GI Program Information on WWW
3.3 On-Line Access to EUVE
4. 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).
The EUVE observatory performed well throughout the month of December 1994,
performing 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
-----------------------------------------------------------------
V471 Tau WD 0347+171 WD 28 Nov - 02 Dec 1994 --
HD 17925 SAO 148647 K1V 02 Dec - 08 Dec 1994 --
PSR J0108-1431 ------ Pulsar 08 Dec - 11 Dec 1994 --
Moon ------ SolSys 11 Dec - 12 Dec 1994 --
GD 50 WD 0346-011 WD 12 Dec - 14 Dec 1994 --
EK UMa RE J1051+540 CV 14 Dec - 15 Dec 1994 --
CN Leo RE J1056+070 M6V 15 Dec - 19 Dec 1994 ^TOO
PSR J0108-1431 ------ Pulsar 19 Dec - 21 Dec 1994 --
YZ CMi RE J0744+033 M4.5V 21 Dec - 24 Dec 1994 --
PSR J0108-1431 ------ Pulsar 24 Dec - 26 Dec 1994 --
RE 1149+284 ------ CV 26 Dec - 12 Jan 1995 --
-----------------------------------------------------------------
Key: ^TOO = Target of Opportunity
1. Approved Cycle 3 GO Programs
===============================
by Dr. Ron Oliversen, EUVE Associate Project Scientist at GSFC
The EUVE peer review for Cycle 3 GO proposals was held 8-9 December 1994.
The recommendations of the peer review committee have been reviewed by NASA and
the approved programs are listed below. For each approved proposal the list
includes the Proposal Identification Number, the Principal Investigator (PI),
the PI's Institution, and the Proposal Title. The list of selected targets for
each program will soon be available in the EGO Center section of the CEA World
Wide Web (WWW) site. If you have any questions about these results please
contact Ron Oliversen by telephone (301-286-6290) or Internet e-mail
(stars@oliversen.gsfc.nasa.gov).
APPROVED EUVE CYCLE 3 GUEST OBSERVER PROGRAMS
SPECTROMETER/DEEP SURVEY
------------------------
002 Mauche LLNL
VW Hydri in Outburst and Quiescence
003 Shemi Tel Aviv University
The Nature of the Unidentified EUV Sources: Accreting Isolated
Neutron Stars?
004 Cassinelli University of Wisconsin, Madison
An EUVE Study of the B-stars epsilon and beta CMa
007 Heber Universitaet Erlangen-Nuernberg
Iron Abundance in Hot Hydrogen-Rich Central Stars of Planetary Nebulae
008 Lieu University of California, Berkeley
Observation of a Shadow in the Diffuse EUV Background Cast by an IRAS
Cirrus Cloud
011 Rucinski Eureka Scientific, Inc.
Saturated Activity: Very Close, Detached Binary Stars
013 Shipman University of Delaware
Probing the Mystery of the Unidentified EUVE Sources
014 Szkody University of Washington
A Study of Magnetic Accretion in VV Pup and BL Hyi
017 Mumma NASA/GSFC
EUVE Search for Neon and Helium in Comet d'Arrest and in a Dynamically
New Comet
020 Lallement Service d'Aeronomie du CNRS
Local Interstellar Cloud Ionization and Size of the Heliosphere
024 Cheng Catholic University
EUVE and Multifrequency Observations of 3C 273
026 Leahy University of Calgary
Observation of Her X-1 During The Short-On Phase
027 Ayres University of Colorado
Gappers & Clumpers, cont'd
029 Mullan University of Delaware
Test of an Acoustic Mechanism for Atmospheric Heating in
Dynamo-Deficient F Stars
033 Mauche LLNL
Simultaneous Multiwavelength Observations of Dwarf Novae in Outburst
035 Vennes University of California, Berkeley
Accretion and Diffusion in the Atmosphere of the White Dwarf in
the Binary System EUVE 0720-317 and Siblings
036 Barstow University of Leicester
A High Signal-to-Noise Study of the Role of Helium in DA White Dwarfs
038 Barstow University of Leicester
A High Signal-to-Noise Study of the Composition and Structure of the
DAO White Dwarf in RE 0720-318
042 Waldron Applied Research Corporation
A Study of EUV Line Emission from the O4f Star zeta Puppis
043 Schmitt MPE
An EUV Study of the Eclipsing M-Dwarf Binary System YY Geminorum
045 Hall Johns Hopkins University
EUVE Observations of the Jupiter System
046 Rosen University of Leicester
The Soft Spectral Component in the Exceptional Intermediate Polar
Binary, RE J0751+14
047 Ambruster Villanova University
Initial Conditions on the Zero Age Main Sequence (ZAMS): Coronal
Structure as a Function of Rotation
053 Simon University of Hawaii
Coordinated Observations of AD Leo: Testing the Flare Model
054 Warren Eureka Scientific, Inc.
Studies of the EUV Excess in AM Herculis Stars
055 Judge HAO/NCAR
Solar Variability, Lunar Spectroscopy, and Earth's Upper Atmosphere
058 Konigl University of Chicago
EUV Spectroscopy of Mrk 421
061 Howell Planetary Science Institute
EUV Polarization Observations of RE 1307+535
062 Mauche LLNL
EUVE Spectroscopy of the Accretion Region in AM Herculis
063 Giampapa KPNO/NOAO
The Coronae of Low Mass Dwarf Stars
064 Brown University of Colorado
Time-Resolved Spectroscopy of RS CVn Binaries and dMe Flare Stars
067 Stern Lockheed PARL
Algol Revisited: EUVE Studies of Eclipses, Thermal Structure,
and Abundances
068 Stern Lockheed PARL
Understanding the Coronae of the X-ray Bright Hyades Giants
069 Guinan Villanova University
Evolution of the Coronal Structure of the Sun in Time
070 Guinan Villanova University
The Case of 47 Cas: A Young F0 Star With Intense Chromospheric
and Coronal Emission
072 Polidan NASA/GSFC
Hidden Companions to Early Type Stars
074 Marshall Eureka Scientific, Inc.
Spectral Variability of the EUV Excesses of 1H 0419-577 and Mk 478
076 Peters USC
A Study of EUV Emission in Active Be Stars in the Canis Major
Interstellar Tunnel
080 White University of Maryland
The Coronae of dM Stars
082 Linsky University of Colorado/JILA
Coronal Temperature Distributions and Convection-Zone Depth: The F-
and G-Type Dwarfs
083 Bruhweiler Catholic University
Multifrequency Observations of the BL Lacertae Object Mkn 421
084 Bruhweiler Catholic University
Helium and Time-Dependent Ionization in the Local ISM
087 Drake University of California, Berkeley
In Pursuit of the FIP Effect in Late-Type Stellar Coronae
088 Drake University of California, Berkeley
The Mysterious Close Binary Nucleus of the PN LoTr 5 and the Nature
of its EUV and X-ray Emission
091 Polidan NASA/GSFC
EUV Emission from the M Star in the Binary System 17 Leporis
093 Jordan Universitaet Kiel
Determining the Chemical Composition of the Hot DA White Dwarf
PG 1234+482
094 Finley Eureka Scientific, Inc.
Temperature and Gravity Dependence of Trace Element Abundances in
Hot DA White Dwarfs
095 Bloch Los Alamos National Laboratory
Location and Spectroscopy of Bright Transients of Unknown Origin
Detected by ALEXIS Using the EUVE Spectrometer and DS Instrument
097 Liebert University of Arizona
A Metal Abundance Estimate For the DAO Subdwarf Primary of BE Ursae
Majoris
098 Bookbinder Eureka Scientific, Inc.
EUVE Observations of Globular Cluster X-ray Binaries II: NGC 1851
102 Anderson University of Wisconsin
Target of Opportunity Reobservation of AG Draconis
SCANNER
-------
015 Welsh Eureka Scientific, Inc.
A Long Look Down the beta CMa Interstellar Tunnel
RIGHT ANGLE PROGRAM
-------------------
025 Howell Planetary Science Institute
Accretion Studies in AM Herculis Stars -- The RAP Version
089 Brown University of Colorado
Coronal Variability of RS CVn Binaries Due to Flaring, Rotational
Modulation, and Active Region Evolution
CYCLE 2 -- SECOND YEAR OF A 2-YEAR PROGRAM
------------------------------------------
107 Dupree Harvard CFA/SAO
EUVE Observations: Atmospheres of Cool Binaries
2. Failure of On-Board Tape Recorder Unit
=========================================
by Dennis Biroscak, Berkeley Operations Manager
EUVE was launched with two on-board tape recorders, A and B, with a total
recording capacity for 16 hours of data (8 hours per recorder). Each recorder
has two Transport Units (TU) that can each record four hours of data. To date,
EUVE has had failures in one TU on each recorder, leaving EUVE with a total
recording capacity for 8 hours of data.
The most recent failure occurred on 31 December 1994 in Tape Recorder A. An
apparent electronics failure, this problem happened while the unit was powered,
but in stand-by mode. As a result of the incident approximately four hours of
science data from the GO target RE 1149+284 remains on the recorder and is most
likely unrecoverable. Although the exact cause of the failure can't be known,
a likely candidate is a "single-event-upset" (SEU; i.e., a cosmic ray event)
which caused a short in one of the electronic control circuits.
In an unrelated incident that occurred in September 1994, EUVE had a
mechanical failure on Tape Recorder B. This incident also caused a permanent
loss of approximately four hours of data.
Although the EUVE tape recorder capacity is only half its original capacity,
there should be no trouble retrieving all science observation data. The Flight
Operations Team (FOT) at Goddard Space Flight Center (GSFC) typically dumps the
tape recorders every four to six hours, well before reaching the recorder
capacity.
The two tape recorder failures don't appear to fit a pattern of degradation
and there is no reason to believe the remaining tape units will fail soon.
However, alternate scenarios for storing science data have been considered,
including storing primarily the data from only the night-time portion of the
EUVE orbit.
3. Notes from the EUVE Science Archive
======================================
by Brett Stroozas, DASS Manager
3.1 EUVE Public RAP
-------------------
The EUVE Right Angle Program (RAP) attempts to utilize the full capacity of
EUVE by observing and analyzing data collected by the three "scanning"
telescopes during guest observer (GO) spectrometer observations. The scanners
are mounted at right angles (hence the name RAP) to the deep survey/spectrometer
telescope and provide imaging capabilities that allow for long exposure
(40-600 ksec) EUV photometry over an area of up to 19.6 square degrees in four
distinct EUV wavelength regions. Although the primary GO observations constrain
the area of sky visible to the scanners, it is often possible to position and
simultaneously observe RAP targets in the scanner fields of view during GO
observations.
In cooperation with the Archive, the EUVE Guest Observer (EGO) Center has
recently publicly released to the research community a (beta) version of the
RAP via the CEA WWW site. The Public RAP allows researchers world-wide to to
submit proposals to use the scanners during GO spectrometer observations.
Proposals are submitted electronically (via a prototype of the proposal process
to be used during the EUVE extended mission) and, once approved by the Project
Office, targets are scheduled as constraints allow into the GO science plans.
Upon the completion of a RAP observation the proposer will be notified and
arrangements made for data reduction and delivery. More detailed information
on the Public RAP is available via the EGO Center section of the CEA WWW site
or by e-mail (egoinfo@cea.berkeley.edu).
3.2 GI Program Information on WWW
---------------------------------
To promote research using EUVE data, the Archive recently announced the EUVE
Guest Investigator (GI) Science Program. The GI Program is an educational
service that provides to researchers information, services, education, and
training in the use of public EUVE data sets. Detailed information on the GI
Program -- who can and how does one become a GI, and what are the benefits of
being a GI -- is now available via the Archive section of the CEA WWW site.
3.3 On-Line Access to EUVE
--------------------------
Listed below are the various methods for on-line access to EUVE:
o World Wide Web (CEA URL):
http://www.cea.berkeley.edu/ (for those with WWW browsers)
telnet www.cea.berkeley.edu 200 (for those without WWW browsers)
o anonymous FTP/gopher: ftp.cea.berkeley.edu
o EUVE Electronic Newsletters (past issues available via CEA WWW):
Subscriptions: mail majordomo@cea.berkeley.edu ("subscribe euvenews")
Post message to all subscribers: mail euvenews@cea.berkeley.edu
o For additional information contact the Archive:
The EUVE Public Science Archive
Center for EUV Astrophysics
2150 Kittredge St.
Berkeley, CA 94720-5030
510-642-3032 (voice) or 510-643-5660 (fax)
archive@cea.berkeley.edu
4. 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 FIRST SEARCH FOR A GAMMA RAY BURST QUIESCENT COUNTERPART IN THE EXTREME
ULTRAVIOLET WITH EUVE
K. Hurley, P. Li, J. Laros, G. Fishman, C. Kouveliotou, and C. Meegan
To appear in the Astrophysical Journal.
The opening of the extreme ultraviolet window by the EUVE satellite has
provided the unique opportunity to perform the first search for a quiescent
gamma ray burst counterpart at these wavelengths. Such emission might be
expected if some bursts are related to nearby hot neutron stars or neutron
stars with accretion disks, among other objects. We report here on a 40 ksec
observation of the 1992 March 25 gamma-ray burst error box, determined by
triangulation with the Third Interplanetary Network. No quiescent 40-190 A
EUV source was identified using the Deep Survey instrument, and a 3-sigma
upper limit of 2.9E-14 ergs/cm^2/s was obtained. Similarly, upper limits
to the 140-380 and 280-760 A fluxes were obtained with the medium- and
long-wavelength spectrometers; they are 1.1E-12 and 5.0E-13 erg/cm^2/s,
respectively. We discuss the constraints which these limits impose on
thermally radiating quiescent counterparts.
--------------------------------------------------------------
CHEATING POISSON: A BIASED METHOD FOR DETECTING FAINT SOURCES IN ALL-SKY
SURVEY DATA
J. Lewis
To appear in Astronomical Society of the Pacific Conference Series
(proceedings of ADASS '94 Conference, 25-28 Sep 1994, Baltimore, MD),
1995. [CEA publication #629]
One approach to compiling a catalog of point sources from all-sky survey
data is to apply a source detection algorithm to the entire data set and
include in the catalog any location whose significance exceeds some minimum
value. The detection threshold is generally chosen to keep the expected number
of spurious detections below some more-or-less arbitrary figure; in low
signal-to-noise ratio data, such as the Extreme Ultraviolet Explorer (EUVE)
survey skymaps, even a small change in the detection threshold can result in
an explosion of spurious detections, destroying the usefulness of the catalog.
This result does not, however, imply that real sources below the limiting
catalog threshold cannot be reliably detected. If one has some prior knowledge
of where the real sources are likely to be found, it is possible to "cheat
Poisson" and include these sub-threshold sources without introducing
significant numbers of spurious detections. This paper describes the
theoretical and practical aspects of the biased search technique as applied
to EUVE all-sky survey skymaps.
--------------------------------------------------------------
INTERACTIVE FITTING OF EUVE EMISSION LINE SPECTRA
M. Abbott
To appear in Astronomical Society of the Pacific Conference Series
(proceedings of ADASS '94 Conference, 25-28 Sep 1994, Baltimore, MD),
1995. [CEA publication #630]
An interactive IRAF task for the analysis of Extreme Ultraviolet Explorer
(EUVE) emission line spectra is presented. The line flux in extracted spectra
may be measured by multiple techniques, including fitting individual lines.
Blended lines may be fit simultaneously with the EUVE spectral PSF. To aid in
identifying lines, the positions of known lines may be marked on the spectrum
during the fitting process. Also, model EUVE spectra may be constructed and
overlaid using plasma emissivities and source emission measures supplied by the
user. The task is fully compatible with the calibration data set distributed
by the EUVE Guest Observer (GO) Center and retrieves all needed instrumental
parameters from that data set. It also makes use of the newly available IRAF
support for windowing graphical user interfaces.
--------------------------------------------------------------
CENTER FOR EUV ASTROPHYSICS
S. Bowyer and R.F. Malina
To appear in the Bulletin of the American Astronomical Society (BAAS), 1994.
[CEA publication #632; not preprinted]
The Center for Extreme Ultraviolet Astrophysics (CEA) is involved in a
number of projects in extreme and far ultraviolet astronomy including EUVE,
ORFEUS, FAUST, EURD, and DUVE. In the following, we briefly describe these
projects and their current status.
--------------------------------------------------------------
SCIENTIFIC HIGHLIGHTS FROM THE EXTREME ULTRAVIOLET EXPLORER OBSERVATORY
S. Bowyer and R.F. Malina
To appear in COSPAR: Advances in Space Research (proceedings of the 30th
COSPAR Scientific Assembly, Hamburg, July 11-21, 1994). [CEA publication
#638]
We present a few scientific highlights from the Extreme Ultraviolet Explorer
(EUVE) all-sky and deep surveys, from the EUVE Right Angle Program, and from
the EUVE Guest Observer Program. The First EUVE Source Catalog includes 410
extreme ultraviolet (EUV) sources detected in the initial processing of the
EUVE all-sky data. A program of optical identification indicates that
counterparts include cool star coronae, flare stars, hot white dwarfs, central
stars of planetary nebulae, B star photospheres and winds, an X-ray binary,
extragalactic objects (active galactic nuclei, BL Lacertae), solar system
objects (Moon, Mars, Io), supernova remnants, and two novae.
--------------------------------------------------------------
---------------------------------------------------------------------------
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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