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Chandra proposals are divided into the following categories:
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SOLAR SYSTEM
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===================================================================================
Proposal Number: 01100297
Proposal Title: VENUS AND MARS: THE CLOSEST PLANETARY ANALOGUES TO COMETS
PI: KONRAD DENNERL
Subject Category: SOLAR SYSTEM
Abstract: The recent discovery of unexpectedly bright X-ray emission from comets
has led to increased interest in X-ray studies of solar system objects. It has
demonstrated that even in our immediate astronomical environment surprises may be
waiting for being discovered. With their carbon and oxygen rich atmospheres and
the absence of strong magnetic fields, Venus and Mars represent the closest
planetary analogues to comets. Soft X-ray observations provide a sensitive tool
to study such atmospheres, in particular any outgassing effects. AXAF is the
first imaging X-ray satellite which is able to observe Venus, and Mars at
opposition, when it is closest to Earth.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
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22:38:27.54 -09:27:51.30 VENUS ACIS-S LETG 6.00
22:38:44.92 -09:25:42.02 VENUS ACIS-S LETG 6.00
22:48:55.82 -08:09:31.72 VENUS ACIS-I NONE 12.30
===================================================================================
Proposal Number: 01100323
Proposal Title: AXAF LOW ENERGY SPECTROSCOPY AND PHOTOMETRIC IMAGING OF COMETARY
X-RAY EMISSION FROM COMET P/TEMPEL 2
PI: CAREY LISSE
Subject Category: SOLAR SYSTEM
Abstract: The discovery of x-ray emission from comets has produced a number of
questions about the physical mechanism producing the radiation. There are now a
variety of explanations for the emission, from thermal bremsstrahlung of
electrons off neutrals or dust, to charge exchange induced emission from solar
wind ions, to reconnection of solar magnetic field lines. In an effort to
understand this new phenomenon, we propose spectroscopic and imaging photometric
observations with the AXAF ACIS-S of periodic comet P/Tempel 2 during its close
approach to Earth in 1999. Our scientific goal is to determine the mechanism(s)
responsible for the observed x-rays by producing detailed low energy spectra,
high spatial resolution images, hardness maps of the emission.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
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04:22:16.99 +60:18:20.66 LINEAR 1999 S4 ACIS-S NONE 1.00
04:22:40.07 +60:20:17.66 LINEAR 1999 S4 ACIS-S NONE 1.00
04:23:03.23 +60:22:14.74 LINEAR 1999 S4 ACIS-S NONE 1.00
04:23:26.45 +60:24:11.92 LINEAR 1999 S4 ACIS-S NONE 1.00
04:23:49.73 +60:26:09.20 LINEAR 1999 S4 ACIS-S NONE 1.00
04:24:14.01 +60:28:11.24 LINEAR 1999 S4 ACIS-S NONE 1.00
04:24:37.42 +60:30:08.68 LINEAR 1999 S4 ACIS-S NONE 1.00
04:25:00.89 +60:32:06.22 LINEAR 1999 S4 ACIS-S NONE 1.00
04:41:04.18 +61:39:55.73 LINEAR 1999 S4 ACIS-S NONE 1.00
04:41:32.79 +61:41:33.54 LINEAR 1999 S4 ACIS-S NONE 1.00
04:42:01.54 +61:43:11.64 LINEAR 1999 S4 ACIS-S NONE 1.00
04:42:30.41 +61:44:49.85 LINEAR 1999 S4 ACIS-S NONE 1.00
04:43:00.56 +61:46:32.09 LINEAR 1999 S4 ACIS-S NONE 1.00
04:43:29.66 +61:48:10.55 LINEAR 1999 S4 ACIS-S NONE 1.00
04:43:58.90 +61:49:49.12 LINEAR 1999 S4 ACIS-S NONE 1.00
04:44:28.25 +61:51:27.79 LINEAR 1999 S4 ACIS-S NONE 1.00
12:09:51.56 +10:48:36.90 Comet c/LINEAR 1999 ACIS-S NONE 1.00
12:09:56.16 +10:45:54.54 Comet c/LINEAR 1999 ACIS-S NONE 1.00
12:10:00.95 +10:43:10.09 Comet c/LINEAR 1999 ACIS-S NONE 1.00
12:10:05.73 +10:40:31.12 Comet c/LINEAR 1999 ACIS-S NONE 1.00
12:10:10.52 +10:37:50.02 Comet c/LINEAR 1999 ACIS-S NONE 1.00
12:10:15.30 +10:35:09.31 Comet c/LINEAR 1999 ACIS-S NONE 1.00
12:10:20.07 +10:32:29.00 Comet c/LINEAR 1999 ACIS-S NONE 1.00
12:10:24.84 +10:29:49.09 Comet c/LINEAR 1999 ACIS-S NONE 1.00
12:10:29.61 +10:27:09.58 Comet c/LINEAR 1999 ACIS-S NONE 1.00
12:10:34.38 +10:24:30.49 Comet c/LINEAR 1999 ACIS-S NONE 1.00
12:10:39.15 +10:21:51.80 Comet c/LINEAR 1999 ACIS-S NONE 1.00
12:10:43.91 +10:19:13.51 Comet c/LINEAR 1999 ACIS-S NONE 1.00
12:10:48.67 +10:16:35.65 Comet c/LINEAR 1999 ACIS-S NONE 1.00
12:10:53.43 +10:13:58.15 Comet c/LINEAR 1999 ACIS-S NONE 1.00
12:10:58.20 +10:11:21.08 Comet c/LINEAR 1999 ACIS-S NONE 1.00
12:11:02.96 +10:08:44.41 Comet c/LINEAR 1999 ACIS-S NONE 1.00
===================================================================================
Proposal Number: 01100334
Proposal Title: X-RAY IMAGING OF THE INTERACTING WINDS OF PLANETARY NEBULAE
PI: JOEL KASTNER
Subject Category: SOLAR SYSTEM
Abstract: Certain planetary nebulae (PNe) are X-ray sources. Although this
emission is generally ascribed to central stars, PNe also should display hot (>
10^6 K), diffuse X-ray emission, according to the "interacting winds" model of PN
evolution. With the unprecedented combination of spatial and spectral resolution
afforded by AXAF/ACIS we will, for the first time, distinguish unambiguously
between diffuse, nebular X-ray emission and emission from the central star. We
propose to observe 4 PNe that, based on previous ROSAT and ASCA results, are
likely to display extended, high-temperature X-ray emission in ACIS images and
spectra. These data will provide constraints on PN X-ray emission models and on
the excitation of H_2 emission from PNe.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
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19:34:45.20 +30:30:59.10 BD+303639 ACIS-S NONE 20.00
21:07:01.60 +42:14:09.70 NGC 7027 ACIS-S NONE 20.00
===================================================================================
Proposal Number: 01100814
Proposal Title: ASSESSEMENT OF INTERSTELLAR DEPLETIONS THROUGH X-RAY ABSORPTION
AND SCATTERING BY DUST
PI: THEODORE SNOW
Subject Category: SOLAR SYSTEM
Abstract: We propose to obtain AXAF/LETGS spectra of K- and L-shell absorption
edges and scattering halos due to dust along the line of sight to X Persei. These
data, along with our existing HST/GHRS results on gas in the same line of sight,
will provide direct information on grain composition and sizes. The combination
of AXAF and HST data will provide new insights into depletions (independent of
any assume "cosmic" abundances), and will provide important new constraints on
models for the dust as well as the relationship between stellar and ISM
compositions. X Per is a reddened power-law source with a steep high-energy
cut-off, making it an ideal candidate (with minimal confusion due to high
spectral orders), with sufficient flux to achieve S/N of about 25 in 50 ksec.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
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03:55:23.00 +31:02:45.00 X PERSEI (HD 24534) HRC-S LETG 50.00
===================================================================================
Proposal Number: 01100890
Proposal Title: SOLVING THE PUZZLE OF COMETARY X-RAY ORIGIN: OBSERVATIONS OF
COMET 10P/TEMPEL 2
PI: W. THOMAS VESTRAND
Subject Category: SOLAR SYSTEM
Abstract: The unprecedented spectroscopic and imaging capabilities of AXAF are
well suited to solving the puzzle of cometary x-ray origin. In addition, the
heliocentric and geocentric distance of Comet 10P/Tempel 2 in August 1999 will
make it an ideal subject for x-ray study. We therefore propose a 50 ksec
observation of Tempel 2 with HRC-S/LETG that will allow us to test unambiguously
the spectral predictions of the leading models for generation of cometary x-rays.
We also request a 25 ksec imaging observation with HRC-I to determine the
morphology of the cometary emission. These observations, in conjunction with our
campaign of multiwavelength observations, will allow us to test all the proposed
models for cometary x-ray emission.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
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23:04:19.25 +09:24:12.28 LINEAR 2001 A2 HRC-S LETG 2.25
23:04:36.09 +09:21:51.23 LINEAR 2001 A2 HRC-S LETG 2.25
23:04:54.76 +09:19:15.06 LINEAR 2001 A2 HRC-S LETG 2.25
23:05:11.50 +09:16:55.06 LINEAR 2001 A2 HRC-S LETG 2.25
23:05:28.18 +09:14:35.70 LINEAR 2001 A2 HRC-S LETG 2.25
23:05:44.81 +09:12:17.03 LINEAR 2001 A2 HRC-S LETG 2.25
23:06:03.21 +09:09:43.85 LINEAR 2001 A2 HRC-S LETG 2.25
23:06:21.52 +09:07:11.75 LINEAR 2001 A2 HRC-S LETG 2.25
23:06:37.92 +09:04:55.96 LINEAR 2001 A2 HRC-S LETG 2.25
23:06:54.25 +09:02:41.35 LINEAR 2001 A2 HRC-S LETG 2.25
23:14:05.44 +08:07:32.31 LINEAR 2001 A2 HRC-I NONE 2.25
23:14:25.79 +08:04:41.19 LINEAR 2001 A2 HRC-I NONE 2.25
23:14:45.50 +08:01:54.79 LINEAR 2001 A2 HRC-I NONE 2.25
23:15:04.72 +07:59:11.92 LINEAR 2001 A2 HRC-I NONE 2.25
23:15:24.55 +07:56:23.22 LINEAR 2001 A2 HRC-I NONE 2.25
23:16:15.60 +07:49:06.60 LINEAR 2001 A2 HRC-S LETG 2.25
23:16:35.43 +07:46:16.11 LINEAR 2001 A2 HRC-S LETG 2.25
23:16:55.59 +07:43:22.36 LINEAR 2001 A2 HRC-S LETG 2.25
23:17:15.71 +07:40:28.52 LINEAR 2001 A2 HRC-S LETG 2.25
23:17:35.79 +07:37:34.58 LINEAR 2001 A2 HRC-S LETG 2.25
23:17:55.69 +07:34:41.82 LINEAR 2001 A2 HRC-S LETG 2.25
23:18:14.54 +07:31:57.83 LINEAR 2001 A2 HRC-S LETG 2.25
23:18:33.80 +07:29:10.00 LINEAR 2001 A2 HRC-S LETG 2.25
23:18:53.25 +07:26:20.22 LINEAR 2001 A2 HRC-S LETG 2.25
23:19:43.35 +07:19:01.41 LINEAR 2001 A2 HRC-I NONE 2.25
23:20:02.26 +07:16:15.30 LINEAR 2001 A2 HRC-I NONE 2.25
23:20:21.36 +07:13:27.28 LINEAR 2001 A2 HRC-I NONE 2.25
23:20:40.64 +07:10:37.35 LINEAR 2001 A2 HRC-I NONE 2.25
23:20:59.47 +07:07:51.20 LINEAR 2001 A2 HRC-I NONE 2.25
===================================================================================
Proposal Number: 01100931
Proposal Title: X-RAY AFTERGLOW MEASUREMENTS BY AXAF OF GAMMA-RAY BURSTS
LOCALIZED BY THE RXTE/ASM AND HETE SATELLITES
PI: GEORGE RICKER
Subject Category: SOLAR SYSTEM
Abstract: AXAF imaging and spectroscopic TOO observations of six (6) gamma-ray
burst afterglow sources are proposed. Initial source localizations will be
provided by the RXTE/ASM and HETE satellites, supplemented by IPN measurements.
AXAF measurements will not only provide arc-second refinements of source
localizations, but will accurately measure afterglow decay and spectra,
permitting stringent tests of a variety of shock wave geometries and sequelae.
The observing team will immediately place all AXAF positions, intensities, and
spectroscopic parameters into the public domain via the GCN. Prompt optical
(photometric and spectroscopic) and radio followup will also be provided by the
proposing team.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
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GRB/TOO #1 ACIS-I NONE 10.00
GRB/TOO #2 ACIS-I NONE 10.00
===================================================================================
Proposal Number: 01100952
Proposal Title: X-RAY POSITIONS AND AFTERGLOWS OF GAMMA-RAY BURSTS
PI: LUIGI PIRO
Subject Category: SOLAR SYSTEM
Abstract: BeppoSAX recently discovered X-ray transients associated with gamma-ray
bursts (GRBs), leading to reliable identification of the GRB hosts and
astrophysical constraints of the evolution of GRB events. Fundamental advances in
understanding GRBs can be achieved with the arcsecond positions, high sensitivity
and spectral calpabilities of AXAF/ACIS. Our TOO program will permit: (1) fast
counterpart identification at other wavelengths; (2) study of the afterglow
spectrum and evolution in both the early (days) and late (months) phases; and (3)
possible detection of X-ray line features. We propose to study 6 bursts localized
by BeppoSAX or RXTE, selecting two of the brightest for detailed multiepoch
spectral study.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
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GRB #3 ACIS-S HETG 10.00
01:59:14.81 -40:40:09.84 GRB000210 ACIS-S NONE 10.00
05:09:31.20 +11:17:06.00 GRB 991216 ACIS-S HETG 10.00
17:04:09.70 +51:47:11.00 GRB000926 ACIS-S NONE 10.00
===================================================================================
Proposal Number: 01100045
Proposal Title: ACIS OBSERVATION OF JUPITER AND THE GALILEAN SATELLITES
PI: GORDON GARMIRE
Subject Category: SOLAR SYSTEM
Abstract: Auroral phenomena in Jupiter are diagnostic of the structure, processes
and energetics of its magnetosphere. Past X-ray observations have revealed
latitudinal and longitudinal asymmetries, with spectra consistent with a model of
sulfur and oxygen ions precipitating onto the Jovian atmosphere. This observation
will provide a clear image of the X-ray emission during a full Jovian rotational
period with spectral resolution sufficient to detect the expected emission
linesif ion precipitations powers the X-ray aurora. Galilean moons immersed in
the magnetosphere may emit X-rays due to particle bombardment, auroral activity
or other process.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
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01:38:49.79 +08:43:13.66 JUPITER ACIS-S NONE 20.15
01:38:54.31 +08:43:35.69 JUPITER ACIS-S NONE 20.15
===================================================================================
Proposal Number: 01108023
Proposal Title: X-RAY EMISSION FROM COMET 10P/BORRELLY DURING THE DEEP SPACE 1
ENCOUNTER
PI: KONRAD DENNERL
Subject Category: SOLAR SYSTEM
Abstract: X-ray emission from comets is now a well established phenomenon. During
the last years a lot of evidence has emerged that the dominant mechanism is
charge exchange between heavy solar wind ions and cometary neutrals. The recent
Chandra ACIS-S observation of Comet C/1999 S4 (LINEAR) has provided the final
proof. Measurements of solar wind parameters, however, have never been made
sufficiently near to a comet to allow a direct comparison with the X-ray flux.
The recent decision of NASA to extend the Deep Space 1 mission for a rendezvous
with comet 19P/Borrelly in Sept 2001 opens, for the first time ever, the unique
opportunity to combine in-situ measurements of the solar wind properties at a
comet with simultaneous X-ray observations. This RfO is submitted as a request
for DDT since the dec
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
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07:54:11.23 +20:45:39.20 COMET 19P/BORRELLY ACIS-S NONE 9.00
07:54:11.23 +20:45:39.20 COMET 19P/BORRELLY ACIS-S NONE 9.00
07:54:11.23 +20:45:39.20 COMET 19P/BORRELLY ACIS-S NONE 9.00
07:54:11.23 +20:45:39.20 COMET 19P/BORRELLY ACIS-S NONE 9.00
***********************************************************************************
NORMAL STARS AND WD
--------------------------------------------------
===================================================================================
Proposal Number: 01200248
Proposal Title: ACIS/HETG SPECTROSCOPY OF THE ACTIVE BINARIES ALGOL & UX ARI
PI: STEPHEN DRAKE
Subject Category: NORMAL STARS AND WD
Abstract: Previous low- and moderate-resolution X-ray spectroscopy of active
binary stars have yielded surprising results concerning the abundances of the
elements in these coronal plasmas, viz., that, in almost every well-studied case,
a solar photospheric abundance plasma model cannot fit the observed spectrum:
e.g., in some stars, Fe abundances of 10% of the solar value have been inferred.
To verify and extend these findings, we propose to observe with the HETG two of
the best-studied such stars, Algol and UX Ari. We will study the detailed
structure of the He-like multiplets of the abundant elements O, Ne, Mg, Si, S,
Ar, Ca, and Fe, and rederive their abundances, and also search for anomalous line
ratios due to effects such as high resonance-line opacity and/or high electron
densities.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
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03:08:10.10 +40:57:20.40 ALGOL ACIS-S HETG 50.00
03:26:35.40 +28:42:54.50 UX ARI ACIS-S HETG 50.00
===================================================================================
Proposal Number: 01200260
Proposal Title: THE FULL T TAURI STAR POPULATION OF THE YOUNG STELLAR CLUSTER IC
348
PI: THOMAS PREIBISCH
Subject Category: NORMAL STARS AND WD
Abstract: We propose to obtain a 50 ksec ACIS-I observation of the young stellar
cluster IC 348. The high sensitivity and spatial resolution of AXAF/ACIS will
allow us, for the first time, to detect X-ray emission from the numerous faint T
Tauri stars in IC 348. This will enable us to identify the {\bf full} population
of T Tauri stars in IC 348, i.e.~down to stellar masses of $0.1\,M_\odot$, by
their X-ray emission. Furthermore, this observation will provide us with X-ray
spectra and lightcurves for a large $(\ge 200)$ and homogeneous sample of T Tauri
stars.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
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03:44:30.00 +32:07:60.00 IC 348 ACIS-I NONE 50.00
===================================================================================
Proposal Number: 01200272
Proposal Title: DIRECT HRC-I IMAGING OF THE COLLIDING WINDS SHOCK IN WR 147
PI: JULIAN PITTARD
Subject Category: NORMAL STARS AND WD
Abstract: Colliding stellar winds in early-type binary systems produce a complex
region of shock-heated plasma with temperatures in excess of 10^7 K, with the
strongest X-ray emission from systems containing Wolf-Rayet (WR) stars. Only in
X-rays do we directly see the shocked gas from the wind collision. Recent high
spatial resolution radio observations of WR 147 have revealed two sources 0.6"
apart, which are believed to be the WR-star and the wind collision shock, both of
which will be X-ray sources. These two sources will be resolvable in a 5ksec
observation with the HRC-I. This observation will provide the first direct
imaging of hot shocked gas in an early-type binary, unambiguously verifying that
the enhanced X-ray emission in early-type binaries is due to a colliding winds
shock.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
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20:36:43.50 +40:21:08.00 WR 147 HRC-I NONE 5.00
===================================================================================
Proposal Number: 01200299
Proposal Title: PHOTOSPHERIC METAL ABUNDANCES IN THE VERY HOT, HYDROGEN-RICH
CENTRAL STARS OF THE PLANETARY NEBULAE NGC1360 AND NGC6853
PI: Thomas Rauch
Subject Category: NORMAL STARS AND WD
Abstract: We propose the spectroscopic observation of the very hot, hydrogen-rich
central stars of the planetary nebulae NGC 1360 and NGC 6853. These are the
brightest of four objects of this spectral subtype which were detected in the
EUVE all-sky survey. Both were detected also by ROSAT. The high-resolution AXAF
spectra will be analyzed together with high-resolution high-S/N optical,
ultraviolet (IUE), extreme ultraviolet(EUVE), and X-ray (ROSAT) data by means of
fully metal-line blanketed NLTE model atmospheres. Principal aim of the AXAF
observations is the first comprehensive determination of light metal (Li - Ca)
abundances as well as of iron group element abundances in central stars of
planetary nebulae.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
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03:33:14.65 -25:52:17.98 NGC 1360 HRC-S LETG 100.00
===================================================================================
Proposal Number: 01200353
Proposal Title: CORONAL STRUCTURE OF THE LONG-PERIOD BINARY: LAMBDA AND
PI: ANDREA DUPREE
Subject Category: NORMAL STARS AND WD
Abstract: AXAF/HETG spectra of the RS CVn binary, Lambda And, will probe the
temperature and density of an unusually hot corona, whose structure has been
outlined through extreme ultraviolet and X-ray studies. Lambda And provides an
important link for understanding the activity/rotation relation, showing evidence
in the photosphere for both high latitude and equatorial spots. The proposed AXAF
grating observation will quantify the coronal emission measure distribution over
the full temperature range, electron densities for at least two distinct
temperatures, and elemental abundances needed to calculate radiative losses.
Coronal abundances from high and low First Ionization Potential will be measured
and compared with well known photospheric abundances.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
23:37:33.80 +46:27:29.30 LAMBDA AND ACIS-S HETG 100.00
===================================================================================
Proposal Number: 01200366
Proposal Title: MEASURING DOPPLER SHIFTS OF X-RAY LINES TO DETERMINE THE STELLAR
WIND X-RAY LOCATIONS IN OB STARS
PI: WAYNE WALDRON
Subject Category: NORMAL STARS AND WD
Abstract: For almost 20 years we have been trying to determine the source of the
X-ray emission in OB stars. It is generally believed that this emission is caused
by a distribution of stellar wind shocks. The AXAF grating spectrometers will
provide the ultimate test of X-ray models. The shock model predicts that X-ray
lines must be Doppler blue-shifted, hence, our primary objective is to measure
these blue-shifts. MARX simulations show that the expected X-ray line shifts will
be at least 4 times the MEG1 energy resolution limit. ASCA observations have
provided stronger constraints on X-ray models, but they have also raised
additional questions (e.g., X-ray abundance anomalies). The large number of X-ray
lines predicted by MARX simulations will allow us to probe X-ray densities and
abundances.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
05:40:45.50 -01:56:34.00 ZETA ORI ACIS-S HETG 60.00
===================================================================================
Proposal Number: 01200367
Proposal Title: EXTENDED X-RAY EMISSION FROM MASSIVE STAR FORMATION REGIONS
PI: EDWARD CHURCHWELL
Subject Category: NORMAL STARS AND WD
Abstract: We propose to obtain images and spectra for the massive star formation
regions (MSFRs) W3, G5.89, and G34.26 using the ACIS-I detector on AXAF. Our
goals are to determine how common X-ray emission is from MSFRs and if the
emission is generally extended and as hard as that observed toward W3. Further,
we wish to use the high spatial resolution of AXAF to resolve the individual UC
HII regions in the W3 complex. Observations of G5.89 and G34.26 will address the
issues of how common extended, hard X-ray emission is from MSFRs, determine if
FeXXV line emission is common and possibly strong enough to account for a
significant fraction of the FeXXV disk emission from the Galaxy.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
02:25:38.10 +62:05:52.50 W3B ACIS-I NONE 18.50
02:25:38.10 +62:05:52.50 W3B ACIS-I NONE 21.50
===================================================================================
Proposal Number: 01200382
Proposal Title: THE SOURCE OF X-RAYS IN THE HR 1442 SYSTEM
PI: FREDERICK WALTER
Subject Category: NORMAL STARS AND WD
Abstract: HR 1442 is a pair of B9 IV stars associated with the Taurus star
formation region. It is also one of the brightest X-ray sources in this star
formation region. ROSAT HRI observations could not resolve the pair. Ground based
observations shows that one of the B stars has an infrared excess, a lithium
absorption line, and may have a circumstellar disk. There is also a fainter
IR-bright star nearby. We propose an HRC-I imaging observation to resolve the
source(s) of the X-rays in this system. This will assist in elucidating the
nature of the peculiar B star.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
04:33:32.70 +18:01:00.00 HR 1442 HRC-I NONE 5.00
===================================================================================
Proposal Number: 01200472
Proposal Title: FLUORESCENCE AND OPTICAL DEPTH: NEW PROBES OF CORONAL GEOMETRY
PI: JEREMY DRAKE
Subject Category: NORMAL STARS AND WD
Abstract: Our proposed 100ks LETG+ACIS-S observation of the X-ray bright active
star sigma Gem will yield a wealth of X-ray plasma line diagnostics that will
give us a giant leap forward in our understanding of its coronal densities,
abundance anomalies and emission measure distribution. Unfortunately, there is
one very basic unanswered question in the physics of active stellar coronae that
the usual plasma diagnostics cannot address directly: What are the spatial
characteristics of stellar coronae---the scale height and filling factor? What do
other stellar coronae actually look like? We will provide the first direct
spectroscopic answers to this question through two novel diagnostics of coronal
geometry: photospheric fluorescence and resonance line optical depths.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
07:43:18.40 +28:53:12.10 SIGMA GEM ACIS-S LETG 100.00
===================================================================================
Proposal Number: 01200475
Proposal Title: FK COM: SHROUDED IN MYSTERY
PI: DEREK BUZASI
Subject Category: NORMAL STARS AND WD
Abstract: FK Com is a single G-type giant rotating near the breakup velocity
which is considered to be a recently coalesced binary. While generally displaying
extreme levels of activity, FK Com is highly variable and surprisingly
underluminous at X-ray wavelengths. This observed deficiency may be due either to
obscuring material around the star, or to a dynamo mechanism which differs from
that operating in other cool stars. We propose to observe FK Com and two similar
stars, HD 199178 and LW Hya, to address this issue and others, such as the
contribution of flaring to the observed X-ray luminosity and the question of
whether or not the corona is corotating. In the case of LW Hya, we propose to use
ACIS-I for a quick first look, while we will use HETG for an in-depth study of FK
Com and HD 199178.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
13:30:46.90 +24:13:58.90 FK COM/HD 117555 ACIS-S HETG 40.00
===================================================================================
Proposal Number: 01200495
Proposal Title: X-RAY EMISSION AT THE BOTTOM OF THE MAIN SEQUENCE
PI: THOMAS FLEMING
Subject Category: NORMAL STARS AND WD
Abstract: We propose to obtain AXAF ACIS-S-BI images of a sample of low mass
stars and brown dwarfs. Until now, the lowest-mass dwarf detected in X-rays had
been VB 8. Given the improved sensitivity of AXAF over previous missions, we are
confident that coronal X-ray emission can now be detected in the very lowest mass
stars and substellar objects known. Therefore, the objective of this proposal is
to make such detections and thereby establish the existence of magnetic activity
at the very bottom of the main sequence and beyond. Our target list includes the
brown dwarfs Kelu-1 and BRI 0021-0214 along with the very low mass stars LHS 2924
and VB 10. We also request a short ACIS-S-BI image of the known X-ray source VB 8
as a prelude to future AXAF LETG observations.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
16:55:35.40 -08:23:39.90 VB 8 ACIS-S NONE 9.00
19:16:57.10 +05:09:04.90 VB 10 ACIS-S NONE 13.00
===================================================================================
Proposal Number: 01200572
Proposal Title: X-RAYS FROM THE RHO OPHIUCHI YOUNG STAR CLUSTER
PI: THIERRY MONTMERLE
Subject Category: NORMAL STARS AND WD
Abstract: The rho Ophiuchi cloud is one of the richest and nearest star forming
regions with hundreds of young stellar objects (YSOs) representing all stages of
early stellar evolution. It is a superb laboratory for the study of X-ray
emission from YSOs with extensive multiwavelength data. AXAF observations will
lead to insights concerning the dispersal of circumstellar disks, the impact of
ionizing radiation and particles on disks, and the evolution of X-ray emission.
We propose a mosaic of ACIS fields covering one square degree, designed to give a
uniform sensitivity despite large changes in cloud extinction.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
16:25:31.70 -24:25:03.00 OPHIUCHI MOSAIC #1 ACIS-I NONE 5.00
16:26:29.90 -24:32:33.00 OPHIUCHI MOSAIC #2 ACIS-I NONE 5.00
16:26:29.90 -24:17:33.00 OPHIUCHI MOSAIC #4 ACIS-I NONE 5.00
16:27:28.00 -24:10:03.00 OPHIUCHI MOSAIC #8 ACIS-I NONE 5.00
16:28:26.20 -24:47:33.00 OPHIUCHI MOSAIC #9 ACIS-I NONE 5.00
16:28:26.20 -24:32:33.00 OPHIUCHI MOSAIC #10 ACIS-I NONE 5.00
16:28:26.20 -24:17:33.00 OPHIUCHI MOSAIC #11 ACIS-I NONE 5.00
===================================================================================
Proposal Number: 01200574
Proposal Title: THE END OF STELLAR CORONAE?
PI: Gibor Basri
Subject Category: NORMAL STARS AND WD
Abstract: Almost all stars are X-ray emitters. Convective stars are thought to
have analogs of the solar corona, caused by magnetic activity which in turn is
produced by a dynamo. There are reasons to believe that the dynamo and coronal
heating could change character near the bottom of the main sequence. We get to
the heart of this by going to the very bottom of the main sequence, and below to
the brown dwarf regime. We test 2 of the nearest known such objects to see if
they lie beyond the end of the realm of stellar coronae.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
03:39:34.70 -35:25:50.00 LP 944-20 ACIS-S NONE 40.00
===================================================================================
Proposal Number: 01200585
Proposal Title: LETG OBSERVATION OF THE HOT WHITE DWARF GD 246
PI: JEAN DUPUIS
Subject Category: NORMAL STARS AND WD
Abstract: We propose an observation of the bright hot white dwarf GD 246 with the
Low Energy Transmission Grating. Our goal is to make use of the high spectral
resolution offered by the LETG to unambiguously identify the chemical elements
responsible for the short wavelength opacity in GD 246.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
23:12:21.40 +10:47:05.00 GD 246 HRC-S LETG 40.00
===================================================================================
Proposal Number: 01200256
Proposal Title: A COMPREHENSIVE INVESTIGATION OF X-RAY EMISSION FROM
INTERMEDIATE MASS STARS
PI: JEFFREY LINSKY
Subject Category: NORMAL STARS AND WD
Abstract: Although X-rays have been detected from essentially all types of stars,
one portion of the X-ray H-R Diagram remains an enigma. Despite large surveys
using Einstein and ROSAT, it is still not clear whether or not main sequence
stars of intermediate mass (spectral types B3--A7) are intrinsic X-ray sources.
Stars cooler than spectral type F0 are coronal X-ray sources and O3--B3 stars are
wind X-ray sources, but are the intermediate mass stars intrinsic X-ray sources
and how are they heated? We will exploit AXAF's three unique properties (high
resolution imaging, high energy resolution, and high sensitivity detectors with
very low background) to determine whether or not the intermediate mass stars are
intrinsic X-ray sources and to study the nature of the X-ray emitting plasma.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
13:06:16.70 -48:27:47.80 HD 113703 ACIS-S NONE 12.50
14:45:57.64 -44:52:03.01 HD 129791 ACIS-S NONE 6.90
15:17:30.85 -58:48:04.30 HD 135379 ACIS-S NONE 20.00
===================================================================================
Proposal Number: 01200603
Proposal Title: X-RAY EMISSION FROM WOLF-RAYET STARS: THE COLLIDING WIND SHOCK
SYSTEM GAMMA VELORUM
PI: STEPHEN SKINNER
Subject Category: NORMAL STARS AND WD
Abstract: The powerful winds of Wolf-Rayet (WR) stars generate strong X-rays via
shock processes and also serve as an important source of chemical enrichment of
the interstellar medium. We propose to obtain a high resolution X-ray spectrum of
the colliding wind shock binary system Gamma Velorum (WC8 + O8), containing the
closest WR star known. The spectrum will be rich in emission lines, providing
information on mass loss parameters and shock geometry as well as metal
abundances that can be used to test evolutionary models of massive stars.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
08:09:32.00 -47:20:12.10 HD 68273 ACIS-S HETG 65.00
===================================================================================
Proposal Number: 01200619
Proposal Title: SHOCKED STELLAR WINDS IN PLANETARY NEBULAE
PI: YOU-HUA CHU
Subject Category: NORMAL STARS AND WD
Abstract: Planetary nebulae (PNe) are expected to contain two types of X-ray
sources: a hot central star with temperature between 100,000 and 200,000 K, and a
shocked fast stellar wind at temperatures between 10$^6$ and 10$^8$ K. The
shocked fast wind, if detected, allows us to peer into the PN interior and
determine its physical conditions directly. We request ACIS-S observations of NGC
6543 (Cat's Eye Nebula) and NGC 7293 (Helix Nebula) in order to search for and
analyze their shocked fast winds. NGC 6543 is the only PN for which diffuse X-ray
emission has been previously reported and can be detected by the AXAF. NGC 7293
is the nearest PN, and hence provides the most promising case for which the hard
and soft X-ray components may be spatially resolved and distinguished.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
17:58:33.30 +66:37:59.20 NGC 6543 ACIS-S NONE 50.00
22:29:38.50 -20:50:18.00 NGC 7293 ACIS-S NONE 12.00
22:29:38.50 -20:50:18.00 NGC 7293 ACIS-S NONE 38.00
===================================================================================
Proposal Number: 01200684
Proposal Title: RESOLVING THE X-RAY SPECTRUM OF THE EXTREMELY MASSIVE,
SUPERLUMINOUS STAR ETA CARINAE WITH AXAF
PI: MICHAEL CORCORAN
Subject Category: NORMAL STARS AND WD
Abstract: Eta Car may be the most massive and luminous star in the Galaxy
(Davidson and Humphreys 1997). It has remained a mystery shrouded behind a thick
massive cloud of ejecta. X-ray emission is both a probe through this curtain and
a probe of this curtain. AXAF grating spectroscopy will help us make the next
leap forward by addressing currently unresolved questions about the velocity
field near the star, the stellar abundances and possible abundance gradients in
the circumstellar ejecta, the processes of line excitation, and the nature of the
hard X-ray emission and the nature of the star (or stars).
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
10:45:02.00 -59:40:49.00 ETA CAR ACIS-S HETG 100.00
===================================================================================
Proposal Number: 01200687
Proposal Title: X-RAY PROPERTIES OF VERY MASSIVE STARS WITH VERYDIFFERENT
METALLICITIES:THE ``STARBURSTS'' NGC 3603 AND NGC 346
PI: MICHAEL CORCORAN
Subject Category: NORMAL STARS AND WD
Abstract: We propose to use ACIS-I to image the centers of the starburst
analogues NGC 3603 in the Galaxy and NGC 346 in the SMC. This study will enable
us to definitively determine the effects of abundance on X-ray emission, will
provide X-ray luminosities for nearly 100 stars, will provide X-ray spectra for
dozens of massive stars, and will enable us to examine the nature of diffuse
emission and SNR on the local ISM.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
11:15:07.20 -61:15:35.20 NGC 3603 ACIS-I NONE 50.00
===================================================================================
Proposal Number: 01200704
Proposal Title: HARD X-RAY SEARCH FROM CLASS 0 PROTOSTARS
PI: KATSUJI KOYAMA
Subject Category: NORMAL STARS AND WD
Abstract: We propose to observe the Orion Molecular Clouds, OMC 2 and OMC 3, with
the ACIS-I instrument. With ASCA, these regions are found to exhibit hard X-ray
emissions, possiblly from embedded Class 0 and Class I protostars. Our goal is to
investigate; (1) when a star begins to emit X-rays, (2) what is the difference in
X-rays (spectrum and time variability) between Class 0 and Class I, and the other
phases of star formation (ClassII, III), and (3) what is the X-ray emission
mechanism in the protostar phase.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
05:35:19.98 -05:05:29.80 OMC2--3 ACIS-I NONE 100.00
===================================================================================
Proposal Number: 01200705
Proposal Title: RESOLVING EMBEDDED X-RAY OBJECTS IN RHO OPH CLOUD CORE
PI: KATSUJI KOYAMA
Subject Category: NORMAL STARS AND WD
Abstract: With the ASCA observations of the Rho Oph dark cloud, we found variable
hard X-ray emission from Class I sources. A Class I (EL29) shows a flare like
TTSs, other (WL6) varies sinusoidally, suggesting rotation period, and the other
(YLW15) exhibit quasi-periodic flares, suggestive for the star-disk magnetic
connection. Non X-ray emitting Class I is also found. Our proposal is, with no
source confusion problem, to confirm these variety of X-ray activity, to search
for X-rays from other Class Is, as well as new X-ray emitting young stellar
objects, using ACIS with the high spatial resolution up to 10 keV energy.
Together with the radio search of bipolar structure, and comparison of TTSs, our
goal is to give strong constrain on the evolution and structure of protostars.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
16:27:17.18 -24:34:39.00 RHO OPH CORE ACIS-I NONE 100.00
===================================================================================
Proposal Number: 01200720
Proposal Title: CORONAL SPECTROSCOPY OF THE F0 SUPERGIANT CANOPUS: PROPERTIES OF
INTERMEDIATE MASS STAR CORONAE AFTER THE HE FLASH
PI: ALEXANDER BROWN
Subject Category: NORMAL STARS AND WD
Abstract: Canopus (F0 Ib), the nearest (96 pc) supergiant, is a He-burning,
post-red supergiant star that recently redeveloped a 20 million K corona and
powers this corona at log Lx = 29.8 erg/s despite having a very thin convection
zone. The coronae of Canopus and similar stars are remarkably constant,
suggesting that while, the magnetic loops are efficiently heated, there is little
interaction between the loops. Canopus is the brightest late-type supergiant in
X-rays. We propose a 100 ksec HETG observation to measure the detailed coronal
temperature and EM distributions for this unusual type of corona. Coronal
abundances and densities will be estimated. In conjunction with HST/STIS spectra,
we will investigate the coronal energy balance and heating mechanisms, and
magnetic loop properties.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
06:23:57.10 -52:41:44.40 HD 45348 ACIS-S HETG 100.00
===================================================================================
Proposal Number: 01200767
Proposal Title: ACIS IMAGING SPECTROSCOPY OF THE RHO OPHIUCHUS A CLOUD
PI: MARC GAGNE
Subject Category: NORMAL STARS AND WD
Abstract: Einstein, ROSAT and ASCA observations of the rho Ophiuchus star-forming
region have revealed X-ray flares, very hot plasma, and quasi-periodic
variability from embedded young stellar objects, suggesting that some of the
X-rays are produced by interactions between an accretion disk and large-scale
magnetic fields. We propose to obtain a 100-ks ACIS-I exposure of rho Oph A in
order to model X-ray spectra and light curves of YSOs spanning a wide range of
masses and accretion rates. These include the magnetic B3 star S1, 2 Herbig Ae/Be
stars, 2 class I protostars, 8 classical T Tauri stars, 3 weak-lined T Tauri
stars, along with 40-50 new X-ray sources. AXAF's spatial resolution and
effective area will allow us to model X-ray spectra of embedded sources not
attainable with ROSAT or ASCA.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
16:26:34.20 -24:23:27.80 RHO OPH A ACIS-I NONE 100.00
===================================================================================
Proposal Number: 01200878
Proposal Title: ARE B STAR X-RAY SOURCES WIND-CORONAL HYBRIDS?
PI: DAVID COHEN
Subject Category: NORMAL STARS AND WD
Abstract: We propose to use the high spectral resolution of both the LETG and
HETG to address several outstanding questions regarding X-ray production in B
stars, including: Are coronal and wind mechanisms operating together in some B
stars? Does the chaotic wind of tau Sco produce significant non-thermal emission
? What is the ionization balance in the stellar winds and how are X-rays
reprocessed in the ambient wind? These questions can be addressed directly thanks
to the ability afforded by AXAF to apply spectral diagnostic techniques used in
the laboratory to X-ray astrophysics. These diagnostics include (1) line profile
analysis, (2) density-sensitive line ratios, (3) continuum analysis, (4)
temperature-sensitive line ratios, and (5) inner-shell emission and absorption.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
16:35:52.90 -28:12:56.50 TAU SCO ACIS-S HETG 15.00
16:35:52.90 -28:12:56.50 TAU SCO ACIS-S HETG 65.00
===================================================================================
Proposal Number: 01200893
Proposal Title: HIGH-RESOLUTION SPECTRAL DIAGNOSTICS OF O-STAR X-RAY SOURCES
PI: JOSEPH CASSINELLI
Subject Category: NORMAL STARS AND WD
Abstract: In the case of the fast O-star winds, the spectrometers on AXAF will
provide for the first time the spectral resolution needed to derive velocities of
the X-ray emitting material, significant constraints on the location of the
emitting regions, and accurate characterizations of the temperature and density
conditions of the X-ray sources. The wind absorption occurs not only by
bound-free transistions, but by bound-bound inner shell transistions. Thus,
diagnostic modelling of the AXAF spectra will provide new information not only
about the state of the hot emitting plasma, but also about of the cool wind. We
propose AXAF transmission grating observations of 3 bright O-stars: Iota Ori
(LETG), Zeta Pup (METG/HETG), and Delta Ori (LETG).
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
05:32:00.30 -00:17:57.00 DELTA ORI ACIS-S HETG 50.00
08:03:35.10 -40:00:12.10 ZETA PUP ACIS-S HETG 75.00
===================================================================================
Proposal Number: 01200951
Proposal Title: COORDINATED AXAF AND HST SPECTROSCOPY OF FLARES ON PROXIMA
CENTAURI
PI: JEFFREY LINSKY
Subject Category: NORMAL STARS AND WD
Abstract: AXAF provides the first opportunity to study the dynamics of flaring
plasma using the powerful tools of X-ray spectroscopy. We request AXAF
observations of the nearest flare star, Proxima Centauri (M6 Ve), as part of a
UNIQUE OPPORTUNITY for simultaneous X-ray and UV flare spectroscopy. We have 8
orbits (about 46 ks) of HST Cycle 8 GTO time (June 1999-May 2000) for high
resolution UV spectra of Prox Cen in the continuous viewing zone. Simultaneous
AXAF grating spectra will permit us to study the plasma motions and EM(T) with
high time resolution to characterize the flare energetics at all layers in the
atmosphere and to determine whether the 2-ribbon flare model as appropriate.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
14:29:42.90 -62:40:46.10 PROXIMA CENTAURI ACIS-S NONE 16.00
14:29:42.90 -62:40:46.10 PROXIMA CENTAURI ACIS-S NONE 30.00
14:29:42.90 -62:40:46.10 PROXIMA CENTAURI ACIS-S HETG 46.00
===================================================================================
Proposal Number: 01200957
Proposal Title: ACIS STUDY OF THE PERSEUS STAR FORMING CLOUD
PI: ERIC FEIGELSON
Subject Category: NORMAL STARS AND WD
Abstract: The Perseus cloud (d = 320 pc) is the nearest giant molecular cloud and
harbors two rich clusters of pre-main sequence stars: NGC 1333 and IC 348. The
proposed ACIS exposures will provide the deepest study of young stellar X-ray
emission ever achieved and should detect about 400 sources. This study will
improve the census of young stars in the clusters; probe the relationship between
X-rays, disks and outflows; and investigate X-ray properties as a function of
stellar luminosity, mass and especially age. The findings should give insight
into possible effects of magnetic activity on protostars and T Tauri stars, such
as X-ray and particle irradiation of the disk.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
03:29:05.60 +31:19:19.00 NGC 1333 ACIS-I NONE 50.00
===================================================================================
Proposal Number: 01200018
Proposal Title: OBSERVATIONS WITH LETGS OF THE ECLIPSING BINARY ALGOL
PI: PETER PREDEHL
Subject Category: NORMAL STARS AND WD
Abstract: Algol is a bright eclipsing binary which is well suited to study the
geometry, the differential emission measure distribution, and the electron
density distribution of the coronal components.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
03:08:10.10 +40:57:20.50 ALGOL HRC-S LETG 80.00
===================================================================================
Proposal Number: 01200028
Proposal Title: STELLAR CORONAL SPECTROSCOPY OF STAR-FORMING REGIONS: ORION
PI: CLAUDE CANIZARES
Subject Category: NORMAL STARS AND WD
Abstract: HETGS spectra will reveal a wealth of information on the temperature
and density structure of stellar coronae and winds. The Trapezium in Orion
contains many hot and cool young stars. HETGS observations of Orion will
simultaneously obtain dispersed spectra of the brightest objects (hot stars), and
CCD PHA spectra of young cool stars. This observation will also test the
abilities of multiple source spectroscopy with HETGS.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
05:35:15.00 -05:23:29.50 TRAPEZIUM ACIS-S HETG 40.00
05:35:15.00 -05:23:29.30 TRAPEZIUM ACIS-S HETG 33.00
===================================================================================
Proposal Number: 01200029
Proposal Title: STELLAR CORONAL SPECTROSCOPY OF COOL STARS
PI: CLAUDE CANIZARES
Subject Category: NORMAL STARS AND WD
Abstract: HETGS spectra will reveal a wealth of information on the temperature
and density structure of stellar coronae. In addition, rotational or eclipse
modulation can be used to further determine geometric structure. Two RS CVn stars
will be observed with HETG and ACIS-S: AR Lac, and II Peg. AR Lac data will be
taken through primary eclipse to map emitting structures. One pre-main-sequence
star, TW Hya, which is a nearby, isolated, classical T Tauri object, will provide
detail on the nature of young-star X-ray emission.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
11:01:52.00 -34:42:16.00 TW HYA ACIS-S HETG 50.00
22:08:40.80 +45:44:32.00 AR LAC-4 ECLIPSE (2) ACIS-S HETG 35.00
22:08:40.80 +45:44:32.00 AR LAC-1 ECLIPSE (1 ACIS-S HETG 35.00
22:08:40.80 +45:44:32.00 AR LAC-3 LAST QUAD ( ACIS-S HETG 7.50
22:08:40.80 +45:44:32.00 AR LAC-6 LAST QUAD ( ACIS-S HETG 7.50
22:08:40.80 +45:44:32.00 AR LAC-2 FIRST QUAD ACIS-S HETG 7.50
22:08:40.80 +45:44:32.00 AR LAC-5 FIRST QUAD ACIS-S HETG 7.50
23:55:04.00 +28:38:01.00 II PEG (HD 224085) ACIS-S HETG 1.00
23:55:04.00 +28:38:01.00 II PEG (HD 224085) ACIS-S HETG 50.00
===================================================================================
Proposal Number: 01200031
Proposal Title: DEEP ACIS IMAGING OF THE CORE OF THE PLEAIDES CLUSTER
PI: JEFFREY LINSKY
Subject Category: NORMAL STARS AND WD
Abstract: We propose to obtain a single, 60 ksec, ACIS-I exposure of the core of
the 100 million year-old Pleiades open cluster. The 16x16 arcmin ACIS-I field of
view will contain at least 20 known ROSAT PSPC sources for which ACIS-I will
provide simultaneous, high signal-to-noise 0.5-7 keV light curves and
low-resolution spectra. The ACIS-I image will also reveal 100-200 previously
unknown X-ray sources. Most will be associated with low-mass cluster members
including a few candidate brown dwarfs. The ACIS data will be used with recently
derived rotational periods to test rotation-activity at the low end of the
zero-age main sequence. The ACIS spectra and light curves will allow modeling of
X-ray flares and coronal heating for these young, active stars.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
03:46:46.00 +24:04:06.00 PLEIADES ACIS-I NONE 23.75
03:46:46.00 +24:04:06.00 PLEIADES ACIS-I NONE 36.25
===================================================================================
Proposal Number: 01200032
Proposal Title: AXAF GRATING SPECTROSCOPY OF ACTIVE BINARIES
PI: JEFFREY LINSKY
Subject Category: NORMAL STARS AND WD
Abstract: We propose to observe two active binaries with the AXAF HETGS and
LETGS. TZ CrB is a G0 V + G0 V RS CVn binary. The HETGS observation will span an
entire 1.14-d orbital period and will probably include one large flare. The HETGS
line profiles may reveal high-velocity material ejected at the onset of a flare.
Density and temperature-sensitive line ratios obtained at different orbital
phases will be used to map the coronal geometry of TZ CrB. 44 Boo is an
eclipsing, W UMa-type contact binary. The LETGS observation of 44 Boo will span
no less than two 0.27-d orbital periods and will be used to perform coronal
eclipse mapping and to investigate flares. Moreover, 44 Boo's maximum radial
velocity separation of 230 km/s should be resolved in the longer wavelength LETG
line profiles.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
15:03:47.30 +47:39:14.60 44 BOO ACIS-S HETG 60.00
16:14:41.60 +33:51:35.00 TZ CRB ACIS-S HETG 85.00
===================================================================================
Proposal Number: 01200034
Proposal Title: AXAF GRATING SPECTROSCOPY OF ACTIVE SINGLE STARS
PI: JEFFREY LINSKY
Subject Category: NORMAL STARS AND WD
Abstract: We propose to observe two active late-type single dwarfs with the AXAF
HETGS. AB Dor is a Pleiades-age K2 V rapid rotator at a distance of 15 pc. AB Dor
exhibits large-amplitude long-duration flares and rotationally modulated activity
at many wavelengths. The HETGS observation of AB Dor will span an entire 0.51-d
rotational period. AU Mic is a very active M1 V flare star at a distance of 10
pc. AB Dor and AU Mic are prototypes for extreme main-sequence magnetic activity.
The principal objectives of the HETGS observations are (i) to obtain
time-resolved X-ray spectra of flares and (ii) to obtain high signal-to-noise,
high-resolution spectra of very hot coronal sources to test optically thin
collisional ionization equilibrium plasma codes. Supporting ground-based
observations are planned.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
05:28:44.80 -65:26:56.00 AB DOR ACIS-S HETG 60.00
20:45:09.33 -31:20:24.00 AU MIC ACIS-S HETG 60.00
===================================================================================
Proposal Number: 01200039
Proposal Title: YOUNG STARS IN THE ORION TRAPEZIUM CLUSTER
PI: GORDON GARMIRE
Subject Category: NORMAL STARS AND WD
Abstract: The Orion Trapezium cluster is the richest and densent cluster of
pre-main sequence stars in the solar neighborhood, and the nearest region of
high-mass star forming region. It is a superb laboratory for study of X-ray
emission from protostars, classical and weak-lined T Tauri stars. The proposed
observation should detect hundreds of stars, dozens of powerful
magnetically-induced flares. X-ray emission from embedded protostars and massive
OB stars will also be studied. The relationaships between X-ray emission and
other stellar properties, and the influence of magnetic activity on star and
planet formation, will be investigated.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
05:35:15.00 -05:23:20.00 TRAPEZIUM CLUSTER ACIS-I NONE 13.74
===================================================================================
Proposal Number: 01200043
Proposal Title: X-RAYS FROM THE YOUNGEST STARS IN THE CORONA AUSTRALIS CLOUD
PI: GORDON GARMIRE
Subject Category: NORMAL STARS AND WD
Abstract: Low-mass pre-main sequence stars from protostars to post-T Tauri stars
have X-ray emission considerably above that seen in older stars. Powerful flares
from Class I protostars are particularly important and poorly understood. The
core of the nearby star forming cloud in Corona Australis contains several X-ray
emitting protostars as well as T Tauri and Herbig Ae/Be stars with associated
outflows.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
19:01:50.60 -36:57:30.00 CRA CLOUD CORE ACIS-I NONE 20.00
===================================================================================
Proposal Number: 01200050
Proposal Title: YOUNG STARS AND OUTFLOWS IN LYNDS 1641
PI: GORDON GARMIRE
Subject Category: NORMAL STARS AND WD
Abstract: The Orion molecular cloud contains a wide range of star forming
environments, from rich high-mass clusters to distributed low-mass star
formation. This observation focuses on the latter. The field includes a number of
T Tauri stars, the Herbig Ae/Be star V380, and the high-velocity Herbig-Haro
objects HH-1 and HH-2. Soft X-rays from the outflow, or hard Fe-K emission from a
diffuse plasma, may also be detected. A short exposure will resolve the whether
the B9 star HD 37001 or a nearby M4 star is responsible for the ROSAT source
RX0535-0633.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
05:35:08.00 -06:33:47.00 HD 37001 ACIS-I NONE 2.00
05:36:22.80 -06:46:09.00 HH 1 ACIS-S NONE 20.00
===================================================================================
Proposal Number: 01200051
Proposal Title: ACIS OBSERVATION OF 30 DORADUS
PI: GORDON GARMIRE
Subject Category: NORMAL STARS AND WD
Abstract: 30 Doradus is a bright star-forming region in the LMC. It contains
over 100 OB stars and has been observed to be a source of diffuse X-rays. This
AXAF observation will measure spectra of young stars and of the diffuse emission.
Energy balance and emission processes in the nebula will be studied.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
05:38:42.85 -69:06:03.00 30 DORADUS ACIS-I NONE 2.00
05:38:42.85 -69:06:03.00 30 DORADUS ACIS-I NONE 28.00
===================================================================================
Proposal Number: 01200059
Proposal Title: EMISSION FROM LATE-TYPE STARS
PI: STEPHEN MURRAY
Subject Category: NORMAL STARS AND WD
Abstract: Our proposed program to understand the X-ray emission from late-type
stars will address three important issues: i) establish whether the ``solar
analogy'' is invariably appropriate (and under what circumstance it may not
apply), ii) determine coronal characteristics and their dependence on the
properties of the underlaying stars (including rotation, color, and metallicity),
and iii) understand the variation of activity levels at the low-mass end of the
main sequence, where the convection zone may penetrate to near the stellar
center.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
08:39:11.90 +65:01:11.00 PI-1 UMA HRC-S LETG 30.00
10:19:38.00 +19:52:14.30 AD LEO HRC-S LETG 10.00
===================================================================================
Proposal Number: 01200060
Proposal Title: EMISSION FROM EARLY-TYPE STARS
PI: STEPHEN MURRAY
Subject Category: NORMAL STARS AND WD
Abstract: These observations will investigate the origin of X-ray emission from
early-type stars and seek to discriminate between existing models which can be
grossly characterized as either ``coronal'' or ``shocked wind''. For the nearest
examples of this stellar class, the HRC-I should be able to distinguish between
X-ray emission from within the stellar wind ``bubble'' and that emanating from
the surrounding interstellar medium. High resolution spectroscopic observations
with the HRC-S+LETGS can determine the variation of the soft X-ray absorption as
a function of bolometric luminosity, spectral type, and mass loss rate. This
absorption holds the observational key to understanding the relative position of
the X-ray source(s) and the ambient massive cool winds which emanate from OB
stars.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
08:03:35.10 -40:00:12.00 Z eta Pup HRC-S LETG 25.00
===================================================================================
Proposal Number: 01200061
Proposal Title: STAR FORMING REGIONS AND YOUNG CLUSTERS
PI: STEPHEN MURRAY
Subject Category: NORMAL STARS AND WD
Abstract: Our observations of star formation regions and young compact clusters
will address: i) stellar collapse and commencement of nuclear burning -
associated high X-ray activity makes such observations one of the best techniques
for selecting young stars in molecular clouds for detailed study; and ii) the
question of the existence of the X-ray activity in low mass stars at the onset of
full convection - the problem of conflicting evidence arising from studies of
field M dwarfs can be addressed by observing young open clusters cores over a
range of ages and by examining the behavior of Lx and Lx/L_bol with spectral type
and/or rotation.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
05:35:16.70 -05:23:24.00 ORION TRAPEZIUM SFR HRC-I NONE 69.00
07:58:07.10 -60:45:36.00 NGC 2516 HRC-I NONE 49.00
23:23:25.80 +58:48:53.40 CAS A HRC-I NONE 50.00
23:23:27.85 +58:48:42.10 CAS A HRC-S NONE 50.00
===================================================================================
Proposal Number: 01200126
Proposal Title: OBSERVATIONS OF STELLAR CORONAE WITH LETGS
PI: PETER PREDEHL
Subject Category: NORMAL STARS AND WD
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
07:34:37.60 +31:52:10.88 YY GEM HRC-S LETG 58.00
===================================================================================
Proposal Number: 01200128
Proposal Title: OBSERVATIONS OF STELLAR CORONAE WITH LETGS
PI: ALBERT BRINKMAN
Subject Category: NORMAL STARS AND WD
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
14:39:36.20 -60:50:07.00 ALPHA CEN HRC-S LETG 80.00
===================================================================================
Proposal Number: 01200142
Proposal Title: HIGH RESOLUTION SPECTROSCOPY OF WHITE DWARFS
PI: STEPHEN MURRAY
Subject Category: NORMAL STARS AND WD
Abstract: H1504+65 is the hottest white dwarf star known. Its atmosphere appears
to be devoid of H or He, perhaps from mass loss during several cycles through the
red giant phase. If so this star reveals directly the products of nuclear burning
in the core of its progenitor. A high resolution spectrum can identify the
elements in the photosphere. If present, the detection of Ne and its abundance
will provide important information on the physical conditions in the core.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
15:02:08.10 +66:12:24.00 H1504+65 HRC-S LETG 25.00
***********************************************************************************
WD BINARIES AND CV
--------------------------------------------------
===================================================================================
Proposal Number: 01300181
Proposal Title: THE NATURE OF THE SUPERSOFT X-RAY SOURCE RXJ0439.8-6809
PI: Andre Van Teeseling
Subject Category: WD BINARIES AND CV
Abstract: The supersoft X-ray source RXJ0439.8-6809 is either the hottest known
pre-white dwarf or an accreting double-degenerate white-dwarf binary. In the
first case, RXJ0439.8-6809 puts strong constraints on the evolution of post-AGB
stars; in the second case, it may have the shortest orbital period among all
known accreting binaries. We propose to obtain a 40 ksec HRC-S+LETG observation,
which will accurately determine the nature of the X-ray spectrum and the
corresponding physical parameters, provide an accurate Rayleigh-Jeans
extrapolation necessary to interprete the scheduled HST observations, possibly
prove the white-dwarf nature of the X-ray source by detecting NeVIII absorption
edges, and at best detect the predicted orbital period of a few minutes.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
04:39:49.60 -68:09:01.00 RX J0439.8-6809 HRC-S LETG 40.00
===================================================================================
Proposal Number: 01300218
Proposal Title: ESTABLISHING THE TRUE NATURE OF RX J0925.7-4758 WITH AXAF
PI: Hendrik Hartmann
Subject Category: WD BINARIES AND CV
Abstract: This proposal is a continuation of a series of studies of the Supersoft
Source RXJ0925.7-4758. Earlier studies involve spectra obtained by ROSAT, ASCA
and Beppo-SAX. Many questions regarding the nature of RXJ0925.7-4758 have arisen
that could not be answered using the available observations. This is due to the
limited spectral resolution of ASCA SIS and Beppo-SAX LECS. We believe that the
high spectral resolution of AXAF MEG/ACIS-S will definitively establish the true
nature of RXJ0925.7-4758. Fitting grids of detailed model spectra, available to
the investigators, will tightly constrain parameters like temperature, gravity
and abundances. Thus we will be able to decide between a white dwarf, neutron
star or black hole as a model for RXJ0925.7-4758.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
09:25:46.20 -47:58:16.60 RX J0925.7-4758 ACIS-S HETG 60.00
===================================================================================
Proposal Number: 01300301
Proposal Title: THE TEMPERATURE STRUCTURE IN THE ACCRETION REGION OF AM HERCULIS
PI: KLAUS REINSCH
Subject Category: WD BINARIES AND CV
Abstract: We propose to obtain a 24 ksec HRS-C LETG observation of AM Her, the
prototype system of the magnetic cataclysmic variables. High resolution
spectroscopy in the 0.1-6 keV energy range will allow us to quantitatively
compare the soft X-ray spectrum with detailed accretion-heated model atmospheres.
Absorption and emission edges of C, N, O, and Ne will provide diagnostic
information on the ionization and temperature structure of the accretion region
and on the structure, density, and homogenity of the accretion flow and its
temporal fluctuations. There is good evidence from observations and theory that
with the AXAF LETG we will for the first time be able to resolve the long-sought
signatures of the temperature inversion in the heated atmosphere which are not
visible in the EUV.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
18:16:13.30 +49:52:03.00 AM HER HRC-S LETG 24.00
===================================================================================
Proposal Number: 01300474
Proposal Title: HIGH-RESOLUTION X-RAY SPECTROSCOPY OF SS CYGNI IN QUIESCENCE
PI: PETER WHEATLEY
Subject Category: WD BINARIES AND CV
Abstract: We propose an AXAF HETGS observation of the brightest dwarf nova SS
Cygni in its normal quiescent state. The unprecedented spectral resolution
afforded by AXAF will make this the first observation of a hard-X-ray
cataclysmic-variable boundary layer in which it is possible fully to resolve
individual lines (other than Fe-K). The spectrum will allow us to measure the
temperature distribution of the shock-heated plasma and constrain its density and
elemental abundances. Measurement of these quantities will form the observational
basis on which to build a theoretical understanding of the complex shocks which
form in the strongly-shearing flow of the boundary layer.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
21:42:42.00 +43:35:10.00 SS CYGNI ACIS-S HETG 50.00
===================================================================================
Proposal Number: 01300514
Proposal Title: A STUDY OF THE CLASSIC BOUNDARY LAYER IN U GEM AT QUIESCENCE
PI: PAULA SZKODY
Subject Category: WD BINARIES AND CV
Abstract: We will use the HETG to observe the 0.4-10 keV spectrum of the
simplest, most straightforward, bright disk system at quiescence (the
prototypical dwarf nova U Gem) in order to obtain good diagnostics for the
boundary layer plasma as it undergoes transition from an 8 keV low density region
to the atmosphere of a 30,000K white dwarf. The use of the Fe lines at 6.4-6.7
keV together with the emission lines in the 0.5-2 keV region will provide
information on the correct temperature and density structure, the
photoionization/collisional processes and the abundances of the material
transferred from the secondary star. In addition, the velocity broadening in the
lines will give insight into the rotation and location of the gas.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
07:55:05.30 +22:00:05.70 U GEM ACIS-S HETG 100.00
===================================================================================
Proposal Number: 01300579
Proposal Title: BROAD-BAND HIGH RESOLUTION SPECTROSCOPY OF SS CYGNI IN OUTBURST
PI: CHRISTOPHER MAUCHE
Subject Category: WD BINARIES AND CV
Abstract: We propose to observe the dwarf nova SS Cygni in outburst with the AXAF
LETGS and HETGS to (1) measure the differential emission measure of the X-ray
emitting plasma over three decades in temperature (from ~ 3e5 to 3e8 K), (2)
measure the abundances and density of the plasma responsible for the hard
component of the spectrum, (3) determine or constrain the physical conditions and
emission mechanism(s) responsible for the soft component of the spectrum, and (4)
measure the spectrum of the soft X-ray oscillations, thereby diagnosing their
cause. Finally, assisted by simultaneous RXTE observations, we will measure the
line and continuum spectrum reflected from the surface of the white dwarf and
accretion disk.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
21:42:42.30 +43:35:08.00 SS CYG ACIS-S HETG 35.00
21:42:42.30 +43:35:08.00 SS CYG ACIS-S HETG 65.00
===================================================================================
Proposal Number: 01300628
Proposal Title: HETG SPECTROSCOPY OF BRIGHT INTERMEDAITE POLARS
PI: KOJI MUKAI
Subject Category: WD BINARIES AND CV
Abstract: Intermediate Polars (IPs) are the hard X-ray brightest subclass of
magnetic Cataclysmic Variables. Previous X-ray observations, notably those with
ASCA, have established the complex nature of their spectra: multi-temperature
plasma and complex absorber are both required. Moreover, one recent study
suggests that the Fe lines are Compton broadened in at least some systems. We
propose HETG observations of 2 bright IPs, V1223 Sgr and AO Psc, to search for
K-alpha lines of Ne, Mg, Si, S, Ar and Ca; to measure the physical widths of any
lines we do detect; to search for a direct evidence for an ionized absorber; and
to obtain an improved characterization of the spin modulation.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
18:55:02.30 -31:09:49.30 V1223 SGR ACIS-S HETG 50.00
===================================================================================
Proposal Number: 01300669
Proposal Title: STUDYING THE OLD NOVA SHELL OF GK PERSEI IN X-RAYS
PI: SOLEN BALMAN
Subject Category: WD BINARIES AND CV
Abstract: We propose an AXAF ACIS-I observation to study the detailed morphology
and the spectrum of the nova shell of GK Persei 1901 SIMULTANEOUSLY in X-ray
wavelengths. The shell was recently detected with the ROSAT HRI, thus no spectral
information was derived from the data. We plan to exploit the spatial and
spectral capabilities of the ACIS-I detector in order to study the spectrum of
the source in comparison to other wavelengths. We expect that such an observation
will have great implications on our understanding of the classical novae
evolution , outburst mechanisms together with the interaction of the nova shells
with their environments of interstellar or circumstellar origin and physics of
strong shock formation.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
03:31:12.00 +43:54:17.00 GK PERSEI ACIS-S NONE 100.00
===================================================================================
Proposal Number: 01300820
Proposal Title: THE X-RAY SPATIAL AND SPECTRAL STRUCTURE OF R AQUARII
PI: EDWIN KELLOGG
Subject Category: WD BINARIES AND CV
Abstract: The nearby (~200pc) R Aqr symbiotic system, a known EXOSAT/ROSAT
source, is a well-known prototype for non-relativistic astrophysical jets, giving
a unique AXAF opportunity to resolve spatially an x-ray system with mass infall
onto a compact hot object with an accretion disk and jet. The R Aqr jet has been
extensively observed in the UV, optical, and radio by Hollis et al. Previous
ROSAT HRI observations could not resolve the jet, but, based on HST UV and VLA
radio data, shock model temperatures indicate that an x-ray jet is about the same
size as the UV jet. This AXAF observation will yield ~4000 counts, enough for a
high quality image. Using the ACIS BI spectrum, optically thin hot gas lines will
be evident; time variations and source modeling will also be pursued.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
23:43:49.45 -15:17:04.19 R AQUARII ACIS-S NONE 26.00
===================================================================================
Proposal Number: 01300860
Proposal Title: MULTIWAVELENGTH TOO OBSERVATIONS OF BRIGHT NOVAE IN OUTBURST
PI: SUMNER STARRFIELD
Subject Category: WD BINARIES AND CV
Abstract: We propose to obtain spectrophotometry with the ACIS-FI instrument,
plus contemporaneous ground based optical and infrared spectra, of bright novae
in outburst. Previous studies with X-ray satellites have shown that they are the
best tool for studying the hot phases of the nova outburst. In these
observations, both soft and hard emission components were found. Observations of
the soft component will provide a unique opportunity to study the composition of
the ejecta, the lifetime of the outburst, and the evolution of the white dwarf.
The hard component is, as yet, unexplained and further observations are urgently
needed to understand its cause and behavior which will improve our understanding
of the evolution of the ejecta. We will obtain observations of both components
when possible.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
10:44:48.37 -52:25:30.61 V382 Velorum 1999 HRC-S LETG 25.00
10:44:48.37 -52:25:30.61 V382 Velorum 1999 ACIS-I NONE 20.00
10:44:48.37 -52:25:30.61 V382Velorum1999 ACIS-I NONE 5.00
10:44:48.37 -52:25:30.61 V382Velorum1999 ACIS-I NONE 10.00
19:23:05.28 +04:57:21.06 V1494AQL ACIS-I NONE 5.00
19:23:05.28 +04:57:21.60 V1494 Aql HRC-S LETG 8.00
19:23:05.28 +04:57:21.60 V1494 Aql HRC-S LETG 17.00
19:23:05.28 +04:57:21.60 V1494 Aql ACIS-I NONE 5.00
19:23:05.28 +04:57:21.60 V1494 Aql ACIS-I NONE 5.00
===================================================================================
Proposal Number: 01300889
Proposal Title: X-RAY CONSTRAINTS ON THE BINARY STAR POPULATIONS IN OMEGA
CENTAURI
PI: Adrienne Cool
Subject Category: WD BINARIES AND CV
Abstract: We propose to obtain a 70 ksec ACIS observation of the globular cluster
Omega Cen. A high rate of stellar interactions and large core make Omega Cen a
prime target for the study of low-luminosity cluster X-ray sources. We will (1)
measure the luminosity function and radial distribution of cataclysmic variables
down to Lx = 2e30 erg/s; (2) determine the frequency of RS CVn X-ray binaries in
a globular cluster for the first time; (3) provide the accurate positions needed
for identifying optical counterparts in crowded fields; and (4) enable detailed
comparisons between clusters with different dynamical properties. An order of
magnitude more sensitive than previous work, this study will provide new
constraints on primordial and capture binaries that are vital to cluster
dynamical evolution.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
13:26:45.90 -47:28:37.00 NGC 5139 ACIS-I NONE 25.00
===================================================================================
Proposal Number: 01300897
Proposal Title: X-RAYING COMPACT BINARIES IN THE EXTREME GLOBULAR CLUSTER,
TERZAN 5
PI: JONATHAN GRINDLAY
Subject Category: WD BINARIES AND CV
Abstract: The extreme stellar density and yet relatively large core of the
massive globular cluster Terzan 5 make it the ideal target for the study of the
formation of compact objects and binaries in dense stellar systems. We propose a
deep ACIS-I exposure to study both its known LMXB and bright (eclipsing) MSP and
to measure its underlying distribution of LMXBs, CVs and MSPs. When combined with
our upcoming HST/NICMOS survey of Ter5 for emission line object identifications,
this AXAF observation will set significant constraints on the origin of cluster
binaries and neutron stars, the evolutionary links between LMXBs and MSPs, and
the cluster gravitational potential.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
17:48:04.90 -24:46:44.90 TERZAN 5 ACIS-I NONE 5.00
17:48:04.90 -24:46:44.90 TERZAN 5 ACIS-I NONE 45.00
===================================================================================
Proposal Number: 01300004
Proposal Title: OBSERVATIONS OF SUPER SOFT X-RAY SOURCES WITH LETGS
PI: PETER PREDEHL
Subject Category: WD BINARIES AND CV
Abstract: The standard model of supersoft X-ray sources (SSS) adopts a WD burning
accreted H stably on its surface. These LETG observations of both the prototype
SSS CAL83 and the brightest ROSAT SSS (2c/s) will test this model by resolving
for the first time the predicted absorption edges of heavy elements (mainly C+O)
in the WD atmosphere. ASCA/SAX observations give first hints for edges, but have
too poor sensitivity below 0.5 keV. Also, the XMM grating can only be used for RX
J0925.7-4758, a particularly hard SSS in the galactic plane. RX J0019.8+2156 is
the brightest galactic SSS with HRC-S-LETG, giving 0.2 cts/s, kT=35 eV bbdy,
logNH=20.6-20.8.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
00:19:50.00 +21:56:54.00 RX J0019.8+2156 HRC-S LETG 50.00
===================================================================================
Proposal Number: 01300005
Proposal Title: X-RAY SPECTROSCOPY OF THE SOFT INTERMEDIATE POLAR RE0751+14
PI: PETER PREDEHL
Subject Category: WD BINARIES AND CV
Abstract: RE0751+14 is the brightest of a new class of intermediate polars
discovered by ROSAT. Its soft X-ray spectrum is dominated by a blackbody-like
component with a temperature of about 50 eV, reminiscent of that seen in the
strongly magnetic polars. In analogy the soft component probably originates from
an accretion-heated surface region around the white dwarfs magnetic pole(s). We
propose to do high resolution X-ray spectroscopy of RE0751+14 to investigate in
detail the soft spectral component. Resolving spectral features will provide very
valuable information on the emission mechanism and the white dwarf atmosphere. It
will be vital to find the physical parameters which rule the production of the
soft X-ray component in soft intermediate polars.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
07:51:17.30 +14:44:23.00 RE 0751+14 HRC-S LETG 50.00
===================================================================================
Proposal Number: 01300009
Proposal Title: OBSERVATIONS OF SUPER SOFT X-RAY SOURCES WITH LETGS
PI: ALBERT BRINKMAN
Subject Category: WD BINARIES AND CV
Abstract: The standard model of supersoft X-ray sources (SSS) adopts a WD burning
accreted H stably on its surface. These LETG observations of both the prototype
SSS CAL83 and the brightest ROSAT SSS (2 c/s) will test this model by resolving
for the first time the predicted absorption edges of heavy elements (mainly C+O)
in the WD atmosphere. ASCA/SAX observations give first hints for edges, but have
too poor sensitivity below 0.5 keV. Also, the XMM grating can only be used for RX
J0925.7-4758, a particularly hard SSS in the galactic plane. CAL83 is a bright
LMC source with a predicted 0.09 cts/s, kT=35 eV bbdy, logNH=20.6-20.8).
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
05:43:33.50 -68:22:23.00 CAL 83 HRC-S LETG 50.00
===================================================================================
Proposal Number: 01300075
Proposal Title: DIFFUSE X-RAY EMISSION IN GLOBULARS: HOT GAS VS. NON-THERMAL
EMISSION IN 47 TUC
PI: STEPHEN MURRAY
Subject Category: WD BINARIES AND CV
Abstract: We propose a deep ACIS-S observation of 47 Tuc to confirm and map our
ROSAT discovery of diffuse emission from a probable bow shock and possible
non-thermal emission from the large population of millisecond pulsars. The bow
shock emission will be mapped out to 5-10arcmin from the peak diffuse emission
and measure the proper motion of the cluster in the Galaxy. The spectral
distribution will constrain both the mass loss of cluster stars and the
temperature-density of the hot gas in the galactic halo. The possible IC emission
from low energy CR electrons accelerated in the bow shock will constrain the MSP
population and particle production in the cluster, while the spectra of point
sources will complement and extend our deep HRC-I survey for CVs and dim x-ray
sources in this key cluster.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
00:24:05.83 -72:04:51.24 47 TUC ACIS-I NONE 1.00
00:24:05.83 -72:04:51.24 47 TUC ACIS-I NONE 4.00
00:24:05.83 -72:04:51.24 47 TUC ACIS-I NONE 4.00
00:24:05.83 -72:04:51.24 47 TUC ACIS-I NONE 32.50
00:24:05.83 -72:04:51.24 47 TUC ACIS-I NONE 32.50
===================================================================================
Proposal Number: 01300129
Proposal Title: NATURE AND ORIGIN OF CATACLYSMIC VARIABLES AND DIM X-RAY SOURCES
IN GLOBULAR CLUSTERS
PI: STEPHEN MURRAY
Subject Category: WD BINARIES AND CV
Abstract: We propose a deep initial study of the CV population and dim x-ray
sources in two globular clusters, NGC 6397 and 47 Tuc. Both clusters have
extensive dim (Lx ~ 10^31-33 erg/s) x-ray source populations which our ROSAT/HST
studies have shown are likely dominated by CVs although the brightest sources in
47 Tuc may also include quiescent LMXBs. The HRC-I (47Tuc) and ACIS-S (NGC 6397)
images will allow the luminosity function, variability, and source
identifications (with planned HST followup) to be measured and constraints on the
origin of cluster WDs and NSs as well as compact binaries in these two
contrasting globulars (differing in metallicity, halo vs. disk, and mass) to be
derived. A complementary ACIS-S study of 47Tuc will measure spectra of both dim
sources and the diffuse emission.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
17:40:42.20 -53:40:23.70 NGC 6397 ACIS-I NONE 49.00
===================================================================================
Proposal Number: 01300130
Proposal Title: SUPER-SOFT X-RAY SOURCES
PI: STEPHEN MURRAY
Subject Category: WD BINARIES AND CV
Abstract: The nature of a large subset of luminous supersoft X-ray sources (SSSs)
has not yet been established. Although they are thought to be white dwarfs
steadily burning accreted matter, there is no definitive evidence that this
picture is correct: in particular we do not have direct evidence that any of the
systems contain an accreting white dwarf. The observations we propose will
provide good spectral information for all of the SSSs that are candidates for the
nuclear-burning white dwarf model. We will be able to extract values of the
temperature, luminosity and N_H, and to see evidence of absorption edges that may
be associated with the white dwarf's atmosphere.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
00:19:50.00 +21:56:54.00 RX J0019.8+2156 ACIS-S NONE 1.00
00:37:19.80 -72:14:13.00 1E 0035.4-7230 ACIS-S NONE 5.70
00:58:37.00 -71:35:48.00 1E 0056.8-7154 ACIS-S NONE 13.30
04:39:49.60 -68:09:02.00 RX J0439.8-6809 ACIS-S NONE 8.00
05:43:33.50 -68:22:33.00 CAL 83 ACIS-S NONE 2.00
09:25:46.20 -47:58:17.00 RX J0925.7-4758 ACIS-S NONE 1.00
16:01:40.90 +66:48:10.00 AG DRA ACIS-S NONE 20.00
===================================================================================
Proposal Number: 01308004
Proposal Title: BZ CAM - A TRANSIENT SUPERSOFT X-RAY SOURCE?
PI: ROSANNE DI STEFANO
Subject Category: WD BINARIES AND CV
Abstract: BZ Cam is a binary with a 221 min. period. It contains an accreting
white dwarf and a 0.3-0.4 solar mass main-sequence donor. BZ Cam belongs to the
group of variables called VY Scl stars. Most of the time it spends at V=12.7 mag,
but during low states it has V=14.3 mag. BZ Cam is surrounded by a faint emission
nebula (AA 181, 373). Photoionization by a canonical cataclysmic variable cannot
account for the nebular excitation (emission line ratios). The proposed ACIS-S
observation will test the hypothesis that BZ Cam, like V751 Cyg (A&A 343, 183)
and the canonical supersoft source (SSS) RX J0513.9-6951, emits luminous
supersoft X-rays during its optical low-state. If supersoft X-rays could be
detected, it would have 2 major implications: (1) Discovery of new object class:
VY Scl stars = tra
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
06:29:34.00 +72:04:37.60 Mispointing ACIS-S NONE 5.00
===================================================================================
Proposal Number: 01308010
Proposal Title: BZ CAM - A TRANSIENT SUPERSOFT X-RAY SOURCE?
PI: ROSANNE DI STEFANO
Subject Category: WD BINARIES AND CV
Abstract: BZ Cam is a binary with a 221 min. period. It contains an accreting
white dwarf and a 0.3-0.4 solar mass main-sequence donor. BZ Cam belongs to the
group of variables called VY Scl stars. Most of the time it spends at V=12.3-12.7
mag, but during low states it has V=14.3 mag. BZ Cam is surrounded by a faint
emission nebula (AA 181, 373). Photoionization by a canonical cataclysmic
variable cannot account for the nebular excitation (emission line ratios). The
proposed ACIS-S observation will test the hypothesis that BZ Cam, like V751 Cyg
(A&A 343, 183) and the canonical supersoft source (SSS) RX J0513.9-6951, emits
luminous supersoft X-rays during its optical low-state. If supersoft X-rays could
be detected, it would have 2 major implications: (1) Discovery of new object
class: VY Scl stars
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
06:29:34.00 +71:04:38.00 BZ CAM ACIS-S NONE 5.00
===================================================================================
Proposal Number: 01308011
Proposal Title: CHANDRA HETG SPECTROSCOPY OF EX HYDRAE
PI: STEVE HOWELL
Subject Category: WD BINARIES AND CV
Abstract: EX Hya is an eclipsing intermediate polar-type CV with strong H- and
He-like K alpha emission lines of Mg, Si, S, Ar, and Fe emission lines of Ne
VII-VIII and Fe XVIII-XXIII in the EUV spectrum. The density of the emitting
plasma of EX Hya is ~ 10^13 to 10^15 cm^-3, more than an order of magnitude
greater than that of the corona of cool stars. We propose a 60 ks Chandra HETG
spectrum of EX Hya to: (1) constrain the run of density with temperature (thereby
constraining models of the accretion column), (2) measure the amount of fluor-
escence from the irradiated surface of the WD, (3) measure elemental abundances
(controversial from the ASCA spectrum), and (4) spectroscopically measure the
density of the emitting plasma (via line ratios of He-like O VII, Ne IX, Mg XI,
Si XIII, S XV, Ar XVII
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
12:52:24.40 -29:14:56.00 EX HYA ACIS-S HETG 60.00
===================================================================================
Proposal Number: 01308030
Proposal Title: THE NATURE OF CLASSICAL SYMBIOTIC OUTBURSTS
PI: PHIL CHARLES
Subject Category: WD BINARIES AND CV
Abstract: Symbiotic stars may be the progenitors of the cosmologically important
Type Ia SNe. The high accretion rate onto the white dwarfs (WDs) in these
binaries allows for steady, rather than explosive burning as in classical novae.
The accreted material can therefore remain on the WD, driving its mass closer to
the Chandrasekhar limit, rather than being blown off in a nova. OR CAN IT?
Classical symbiotics experience outbursts typically every 10 - 20 years, and
these events are not well-understood. After the 1985 outburst of the class
prototype, Z Andromedae (which is also a 28-minute pulsar), it appeared that a
shell of material had been ejected from the WD. This object has recently outburst
again. An X-ray observation within roughly one month will provide v, T, and
density diagnostics deep wit
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
23:33:40.00 +48:49:06.00 Z ANDROMEDAE ACIS-S HETG 20.00
***********************************************************************************
BH AND NS BINARIES
--------------------------------------------------
===================================================================================
Proposal Number: 01400221
Proposal Title: THE BINARY MS-PULSAR PSR J0218+4232 AND ITS PROBABLE SYNCHROTRON
NEBULA
PI: Lucien Kuiper
Subject Category: BH AND NS BINARIES
Abstract: In a recent 100 ks ROSAT HRI observation of the binary ms-pulsar PSR
J0218+4232 we detected a lightcurve with two narrow pulses; the measured width of
the main pulse (350 microsec) is compatible with the scatter in the ROSAT clock.
About 60% of the emission is unpulsed and can be explained by emission from a
compact nebula with diameter ~14'', compatible with available radio data. Only
AXAF's HRC-I can disentangle the spatial emission, as well as resolve the narrow
structures in the lightcurve; a 75 ks observation suffices. We further propose a
spectral study of this ms-pulsar and its probable synchrotron nebula with AXAF's
ACIS-I detector (100 ks) in order to investigate the underlying production
processes.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
02:18:06.30 +42:32:17.40 PSR J0218+4232 HRC-I NONE 75.00
02:18:06.30 +42:32:17.40 PSR J0218+4232 HRC-S NONE 75.00
===================================================================================
Proposal Number: 01400342
Proposal Title: SPECTRAL VARIABILITY IN A SUPERGIANT X-RAY BINARY
PI: BRAM BOROSON
Subject Category: BH AND NS BINARIES
Abstract: We will observe the supergiant X-ray binary 4U 1700-37 for 40-50% of
its orbit, from its normal bright state through the pre-eclipse absorption state,
and into eclipse. We will map the accreting wind from the variable absorption
column and absorption edges. We expect to see a rich line spectrum including
fluorescent and recombination lines. We will investigate the response of these
lines and the absorption to X-ray flares. By mapping the gas jet from the
companion and the stellar wind, we can determine the accretion rate from the both
the spherical wind and from Roche lobe overflow.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
17:03:56.59 -37:50:38.90 4U 1700-37 ACIS-S HETG 40.00
===================================================================================
Proposal Number: 01400425
Proposal Title: AN X-RAY IMAGING SURVEY OF JETS FROM X-RAY BINARIES : ENERGETICS
OF OUTFLOWS FROM NEUTRON STARS AND BLACK HOLES
PI: ROBERT FENDER
Subject Category: BH AND NS BINARIES
Abstract: We propose to use ACIS-I to image the fields of the eight X-ray
binaries with strong evidence for relativistic jets. In this way we will
investigate the energetics of such outflows by observing the energy they deposit
in the ISM through interactions with the ambient medium. This will provide an
estimate of the power of such outflows from neutron stars and black holes which
is independent of the assumptions associated with estimates based on light curves
and radio observations, as well as shedding light on their local environments.
All the fields will be quasi-simultaneously mapped at a comparable resolution at
radio wavelengths to examine the relation between synchrotron-emitting electrons
and high energy emission.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
17:43:54.85 -29:44:42.76 1E 1740.7-2942 ACIS-I NONE 10.00
19:11:49.50 +04:58:58.00 SS 433 (EAST JET) ACIS-S NONE 10.00
===================================================================================
Proposal Number: 01400453
Proposal Title: ACIS-HETG OBSERVATIONS OF GRS1915+105: A MICRO BAL-QUASAR ?
PI: JULIA LEE
Subject Category: BH AND NS BINARIES
Abstract: Previous ASCA observations of the X-ray transient GRS1915+105 have
revealed prominent absorption lines from highly ionized iron, possibly due to a
photoionized wind from the putative black hole accretion disk. We propose to
perform high resolution spectroscopy of the iron line complex via a 30ksec
ACIS-S/HETG observation. The line of sight velocity and velocity dispersion of
the absorbing matter will be accurately measured, and the P-Cygni profiles
(confirming the presence of a wind) will be sought. By aligning the ACIS-S with
the axis of the known jet, we will be sensitive to any multiple-arcminute scale
structure in this jet. We also aim to propose for RXTE observations which will
compliment this study by constraining the geometry/structure of the disk/corona
system.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
19:15:11.40 +10:56:44.00 GRS 1915+105 ACIS-S HETG 30.00
===================================================================================
Proposal Number: 01400467
Proposal Title: THE FAINTEST 'FIELD' LOW-MASS X-RAY BINARIES
PI: MICHIEL VAN DER KLIS
Subject Category: BH AND NS BINARIES
Abstract: There exists a group of persistently faint galactic X-ray sources that,
based on characteristics such as location in the galaxy, high Lx/Lopt,
association with X-ray bursts, absence of X-ray pulsations and similar
characteristics are thought to be low-mass X-ray binaries but about which very
little is known. These objects have low Lx and most have not been optically
identified. We propose to observe a sample of these sources with ACIS in modes
and with exposure times tailored to obtain an arcsecond position, and to measure
a good X-ray spectrum and a good power spectrum. This will extend our knowledge
about the physics of accretion onto compact objects towards lower accretion rates
than previously accessible.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
17:12:24.90 -40:50:34.60 1708-408 ACIS-S NONE 1.00
17:14:19.40 -34:02:43.00 1711-339 ACIS-S NONE 1.00
17:38:17.00 -26:59:55.20 1735-269 ACIS-S NONE 1.00
17:38:17.00 -26:59:55.20 1735-269 ACIS-S NONE 1.00
17:39:30.40 -29:42:11.10 1736-297 ACIS-S NONE 1.00
17:39:30.40 -29:42:11.10 1736-297 ACIS-S NONE 12.00
17:49:48.50 -33:12:15.40 1746-331 ACIS-S NONE 1.00
17:49:48.50 -33:12:15.40 1746-331 ACIS-S NONE 3.00
17:50:03.90 -32:26:22.50 1746.7-3224 ACIS-S NONE 7.00
18:15:16.50 -12:05:08.70 1812-12 ACIS-S NONE 1.00
===================================================================================
Proposal Number: 01400227
Proposal Title: HIGH RESOLUTION SPECTROSCOPY OF THE ACCRETION DISK CORONA SOURCE
4U 1822-37
PI: STEVEN KAHN
Subject Category: BH AND NS BINARIES
Abstract: We propose to observe 4U 1822-37 with the ACIS-S-HETG. 4U 1822-37 is
the only observable accretion disk corona source in the original class of these
objects. Past observations have only detected a few low equivalent width lines
rather than the dense line emission expected from models of ADCs. Attempts to fit
these data have been unsuccessful leaving unanswered many questions regarding the
nature of the compact and companion stars and the mechanism of mass transfer and
coronal formation. With the high resolution of the HETG gratings we will be able
to finally resolve any existing line structure and use these diagnostics to
constrain models of this peculiar form of LMXB.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
18:25:46.70 -37:06:18.90 4U 1822-37 ACIS-S HETG 40.00
===================================================================================
Proposal Number: 01400560
Proposal Title: THE LUMINOUS BURSTING X-RAY SOURCES IN GLOBULAR CLUSTER CORES:
LOCATION, LOCATION, AND LOCATION
PI: Bruce Margon
Subject Category: BH AND NS BINARIES
Abstract: The highly luminous bursting X-ray sources in the cores of globular
clusters are some of the most exotic stellar systems known. Recently HST imaging
has led to optical candidates for many of these central cluster sources, but
these candidates have a diverse range of properties. Even for the most accurate
(3") X-ray positions extant pre-AXAF, there are sometimes hundreds of candidate
counterparts permitted on positional grounds alone; evidence is thus quite
inconclusive, and some of the current candidates may be incorrect. We propose to
obtain highly accurate AXAF positions for most of the known sources, reducing the
number of candidates by up to 100X, using an instrument configuration that will
also provide a homogeneous set of high resolution spectra for much of the
sample.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
05:14:06.60 -40:02:36.80 NGC 1851 HRC-S LETG 12.00
17:27:33.20 -30:48:07.80 TERZAN 2 HRC-S LETG 7.70
17:33:24.00 -33:23:16.40 LILLER 1 HRC-I NONE 15.40
===================================================================================
Proposal Number: 01400360
Proposal Title: SOFT X-RAY DIAGNOSTICS OF A POSSIBLE ADC IN X2127+119
PI: NICHOLAS WHITE
Subject Category: BH AND NS BINARIES
Abstract: X2127+119 exhibits dips with a period of 17.1 hours. Its accretion disk
may possess an ionized corona (ADC), though the apparent lack of reprocessing of
a bright type I burst disputes this possibility. One diagnostic of ADC conditions
is strong discrete emission, whose analysis sheds light upon the location of and
temperature and ionization level in the reprocessing gas. To date this system has
never been observed spectroscopically with good energy resolution or at soft
X-ray energies (where spectral features abound). We propose two observations of
X2127+119: one using the ACIS-S-LETG and one using the ACIS-S-HETG. We show that
X2127+119 is sufficiently bright to produce good spectra and that such spectra
will likely include numerous strong soft emission features.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
21:29:58.30 +12:10:09.00 X2127+119 ACIS-S HETG 20.00
===================================================================================
Proposal Number: 01400607
Proposal Title: BLACK HOLE EVENT HORIZONS AND ADVECTION-DOMINATED ACCRETION
PI: JEFFREY MCCLINTOCK
Subject Category: BH AND NS BINARIES
Abstract: We propose to establish the existence of black-hole event horizons by
comparing accreting black holes to accreting neutron stars. Such a comparison is
feasible because black holes and neutron stars are both present in similar
environments in X-ray novae. Recently, a very successful model (ADAF model) has
been applied to X-ray novae. It predicts that variations in luminosity between
the quiescent state and the outburst state for X-ray novae that contain black
holes are expected to be > 100 times larger than for X-ray novae that contain
neutron stars. Preliminary results from ROSAT and ASCA support this prediction,
as expected if black holes have event horizons and neutron stars do not. The
proposed observations with AXAF can firmly establish whether black holes have
event horizons.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
04:21:42.80 +32:54:27.00 GRO J0422+32 ACIS-I NONE 20.00
15:47:08.60 -47:40:10.00 4U 1543-47 ACIS-I NONE 10.00
===================================================================================
Proposal Number: 01400660
Proposal Title: AXAF OBSERVATIONS OF THE RAPID BURSTER IN OUTBURST
PI: WALTER LEWIN
Subject Category: BH AND NS BINARIES
Abstract: The Rapid Burster (RB) is a recurrent transient low-mass X-ray binary
with type II burst phenomenology that makes it unique in the Galaxy. We propose
to obtain high-resolution grating spectra (ACIS-S + HETG) of the RB in outburst.
In one 30 ksec observation we will collect ~150,000 photons from type II bursts
and at least ~90,000 photons from the persistent emission. Spectral features in
the type II bursts and the persistent emission may illuminate the physics of the
accretion process that drives these bursts, perhaps allowing us to finally
understand some of the physics behind this enigmatic object.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
17:33:24.60 -33:23:19.80 RAPID BURSTER ACIS-S HETG 30.00
===================================================================================
Proposal Number: 01400700
Proposal Title: AXAF OBSERVATIONS OF A BRIGHT BLACK HOLE X-RAY BINARY IN
OUTBURST
PI: WALTER LEWIN
Subject Category: BH AND NS BINARIES
Abstract: We propose to study the X-ray spectra of black-hole (candidate) X-ray
binaries (BHXBs) in outburst. We will follow the outburst throughout its
evolution across all wavelength bands, and will select certain periods for X-ray
spectral analysis with AXAF. High-resolution X-ray spectra of the BHXBs will
likely exhibit emission lines and absorption edges characteristic of the
accretion disk geometry, temperatures, and abundances. We expect that they will
show the general-relativistic effects of the extreme gravitational environment
near the black hole. When possible, we will make (near) simultaneous radio, IR,
optical, X-ray timing (RXTE), and gamma-ray (CGRO-BATSE) observations. Our team
has extensive expertise in all aspects of the proposed research.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
15:50:58.90 -56:28:35.30 XTE J1550-564 (0.05 ACIS-S HETG 6.00
15:50:58.90 -56:28:35.30 XTE J1550-564 (OUTBU ACIS-S HETG 2.00
15:50:58.90 -56:28:35.30 XTE J1550-564 (OUTBU ACIS-S HETG 2.00
15:50:58.90 -56:28:35.30 XTE J1550-564 (OUTBU ACIS-S NONE 2.00
15:50:58.90 -56:28:35.30 XTE J1550-564 (OUTBU ACIS-S HETG 1.20
15:50:58.90 -56:28:35.30 XTE J1550-564 (OUTBU ACIS-S HETG 1.20
15:50:58.90 -56:28:35.30 XTE J1550-564 (OUTBU ACIS-S NONE 1.20
===================================================================================
Proposal Number: 01400713
Proposal Title: HETGS STUDY OF PERSISTENT AND BURST EMISSION FROM TWO LUMINOUS
BURSTERS
PI: Jean Swank
Subject Category: BH AND NS BINARIES
Abstract: Serpens X-1 and 4U 1735-44 are two bursting low-mass X-ray binaries
which have shown confirmed Fe K line emission and less certain evidence of low
energy line emission. Reported variations in Fe K line, energy, and width suggest
that the inner disk region is sometimes the dominant formation region for these
relatively luminous persistent sources at low inclination. Quasiperiodic
oscillations at high frequencies also arise in the inner disk region and
simultaneous RXTE data would correlate temporal behavior, the continuum and
lines. For each source we propose an 80 ksec HETG/ACIS observation likely to
include at least a few bursts. Simultaneous HETG and RXTE burst spectra would
test predicted divergence from black body models and better constrain neutron
star parameters.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
18:39:57.00 +05:02:06.00 SERPENS X-1 ACIS-S HETG 80.00
===================================================================================
Proposal Number: 01400738
Proposal Title: RESOLVING LOW ENERGY LINES FROM LMXRB
PI: LORELLA ANGELINI
Subject Category: BH AND NS BINARIES
Abstract: ASCA observations of the LMXRB X0918-54,X1543-62 and X0614+09 reveal
strong emission lines in the 0.5-1 keV band.The emission is consistent with
Oxygen and Iron L,but major uncertanties remain in establishing the line emission
mechanism.The recombination continuum,a signature of photoinonization,is missing
or at lower level in all systems. A collisionial plasma better reproduces the
spectrum. Scattering and 3-body recombinations are other possible mechanism that
can lower the recombination. Observations with the AXAF HETG of the 3 objects can
differentiate line emission with an unprecedented resolving power.This capability
will pin-down the underline mechanism responsible for the line emission, and
define abundances to constrain the system evolution.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
09:20:26.70 -55:12:23.00 X0918-54 ACIS-S HETG 30.00
15:47:54.70 -62:34:05.00 X1543-62 ACIS-S HETG 30.00
===================================================================================
Proposal Number: 01400776
Proposal Title: HIGH RESOLUTION X-RAY SPECTROSCOPY OF COMPACT BINARIES
PI: SAEQA VRTILEK
Subject Category: BH AND NS BINARIES
Abstract: We propose to undertake a survey of Galactic X-ray binaries with the
ACIS-S+HETG. Owing to their proximity and brightness, X-ray binaries provide
otherwise unobtainable insight into the accretion process. We will: investigate
the physical conditions of the emitting gas using emission and recombination line
diagnostics to determine temperatures, densities, elemental abundances, and
ionization structure; test and improve models of X-ray line emission developed by
us over the past decade; and generate an atlas of spectra for use in comparative
studies of X-ray binaries. Insights gained from this work will be applicable to
irradiated, accreting plasmas which are present in regions of star formation,
interacting main-sequence binaries, active galactic nuclei and quasars.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
17:31:44.19 -16:57:41.18 4U 1728-16 ACIS-S HETG 20.00
17:38:58.26 -44:27:00.13 4U 1735-44 ACIS-S HETG 25.00
===================================================================================
Proposal Number: 01400874
Proposal Title: HIGH RESOLUTION SPECTROSCOPY OF THE STELLAR WIND IN CENTAURUS
X-3
PI: DUANE LIEDAHL
Subject Category: BH AND NS BINARIES
Abstract: The HMXB Cen X-3 is an eclipsing X-ray pulsar with an O-star companion.
It is the brightest X-ray source in its class. Spectroscopically, the
phase-averaged spectrum is a complex superposition of a bright continuum,
disk-reprocessed emission, and lines from a photoionized wind. The presence of an
accretion disk renders Cen X-3 overluminous relative to Bondi-Hoyle wind
accretion, resulting in a very high level of ionization in the wind. We propose
to observe Cen X-3 during eclipse with the HETG, which will allow us to
spectrally isolate the wind, focusing on its ionization, emission measure
distribution, and velocity structure. To accomplish this, we have developed an
X-ray spectral model that has been successfully applied to ASCA spectra of other
wind-dominated sources.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
11:21:15.20 -60:37:24.00 CEN X-3 ACIS-S HETG 40.00
===================================================================================
Proposal Number: 01400876
Proposal Title: HETG ZERO PHASE SPECTROSCOPY OF CIRCINUS X-1
PI: WILLIAM BRANDT
Subject Category: BH AND NS BINARIES
Abstract: We propose to make the first grating-resolution X-ray spectra of Cir
X-1 during one of its zero phase passages. Our ASCA analyses of Cir X-1 have
shown that its variable iron K features can be explained using a direct flux plus
scattered flux model, and HETG spectra will test our model. During zero phase
`dips' we expect line emission from an accretion disk corona (ADC), since we
predict predominantly ADC scattered emission below 5 keV. Line measurements will
constrain the ADC ionization parameter, temperature, thickness and motion. We
will also make the highest resolution iron K line/edge measurements and use them
to study obscuring matter. Our observation will not cause telemetry saturation,
and our dispersed spectra will not have serious photon pile up.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
15:20:41.00 -57:10:00.00 CIR X-1 ACIS-S HETG 15.00
15:20:41.00 -57:10:00.00 CIR X-1 ACIS-S HETG 30.00
===================================================================================
Proposal Number: 01400880
Proposal Title: THE PHYSICS OF X-RAY LINE EMISSION IN THE MICROQUASAR GRO
J1655-40
PI: DUANE LIEDAHL
Subject Category: BH AND NS BINARIES
Abstract: We propose a 40 ksec AXAF HETG TOO observation of the microquasar GRO
J1655-40 during outburst. The object shows both radio-loud and radio-quiet X-ray
outbursts, with relativistic jets accompanying the radio outbursts. Clear
evidence for intense emission near 1 keV and complex absorption in the Fe K band,
rare for a black hole candidate, have been observed with ASCA. The HETG can be
used to great advantage here, allowing us to extract detailed line diagnostics
and, through precise measurements of Doppler shifts, identify the possible
relationship of the line component to the jets. GRO J1655-40 represents a unique
opportunity to explore (``up close'') transient outburst accretion physics in a
black hole.
Grat- Exp.
R.A. Dec. (J2000) Target Name Det. ing Time
-----------------------------------------------------------------------------------
16:54:00.10 -39:50:44.90 GRO J1655-40 ACIS-S HETG 40.00
===================================================================================
Proposal Number: 01400882
Proposal Title: TEMPORAL EVOLUTION OF TRANSIENT TYPE I BURSTERS IN QUIESCENCE
PI: LARS BILDSTEN
Subject Category: BH AND NS BINARIES
Abstract: We propose TOO monitoring observations with ACIS-S-BI of Aql X-1, the
Rapid Burster, and one other type-I bursting transient in quiescence following an
outburst. Heat deposited in the deep neutron star (NS) crust during outburst
diffuses out on a timescale (about a year) which scales as the fourth power of
the NS radius. Temporal evolution will thus provide an observational handle on
the NS radius. Our data will