Hubble Space Telescope Daily Report #2866 – 7 May 2001

HUBBLE SPACE TELESCOPE

DAILY REPORT #2866

PERIOD COVERED: 0000Z (UTC) 05/04/01 – 0000Z (UTC) 05/07/01

Daily Status Report as of 127/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

1.1 Completed Two Sets of WF/PC-2 8604 (Stellar Populations Across the
Small Magellanic Cloud (SMC): History and Structure)

The WF/PC-2 was used to investigate the structure and evolutionary
history of the SMC by obtaining a series of 50 three-color snapshots of
selected SMC regions. With this polling of SMC field star properties, we
will produce color-magnitude diagrams in the U, V and I bands which will
reach V~23.5 in regions too crowded to be observed accurately from the
ground. The observations completed nominally.

1.2 Completed Thirty-one Sets of STIS/CCD 9248 (Probing the Large Scale
Structure: Cosmic Shear Observations)

The Space Telescope Imaging Spectrograph (CCD) was used to measure
the distortion of light bundles from distant galaxies that probe the
statistical properties of the intervening inhomogeneous {dark} matter
distribution. Its tidal gravitational field distorts the observable image
shapes thereby causing a coherent ellipticity pattern {Cosmic Shear}. As
described in 2.1 and HSTAR 8203, the acquisition for the twenty-third
iteration of this proposal defaulted to fine lock backup on one FGS only,
possibly affecting four observations. Otherwise, the observations
completed nominally.

1.3 Completed Two Sets of WF/PC-2 8702 (The Most Elusive Nuclei of LMC
Planetary Nebulae)

The WF/PC-2 was used to carry out a SNAPSHOT survey of the faintest
nuclei of planetary nebulae {PNe} in the LMC. This program will be a
crucial follow-on to a Cycle 8 SNAPSHOT of LMC Pne. In thisa case the plan
is to observe the faintest or most obscured nuclei to determine their
evolutionary state to an accuracy not possible in the Galaxy. These
faintest central stars are predicted to be among the most massive nuclei,
and owing to the typically advanced age of the surrounding nebulae, are the
most sensitive discriminants for validating the post-AGB evolution
timescales predicted by theory. The observations completed with no
reported problems.

1.4 Completed Four Sets of WF/PC-2 8581 (A Search For Low-Mass
Companions To Ultracool Dwarfs)

The WF/PC-2 was used to search for very low-mass {VLM} companions
to a complete sample of 120 late-M and L dwarfs, drawn mainly from the
2MASS and SDSS surveys. The primary goal is to determine the multiplicity
of M < 0.1 M_odot dwarfs. In particular, we aim to identify binary systems suitable for long-term astrometric monitoring and mass measurement, and systems with cool, sub-1000K companions. As described in 2.1 and HSTAR 8203, the acquisition for the third iteration of this proposal defaulted to fine lock backup on one FGS only, possibly affecting three observations. Otherwise, the proposal completed with no further reported problems.

1.5 Completed Eight Sets of WF/PC-2 8827 (Cycle 9 Supplemental Darks pt2/3)

The WF/PC-2 was used to obtain three dark frames every day to
provide data for monitoring and characterizing the evolution of hot
pixels. The proposal completed nominally.

1.6 Completed Two Sets of WF/PC-2/STIS/CCD/MA1 8867 (Gamma-Ray Bursts:
Discovering The Progenitors And Understanding The Explosion – Visits A0-R0)

The WF/PC-2 and the Space Telescope Imaging Spectrograph (CCD and
MA1) were used to observe a gamma-ray burster, GRB010222. Gamma-ray burst
astronomy, one of the most active and exciting frontiers in astrophysics,
is now entering a critical stage — with dramatic leaps in understanding of
these events, as well as new discoveries. Improvements in triggering and
positioning accuracy provided by the SAX and HETE-2 gamma-ray satellites
will allow entirely new classes of events to be studied. Given the recent
progress in this field, the proposers are now in a position to design
precision, broadband measurements that can provide quantitative information
on the as-yet unknown energy sources, the explosion geometry, and the
surrounding medium. In particular, the growing evidence of an intimate
connection between SNe and GRBs can be definitively tested. The proposal
completed with no reported problems.

1.7 Completed Six Sets of STIS/CCD 8664 (Structural Measurement of
Globular Clusters in M31 and NGC 5128: Stalking the Fundamental Plane)

The Space Telescope Imaging Spectrograph (CCD) was used to observe
in the snapshot mode to image a wide selection of individual globular
clusters in two other large galaxies {M31 and NGC 5128} for measurement of
their structural parameters {r_c, c, central surface brightness}. We will
use these to compute their binding energies and define the FP in these two
galaxies. Comparison with the Milky Way will then give us powerful new
information on just how “universal” the cluster formation process was in
the early protogalaxies. The observations completed with no reported problems.

1.8 Completed Two Sets of WF/PC-2/STIS/MA1 8686 (LINERs in Early-type
Galaxies: Ionized by the UV-upturn Population?)

The WF/PC-2 and the Space Telescope Imaging Spectrograph (MA1) were
used to investigate the presence of extended ionized gas with LINER spectra
in a large fraction {60-70%} of early-type galaxies. The observations
completed with no reported anomalies.

1.9 Completed Three Sets of STIS/CCD/MA1 8662 (A Snapshot Survey of the
Hot Interstellar Medium)

The Space Telescope Imaging Spectrograph (CCD And MA1) was used to
obtain snapshot STIS echelle observations of key tracers of hot
interstellar gas {C IV, N IV, and Si IV} for selected FUSE Team O VI survey
targets with known UV fluxes. By taking advantage of the snapshot
observing mode we will efficiently obtain a large number of spectra
suitable for the study of the highly ionized hot component of the
interstellar medium {ISM}. Our goals are to explore the physical
conditions in and distribution of such gas, as well as to explore the
nature of the interfaces between the hot ISM and the other interstellar gas
phases. The observations completed with no reported problems.

1.10 Completed Twelve Sets of WF/PC-2 9244 (POMS Test Proposal: WFII
Parallel Archive Proposal Continuation)

The WF/PC-2 was used to perform a generic target version of the
Archival Pure Parallel program. The program will be used to take parallel
images of random areas of the sky, following the recommendations of the
Parallels Working Group. The observations completed with no anomalous
activity.

1.11 Completed Three Sets of STIS/CCD 8865 (Bias Monitor-Part 2)

The Space Telescope Imaging Spectrograph (CCD) was used to monitor
the bias in the 1×1, 1×2, 2×1, and 2×2 bin settings at gain=1, and 1×1 at
gain = 4, to build up high-S/N superbiases and track the evolution of hot
columns. The proposal completed with no anomalous activity.

1.12 Completed Three Sets of STIS/CCD 8836 (Performance Monitor {Cycle 9})

The Space Telescope Imaging Spectrograph (CCD) was used to measure
the baseline performance and commandability of the CCD subsystem. Only
primary amplifier D was used. Bias and Flat Field
exposures were taken in order to measure read noise, CTE, and
gain. Numerous bias frames were taken to permit construction of
“superbias” frames in which the effects of read noise have been rendered
negligible. Full frame and binned observations were made, with binning
factors of 2 x 1, 1 x 2, 2 x 2, 4 x 1, and 4 x 2. Dark images were taken
in 2×2 binning mode; 1×1 binning darks are being taken in the nominal CCD
Dark Monitor. The exercise completed nominally.

1.13 Completed Two Sets of WF/PC-2 8815 (Cycle 9 Earth Flats)

The WF/PC-2 was used to monitor flatfield stability. This proposal
obtains sequences of Earth streak flats to construct high quality flat
fields for the WF/PC-2 filter set. These flat fields will allow mapping of
the OTA illumination pattern and will be used in conjunction with previous
internal and external flats to generate new pipeline superflats. The
proposal completed nominally.

1.14 Completed Ten Sets of STIS/CCD 8845 (Spectroscopic Flats C9)

The Space Telescope Imaging Spectrograph (CCD) was used to obtain
CCD flats in the spectroscopic mode. The observations completed with no
reported problems.

1.15 Completed WF/PC-2 8059 (POMS Test Proposal: Targeted Parallel
Archive Proposal)

The WF/PC-2 was used to observe the parallel opportunities
available in the neighborhood of bright galaxies are treated in a slightly
different way from the normal pure parallels. Local Group galaxies offer
the opportunity for a closer look at young stellar
populations. Narrow-band images in F656N can be used both to identify
young stars via their emission lines, and to map the gas distribution in
star-forming regions. The observations completed nominally.

1.16 Completed Three Sets of FGS/1 8731 (A High Angular Resolution
Survey of the Most Massive Stars in the SMC)

Fine Guidance Sensor #1 was used to conduct high angular resolution
observations of some of the SMC’s hottest and most luminous objects by
conducting a comprehensive survey of nearly every spectral type in the
upper portion of the HR diagram. Binary or multiple star systems will be
detected down to an unprecedented level, more than one order of magnitude
better than possible with WFPC2. The targets selected include a
representative list of normal Main Sequence O-stars and their evolved
descendents, namely supergiants, hypergiants, LBVs, and WRs, many of which
have been previously observed by HST’s spectrometers for purposes of
cosmological calibrations. The observations completed, and no problems
were reported.

1.17 Completed Two Sets of WF/PC-2 8602 (A Snapshot Survey of the Sites
of Recent, Nearby Supernovae)

The WF/PC-2 was used to conduct a snapshot survey in V and I of the
sites of the nearby SNe, which have precisely known positions, to obtain
high-resolution information on their local environment. The proposal
completed with no reported problems.

1.18 Completed Two Sets of STIS/CCD 8607 (Completing the Local AGN
Inventory: The AGN Content of Composite Nuclei)

The Space Telescope Imaging Spectrograph (CCD) was used to increase
the knowledge of the local space density of AGNs which is of fundamental
importance to a number of astrophysical problems. A significant fraction
of nearby galaxies have nuclei whose spectra are intermediate between those
of LINERs and nuclear starbursts. These “transition objects” may be
composite systems that contain both a central AGN and circumnuclear star
formation. We will test this hypothesis by obtaining spatially-resolved
optical spectra of a well-defined sample of 15 nearby transition nuclei
selected from the extensive ground-based survey of Ho, Filippenko, and
Sargent. The observations completed with no reported problems.

1.19 Completed STIS/CCD/MA1/MA2 8857 (MAMA Sensitivity and Focus
Monitor C9)

The Space Telescope Imaging Spectrograph (CCD, MA1 and MA2) was
used to monitor the sensitivity of each MAMA grating mode to detect any
change due to contamination or other causes. There were no problems.

1.20 Completed WF/PC-2 8677 (Extragalactic Novae: the Maximum Magnitude
– Rate of Decline Relation in NGC 4472)

The WF/PC-2 was used to accomplish two goals: {1} to provide the
first homogeneous observational constraints on theoretical models for novae
outbursts; and {2} to assess the reliability of novae as standard candles
by using WFPC2 to collect well sampled light curves for 20-50 novae in the
supergiant elliptical galaxy NGC 4472, the brightest galaxy within 30
Mpc. Both the length of the observing window and the temporal sampling of
the observations are specifically designed to ensure that the novae peak
magnitudes and decline rates are measured accurately. These data will be
used to construct the first `Maximum Magnitude versus Rate of Decline’
{MMRD} relation for a galaxy beyond the Local Group. This relation is not
only a potentially powerful standard candle, but its shape and dispersion
are directly linked to physical parameters which govern the physics of
novae outbursts such as the white dwarf mass, temperature and mass
accretion rate. The proposal completed with no reported problems.

1.21 Completed WF/PC-2 9163 (Kinematics Of Emission-Line Gas Disks In
Radio-Quiet Galaxies)

The WF/PC-2 was used to measure central black hole {BH} masses from
the rotation rate of the emission-line gas, and to determine the nature and
structure of the gas disks. Three galaxies with no radio jets and with
Halpha+[NII] emission have been identified, which have dust disks similar
to those commonly seen in our sample of radio-loud active galaxies. All
observations completed nominally.

1.22 Completed Two Sets of FGS/1 9240 (Astrometric Mass Determination
of an Extrasolar Planet Candidate)

Fine Guidance Sensor-1R was used to perform astrometric
observations that will allow a quick measure of the sky-plane motion of 55
Cancri, a G star with an Msin{i} = 0.9 MJ radial velocity companion with a
14 day period. By using 7 pairs of visits, where each visit within a pair
has the same parallax factor, we will be able to accurately determine the
stars’s proper motion. The reflex motion of the star, due to its orbit
about the star-companion barycenter, will manifest itself as a systematic
residual to the measured proper motion if the companion is sufficiently
massive. There were no reported problems.

1.23 Completed STIS/CCD/MA2 8569 (A New Survey for Low-Redshift Damped
Lyman-Alpha Lines in QSO MgII Systems)

The Space Telescope Imaging Spectrograph (CCD and MA2) was used to
support studies which have shown that most of the observable neutral gas
mass in the Universe resides in QSO damped LyAlpha {DLA} systems. However,
at low redshift, DLA can only be found by searching in the UV with HST. By
boot-strapping from the MgII statistics, we will be able to further improve
the determination of the low- redshift statistical properties of DLA {their
incidence and cosmological mass density} and open up new opportunities for
studies at low redshift. The observations completed nominally.

1.24 Completed WF/PC-2 8177 (Investigating Type Ia Supernovae and an
Accelerating Universe)

The WF/PC-2 was used to obtain rest frame U and B photometry for
four z~ 0.85 Supernova (SN) Ia. These observations will be coupled to
ground-based rest frame V photometry and spectra. These data, combined
with previous samples, will extend the D_L vs. z diagram for SN Ia to
z~0.85, and allow us to discriminate the redshift dependence of supernova
magnitudes in an accelerating Universe from that expected to result from
systematic effects such as age of the stellar population, chemical
evolution, a drift in the properties of dust, and weak gravitational
lensing. The proposal completed with no reported problems.

1.25 Completed Three Sets of WF/PC-2 8599 (A Census of Nuclear Star
Clusters in Late-Type Spiral Galaxies)

The WF/PC-2 was used to conduct an I-band snapshot survey of a
well-defined sample of nearby, face-on spiral galaxies of type Scd or
later. The proposal completed nominally.

1.26 Completed WF/PC-2 8820 (Wavelength Stability of Narrow Band and
Linear Ramp Filters)

The WF/PC-2 was used to verify the mapping of wavelength as a
function of CCD position on linear ramp filters and to check for changes in
central wavelengths of the narrow band filters. The proposal completed
nominally.

1.27 Completed WF/PC-2 8712 (The Wind Accretion Wake In A Detached
Binary System)

The WF/PC-2 was used to observe RW Hya {= HD 117970}, the only
known detached binary system, where direct observational evidence for wind
accretion onto a white dwarf is found. UV
observations will enable the investigator to advance knowledge in a field
which has for long had to remain a theoretical subject. RW Hya is an
eclipsing system containing a mass-losing M-giant and a hot white dwarf on
circular orbits {370 days}. The observation completed with no reported
problems.

1.28 Completed STIS/CCD/MA2 8612 (Boron in the Lithium-Rich K-Giants: A
Critical Test of Deep Stellar Mixing Versus Brown-Dwarf Ingestion)

The Space Telescope Imaging Spectrograph (CCD and MA2) was used to
observe the B I 2500Angstrom lines in four Li-rich K- giants using HST with
STIS/G230M in order to test two different evolutionary scenarios invoked to
explain the high Li abundances: the cool bottom process versus the possible
accretion of brown dwarfs/planets. There were no reported problems.

1.29 Completed Two Sets of WF/PC-2 8175 (A Survey of Gravitational
Lenses as Cosmological Tools III)

The WF/PC-2 was used to make observations of the gravitational lens
system HE2149-274. Gravitational lenses are powerful tools for studying
cosmology, galactic structure, and galaxy evolution. The observations were
completed as planned, and no anomalies were reported.

2.0 FLIGHT OPERATIONS SUMMARY:

2.1 Guide Star Acquisitions:

Scheduled Acquisitions: 47

Successful: 47

Per HSTAR 8203, the acquisition at 126/060531Z defaulted to fine
lock backup on FGS-2 only when the search radius limit was exceeded on
FGS-3. The proposals detailed in 1.2 and 1.4 may have been affected.

Scheduled Re-acquisitions: 16

Successful: 16

2.2 FHST Updates:

Scheduled: 68

Successful: 68

2.3 Operations Notes:

Using ROP SR-1A, the SSR EDAC error counter was cleared 10 times.

On two occasions, the CCS 486 status buffer limits were adjusted
per ROP DF-18A.

The STIS MCE-1 reset at 125/005923Z while the low voltage was on
and while outside any SAA interval. The STIS flight software error counter
was cleared at 125/0104Z per ROP SR-12. MAMA-1 was recovered at 125/0814Z
via normal SMS commanding.

A TTR was written for a needed re-transmit during a 486 load uplink
at 127/0615Z.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

Continuation of normal science observations and calibrations.