Status Report

NASA Hubble Space Telescope Daily Rpeort # 3387

By SpaceRef Editor
June 19, 2003
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NICMOS Post-SAA calibration – CR Persistence Part 2

A new procedure proposed to alleviate the CR-persistence problem of
NICMOS. Dark frames will be obtained immediately upon exiting the SAA
contour 23, and every time a NICMOS exposure is scheduled within 50
minutes of coming out of the SAA. The darks will be obtained in
parallel in all three NICMOS Cameras. The POST-SAA darks will be
non-standard reference files available to users with a USEAFTER
date/time mark. The keyword ‘USEAFTER=date/time’ will also be added to
the header of each POST-SAA DARK frame. The keyword must be populated
with the time, in addition to the date, because HST crosses the SAA ~8
times per day so each POST-SAA DARK will need to have the appropriate
time specified, for users to identify the ones they need. Both the raw
and processed images will be archived as POST-SAA DARKSs. Generally we
expect that all NICMOS science/calibration observations started within
50 minutes of leaving an SAA will need such maps to remove the CR
persistence from the science images. Each observation will need its
own CRMAP, as different SAA passages leave different imprints on the
NICMOS detectors.

ACS/HRC 9379

Near Ultraviolet Imaging of Seyfert Galaxies: Understanding the
Starburst-AGN Connection

We propose a near-UV snapshot survey of 101 Seyfert galaxies using
ACS/HRC and the filter F330W, a configuration which is optimal to
detect faint star forming regions around their nuclei. These images
will complement optical and near-IR images available in the HST
archive, thus providing a panchromatic atlas of the inner regions of
active galaxies, which we will use to study the starburst-AGN
connection. The main goals of this proposal are: {1} Determine the
frequency of circumnuclear starbursts in Seyferts, down to levels
which cannot be observed from the ground; {2} characterize the
observational {fluxes, colors, structure, sizes} and intrinsic
{luminosities, masses, ages, global star-formation rate} properties of
these clusters; {3} derive the luminosity functions of young star
clusters around the nucleus of Seyferts and compare these results with
those from normal and starburst galaxies to determine their survival
rate close to the AGN; {4} address questions about the relation
between AGNs and starbursts, like the possible connection between the
masses and luminosities of black holes and starbursts, and the
implications for the evolution of the black holes and their host
galaxy bulges. By adding UV images to the existing optical and near-IR
ones, this project will create an extremely valuable database for
astronomers with a broad range of scientific interests, from the
properties of the AGN to the properties of their host galaxies.

ACS/WFC 9419

The Complete IMF of a Massive Young Cluster

We propose to use the large improvement in sensitivity and wide-field
resolution provided by ACS to obtain for the first time the complete ~
0.1 M_Sun to ~ 100 M_Sun IMF of a single massive young cluster. We
will obtain BVI + nebular deep {V ~ 27} WFC photometry of six cluster
and one background pointings and we will use the auto-parallel
capacity of ACS to simultaneously acquire deep NUV+U+V photometry of
selected regions in the cluster. Special care has been taken to treat
all the complications which arise in the reduction of data for the
purpose of calculating the IMF of a young cluster. We have chosen as
our object of study N11 in the LMC because it arguably provides the
best combination of stellar mass range {> 40 O stars, with several O3
stars}, spatial resolution {1 WFC pixel = 0.0125 pc}, low extinction
{E{B-V} ~ 0.1}, crowding, background confusion, and nebular
contamination in comparison to other Galactic and Local Group
clusters. It also has the advantage of having two separate regions,
one which has already stopped forming stars and another one which is
still forming them, thus allowing us to search for differences in the
IMF between those two cases. The ACS data will be complemented with IR
ground-based observations obtained using Gemini South, for which we
already have been awarded time.


NICMOS Observations of Transient Infrared Jets in the Galactic
Microquasar GRS1915+105

We propose to use HST/NICMOS to make Target of Opportunity
observations of the galactic microquasar GRS1915+105. This source
possesses transient radio jets which exhibit apparent superluminal
motions, and resolved infrared emission from these jets has been
observed in GRS1915+105 {Sams, Eckart, and Sunyaev, 1996; Eikenberry
and Fazio, 1996}. Because the jet ejection events are correlated with
X-ray outbursts, we will use observations of X-ray flares with the
Rossi X-Ray Timing Explorer to trigger the HST observations. We will
then monitor GRS1915+105 periodically with NICMOS, obtaining relative
astrometry, photometry, polarimetry, and grism spectroscopy of the
jets and the parent object. These observations will allow us to
greatly increase our understanding of the jets’ radiative mechanisms
and physical conditions, and their evolution with time. We require the
capabilities of HST and NICMOS due to the small angular separations
between the jets and the parent object {increasing from ~ 0.1 to ~ 0.8
arcsec over the span of the TOO observations} and the high reddening
towards GRS1915+105 {A_V ~ 30 mag}.

ACS 9463

Are OH/IR stars the youngest post-AGB stars? An ACS SNAPshot imaging

Essentially all well-characterized preplanetary nebulae {PPNs}–
objects in transition between the AGB and planetary nebula
evolutionary phases – are bipolar, whereas the mass-loss envelopes of
AGB stars are strikingly spherical. In order to understand the
processes leading to bipolar mass-ejection, we need to know at what
stage of stellar evolution does bipolarity in the mass-loss first
manifest itself? We have recently hypothesized that most OH/IR stars
{evolved mass- losing stars with OH maser emission} are very young
PPNe. We propose an ACS/SNAPshot imaging survey of a large,
morphologically unbiased sample of these objects, selected using their
IRAS 12-to-25micron colors. Our ground-based imaging study of OH/IR
stars has revealed a few compact bipolar objects, supporting our
hypothesis. However since most objects remain unresolved, HST
observations are needed to determine how and when the bipolar geometry
asserts itself. Our complementary program of interferometric mapping
of the OH maser emission in our sources is yielding kinematic
information with spatial resolution comparable to that in the HST
images. The HST/radio data will provide crucial input for theories of
post-AGB stellar evolution. In addition, these data will also indicate
whether the multiple concentric rings, “searchlight beams”, and
truncated equatorial disks recently discovered with HST in a few PPNs,
are common or rare phenomena.


Completing A Near-Infrared Search for Very Low Mass Companions to
Stars within 10 pc of the Sun

Most stars are fainter and less massive than the Sun. Nevertheless,
our knowledge of very low mass {VLM} red dwarfs and their brown dwarf
cousins is quite limited. Unknown are the true luminosity function
{LF}, multiplicity fraction, mass function, and mass-luminosity
relation for red and brown dwarfs, though they dominate the Galaxy in
both numbers and total mass. The best way to constrain these relations
is a search for faint companions to nearby stars. Such a search has
several advantages over field surveys, including greater sensitivity
to VLM objects and the availability of precise parallaxes from which
luminosities and masses can be derived. We propose to complete our
four-filter NICMOS snapshot search for companions to stars within 10
pc. With a 10 sigma detection limit of M_J ~ 20 at 10 pc, we can
detect companions between 10 and 100 AU that are at least 9 mag
fainter than the empirical end of the main sequence and at least 6.5
mag fainter than the brown dwarf Gl 229B. When completed, our search
will be the largest, most sensitive, volume-limited search for VLM
companions ever undertaken. Our four-filter search will permit
unambiguous identification of VLM-companion candidates for follow-up
observation. Together with IR speckle and deep imaging surveys, our
program will firmly establish the LF for VLM companions at separations
of 1-1000 AU and the multiplicity fraction of all stars within 10 pc.

STIS 9504

Probing the Halo and ISM of Low-Redshift Galaxies with Young Supernovae

We propose a Target of Opportunity program to study the halo and ISM
of a low-redshift galaxy hosting a bright new supernova {V<= 14}. The
primary objectives are to characterize the ionization state, gas-phase
abundances, metallicity, and gas kinematics in the ISM and halo of the
host galaxy, and, if the properties of the sightline are favorable, in
the intervening intergalactic medium. Core-collapse supernovae
occurring in galaxies out to the Virgo cluster are the potential
targets for this program. The principal spectral region for this study
is the short-wavelength ultraviolet {wl <1700Angstrom} using STIS
echelle spectra, which provide a comprehensive set of lines to study
the hot, warm, and cool phases of the ISM. The HST spectra will be
augmented by FUSE TOO observations {900<Lambda<1185Angstrom} of the
same object for which we already have allocated time. New
core-collapse supernovae, with their strong, nearly featureless UV
continua, provide outstanding opportunities to obtain high-quality
absorption line spectra of the gas on the line of sight to the SN, but
only if the observations are executed within ~1 week of outburst. Our
team has the experience and extensive ground-based support to promptly
assess the suitability of each newly-discovered supernova for this
program and to quickly provide all the necessary data to rapidly
execute the observations.

WFPC2 9589

WFPC2 Decontaminations and Associated Observations Pt. 1/3

This proposal is for the monthly WFPC2 decons. Also included are
instrument monitors tied to decons: photometric stability check, focus
monitor, pre- and post-decon internals {bias, intflats, kspots, &
darks}, UV throughput check, VISFLAT sweep, and internal UV flat

WFPC2 9595


This dark calibration program obtains 3 dark frames every day to
provide data for monitoring and characterizing the evolution of hot

STIS 9606

CCD Dark Monitor-Part 2

Monitor the darks for the STIS CCD.

STIS 9608

CCD Bias Monitor – Part 2

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.

STIS 9615

Cycle 11 MAMA Dark Monitor

This test performs the routine monitoring of the MAMA detector dark
noise. This proposal will provide the primary means of checking on
health of the MAMA detectors systems through frequent monitoring of
the background count rate. The purpose is to look for evidence of
change in dark indicative of detector problem developing.

STIS 9633

STIS parallel archive proposal – Nearby Galaxies – Imaging and

Using parallel opportunities with STIS which were not allocated by the
TAC, we propose to obtain deep STIS imagery with both the Clear
{50CCD} and Long-Pass {F28X50LP} filters in order to make
color-magnitude diagrams and luminosity functions for nearby galaxies.
For local group galaxies, we also include G750L slitless spectroscopy
to search for e.g., Carbon stars, late M giants and S-type stars. This
survey will be useful to study the star formation histories, chemical
evolution, and distances to these galaxies. These data will be placed
immediately into the Hubble Data Archive.

ACS 9658

ACS Earth Flats

This program will obtain sequences of flat field images by observing
the bright Earth. Several UV filters from the interim calibration
program {9564} require additional exposures to obtain the required
illumination. A few UV filters from this program will be repeated to
monitor for changes in the flat fields and to verify the interim
results. Since no streaks are observed in the UV, the wavelength
coverage is extended to longer wavelengths in order to explore the
severity of streaks in the flats from clouds in the FOV. We have added
exposures for the HRC in the visible filters to verify the results
derived from the L-flat campaign and to explore the severity of
streaks. We have also added exposures on WFC using the minimum
exposure time and using filters which will not saturate the brightest
WFC pixel by more than 10 times the full well.

ACS 9674

CCD Daily Monitor

This program consists of basic tests to monitor, the read noise, the
development of hot pixels and test for any source of noise in ACS CCD
detectors. This programme will be executed once a day for the entire
lifetime of ACS.

STIS 9708

STIS Pure Parallel Imaging Program: Cycle 11

This is the default archival pure parallel program for STIS during cycle


Significant Spacecraft Anomalies: (The following are preliminary
reports of potential non-nominal performance that will be
investigated.) None


16992-0 GenSlew Request for Proposal 9100-Slot 1 @169/2229z

16993-0 GenSlew Request for Proposal 9100-Slot 2 @169/2231z

OPS NOTES EXECUTED: 1123-0 CCS Ops String Cleanup Post-FSW 2.3 C
Installation (All Strings) @ 169/1725z

                           SCHEDULED     SUCCESSFUL    FAILURE TIMES
FGS GSacq                8                         8
FGS REacq                5                         5
FHST Update              21                       21


Executed SI General Purpose Slew (GENSLEW) for Proposal 9100, Slot 1 @
169/22:29Z and Slot 2 @ 169/22:31Z (Ors 16992 and 16993). These
GENSLEWs were executed to remove drift in the position of the ACS
coronagraphic spot.

Successfully completed VEST-SIMSS Interface Validation testing Day 168
and 169. Testing was executed from the SMOR using the CCS "B" String
with PRD O06100TR1. VEST structure was the data source. Verified
SIMSS interface supports various command and telemetry functionality
between the STOCC and VEST in both OPS and SM configurations.
Verified capability to ingest 0.5, 4, and 32 kbps Q-channel (OPS mode)
and PDI/Ku-band (SM mode), HST486 memory dump, NSSC-1 ESB via
I-channel, SSR engineering and science data playbacks, and general
commanding in TDRSS (OPS) and JSC (SM ) modes. Also verified Ground
System configuration to support data flow and command between VEST and
STOCC via Packet Filter 13, residing on the SIMLAN which housed the
SOC MCCSIM. Test revealed one problem: During SSR record of 1 Mbps
science fill data, with the COM module configured for for science,
some how data was "seen" at the I-channel port of the SIMSS. The
I-channel problem was not encountered during the Day 169 testing.

SpaceRef staff editor.