Status Report

NASA Hubble Space Telescope Daily Report # 3754

By SpaceRef Editor
December 13, 2004
Filed under , ,

HUBBLE SPACE TELESCOPE – Continuing to collect World Class Science

DAILY REPORT        # 3754




The Role of Groups in the Evolution of Galaxies at Intermediate

Groups are the most common environment experienced by galaxies, yet
they remain the least studied. The tidal fields and dynamical friction
encountered by galaxies in groups probably holds the key to
understanding the role of environment in driving the evolution of
galaxies since z ~ 1. To study the evolution of galaxies in the group
environment, we propose the first unbiased HST study of groups at
moderate redshifts. Unlike previous HST group samples, that relied on
radio or X-ray properties, our kinematically selected sample is drawn
from a large redshift survey and is not biased towards unusually dense
groups. HST imaging is essential to determine the morphology of
galaxies in these systems and contrast this with the properties of
galaxies in denser and more evolved groups and rich clusters at these
epochs. HST data are also required to adequately compare the
properties of groups at intermediate redshifts with local group
samples derived from the 2df and Sloan surveys. We will combine the
HST images with deep ground-based observations to study how
morphologies and stellar populations of galaxies in groups have
evolved in time. These observations are key to understanding the
decline in the volume averaged star formation rate in the universe.

S/C/NIC3 9832

A Search for Water Vapor in the Atmosphere of an Extrasolar Planet

We propose to search for evidence of water vapor in the transmission
spectrum of the transiting planet of HD 209458. A successful detection
would not only establish the presence of this important atmospheric
constituent, but would also constrain other key properties of this
close-in, Jupiter-sized planet. Specifically, relating the absorption
caused by water to that already observed from atomic sodium would help
establish the height of the atmosphere’s uppermost cloud layer {if
any}. Also, the abundance of water will provide information about that
of oxygen, and by extension, that of all heavy elements. To make this
measurement, we propose a doubly-differential procedure in which we
will use NICMOS in spectroscopic mode to detect the small spectral
changes that occur during planetary transits, and that result from
absorption of starlight as it passes through the outer parts of the
planet’s atmosphere. We search for water because it is expected to
produce by far the strongest spectrum features within the wavelength
range accessible to HST.


The Ancient Stars of M32

The question of whether the dwarf elliptical galaxy M32 contains a
population of truly ancient stars has remained unsettled for decades.
We recently used HST/WFPC2 to identify for the first time a population
of RR Lyr stars in this galaxy. Since these stars are known only to be
present in stellar populations older than 8-10 Gyr, we contend that
M32 does possess an old stellar component and certainly cannot be
comprised of only intermediate-age {~ 5 Gyr} stars as has been
frequently suggested in the literature. Our earlier observations were
insufficient to determine even the most basic photometric properties
of these stars. Nor could we use the data to identify independent
evidence of the old population that could help constrain just what
fraction of the galaxy’s stars are ancient. We propose new HST/ACS
observations to {a} get periods and luminosities of the previously
observed RR Lyr stars, {b} search for additional RR Lyr stars in a
significantly larger volume of M32, and {c} obtain ultra-deep 2-color
photometry to study the ancient main-sequence turnoff region of that
galaxy directly, {d} look for radial population gradients in M32, both
among the RR Lyr/Horizontal Branch and main- sequence populations, {e}
compare the M31/M32 old populations in terms of metallicity spread,
and {f} use the RR Lyr stars to precisely determine the relative and
possibly the absolute distances of M32 and M31’s halo.

FGS 9335

Masses of Pre-Main Sequence Binaries

We propose to continue to map the orbits of young star binaries in the
Taurus and Ophiuchus star forming regions. Our goal is to measure
their masses dynamically. This is important because there are still no
low mass young stars with reliably known masses so calculations of
their evolution to the main sequence are uncalibrated.

NIC1/NIC2/NIC3 8794

NICMOS Post-SAA calibration – CR Persistence Part 5

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 10401

A Proper Motion Search for Intermediate Mass Black Holes in Globular

Establishing the presence or absence of intermediate-mass black holes
{IMBH} in globular clusters is crucial for understanding the evolution
of dense stellar systems. We propose a systematic search for IMBHs by
conducting an imaging/proper motion study of the centers of five of
the closest, most centrally concentrated Galactic globular clusters.
ACS/HRC observations allow for accurate proper motion measurements for
stars all the way into the center of each cluster. Our approach
consists of exploiting the blue/near-ultraviolet wavelength range in
each of cycles 13 and 14, in order to dim both the bright red giants
and the background of faint red stars, hence alleviating the crowding
problems experienced by previous studies. Both filter and target
selection are critical for the success of this project, and no
previous HST program has an appropriate combination to allow proper
motion measurements for most stars into the very centers of crowded
clusters. The velocity measurements will allow us to: {i} place
constraints on the mass of a central black hole in each cluster
{detailed calculations show that the proposed observations are
sufficient to detect any central black hole with a mass as low as 3000
solar masses at the greater than 3 sigma level}; {ii} derive the
internal velocity dispersion as a function of cluster radius; {iii}
verify or reject previous reports of cluster rotation; and {iv}
directly measure any velocity anisotropy as a function of radius.


ACS CCDs daily monitor- cycle 13 – part 1

This program consists of a set of basic tests to monitor, the read
noise, the development of hot pixels and test for any source of noise
in ACS CCD detectors. The files, biases and dark will be used to
create reference files for science calibration. This programme will be
for the entire lifetime of ACS.


WFPC2 Cycle 13 CTE Monitor

Monitor CTE changes during Cycle 13.

WFPC2 10356

WFPC2 Cycle 13 Decontaminations and Associated Observations

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

NIC3 10337

The COSMOS 2-Degree ACS Survey NICMOS Parallels

The COSMOS 2-Degree ACS Survey NICMOS Parallels. This program is a
companion to program 10092.

ACS/WFC 10326

The Morphological, Photometric, and Spectroscopic Properties of
Intermediate Redshift Cluster Galaxies

We will use the ACS/WFC to image 8 fields in the outskirts of the
kT=5.8keV, X-ray cluster RX J0152-13 at z=0.83, for which we obtained
imaging in four central fields during Cycle 11. The resulting
wide-field mosaic of RX J0152-13 will enable direct study of the
population of galaxies falling into this cluster and will provide a
much needed comparison to our on-going wide-field study of the more
massive, 10.5keV cluster MS1054-03 at the same redshift. Imaging RX
J0152-13 to twice its viral radius enables us to: {1} trace the
transformation of infalling field spirals into cluster early-types
using, e.g., the morphology-density relation to large radii and very
low local densities; {2} determine the importance of galaxy-galaxy
interactions, i.e., whether the frequency of such encounters in the
infall region is as unexpectedly high as found in MS1054-03; and {3}
study in detail the star-formation histories of the most recently
accreted members via accurate colors and morphologies. A comparison of
RX J0152-13 with MS1054-03 will also allow us to directly probe the
dependence of galaxy evolution on cluster mass. Only by pairing the
wide-field ACS mosaic of RX J0152-13 with multi-object spectroscopy
from the Magellan, Keck, and VLT telescopes can we test predictions
from galaxy formation models, understand how field spirals evolve into
early-type cluster members, and better constrain the formation of
galaxies in general.

ACS/HRC 10272

A Snapshot Survey of the Sites of Recent, Nearby Supernovae

During the past few years, robotic {or nearly robotic} searches for
supernovae {SNe}, most notably our Lick Observatory Supernova Search
{LOSS}, have found hundreds of SNe, many of them in quite nearby
galaxies {cz < 4000 km/s}. Most of the objects were discovered before maximum brightness, and have follow-up photometry and spectroscopy; they include some of the best-studied SNe to date. We propose to conduct a snapshot imaging survey of the sites of some of these nearby objects, to obtain late-time photometry that {through the shape of the light and color curves} will help reveal the origin of their lingering energy. The images will also provide high- resolution information on the local environment of SNe that are far superior to what we can procure from the ground. For example, we will obtain color-color and color-magnitude diagrams of stars in these SN sites, to determine their progenitor masses and constraints on the reddening. Recovery of the SNe in the new HST images will also allow us to actually pinpoint their progenitor stars in cases where pre-explosion images exist in the HST archive. Use of ACS rather than WFPC2 will make our snapshot survey even more valuable than our Cycle 9 survey. This Proposal is complementary to our Cycle 13 archival proposal, in which we outline a plan for using existing HST images to glean information about SN environments.


The Formation History of Andromeda

We propose deep observations of Andromeda’s outer disk and giant tidal
stream, to reconstruct their star formation histories. As the nearest
giant galaxy, Andromeda offers the best testing ground for
understanding galaxy formation and evolution. Given the dramatic
increase in sensitivity offered by the ACS, we can now resolve stars
on the old main sequence in the other giant spiral of the Local Group,
and employ the same direct age diagnostics that have been used for
decades in the study of Galactic globular clusters. In Cycle 11, we
successfully observed a field in the Andromeda halo and constructed a
deep color-magnitude diagram reaching well below the oldest main
sequence turnoff. In Cycle 13, we propose to extend these observations
to the outer disk and tidal stream of Andromeda, to constrain their
star formation histories and compare them to that of the halo. The
combined observations from these two programs will offer a dramatic
advance in our understanding of the overall evolution of spiral

ACS/HRC 10253

A UV Survey of Quiescent Black Holes and Neutron Stars

Existing STIS observations of quiescent Galactic black hole and
neutron star binaries suggest a striking difference between them. The
spectra of black holes appear to drop off steeply in the near-UV,
whereas those of neutron stars continue to rise, at least down to
1700A. This difference has been interpreted in terms of advective
accretion models, and may indicate a fundamental signature of the two
types of object. The existing data do not include enough objects to
form a representative sample, however. We will exploit the faint
source sensitivity of ACS to perform a survey of the UV spectral
shapes across a larger sample containing both black holes and neutron
stars. This survey will test the assertion that their UV spectra are
strikingly different; allow modelling of the broad band spectral
energy distribution; test for variability in the UV flux; and identify
suitable targets for subsequent spectroscopic follow-up..

ACS/WFC 10252

Improving the Astrometric Calibration of ACS/WFC for the Most Useful

The distortion correction for the WFC, with which most ACS astrometry
is done, is filter- dependent, and is not sufficiently accurate for
the most useful filters to the community, F606W and F814W. We propose
to derive improved corrections using 1 orbit for each filter. A
by-product will be an astrometric standard field at the center of
Omega Centauri.

ACS/WFC 10237

Low-Ionization BALs: Evolution or Orientation?

We propose to test the hypothesis that Low-Ionization Broad Absorption
Line Quasars {LoBALs} represent a special stage of quasar evolution:
young quasars in systems with strong interaction and star-formation.
We will carry out high resolution imaging using ACS/WFC and NICMOS to
measure the properties of the host galaxies of four LoBAL quasars at z
= 0.9 – 2.0 that show strong overlapping FeII absorption troughs. The
ACS imaging will be carried out in the passband with the strongest BAL
absorption, acting as a natural coronagraph. This results in a
reduction of quasar light by a factor of 15 – 26 in these passbands,
providing arguably the best view of the host galaxies of luminous,
high-redshift quasars. This method allows efficient detection and
detailed modeling of the host galaxy morphology in the rest-frame
ultraviolet, which is most sensitive to star formation and galaxy
interaction. We will also use NICMOS imaging to measure the rest-
frame light from the host galaxy to probe the old stellar populations
where the host galaxy is likely to be brighter. It has been suggested
that LoBALs might not be explained simply as an orientation effect but
rather as an early phase of quasar evolution. Such a phase is
typically associated with large amounts of dust and gas, and young
galaxies with strong star formation. With HST observations, we will
study the color and morphology of the FeLoBAL quasar host galaxies,
and measure the age of their dominant stellar populations. We will
also measure the density of close companions, and, in particular, look
for signs of ongoing or recent mergers. These measurements will be
compared to those of control samples of normal quasars at similar
redshift. If LoBALs are indeed young systems, then their host galaxies
are expected to show stronger interactions and merger activity,
younger stellar ages, and regions with strong star formation. If the
LoBAL host galaxies show no significant difference from those of
normal quasars, it will support the view that LoBAL quasars are not a
distinct population and that all quasars have BAL outflows along some
lines of sight.

ACS/HRC 10199

The Most Massive Galaxies in the Universe: Double Trouble?

We are proposing an HST snapshot survey of 70 objects with velocity
dispersion larger than 350 km/s, selected from the Sloan Digital Sky
Survey. Potentially this sample contains the most massive galaxies in
the Universe. Some of these objects may be superpositions; HST imaging
is the key to determining if they are single and massive or if they
are two objects in projection. The objects which HST imaging shows to
be single objects are interesting because they potentially harbor the
most massive black holes, and because their existence places strong
constraints on galaxy formation models. When combined with ground
based data already in hand, the objects which HST imaging shows are
superpositions provide valuable information about interaction rates of
early- type galaxies as well as their dust content. They also
constrain the allowed parameter space for models of binary
gravitational lenses {such models are currently invoked to explain
discrepancies in the distribution of lensed image flux ratios and

ACS/HRC 10185

When does Bipolarity Impose itself on the Extreme Mass Outflows from
AGB Stars? An ACS SNAPshot Survey

Essentially all well-characterized preplanetary nebulae {PPNe} —
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? Our previous SNAPshot surveys of a PPNe sample {with
ACS & NICMOS} show that roughly half our targets observed are
resolved, with well-defined bipolar or multipolar morphologies.
Spectroscopic surveys of our sample confirm that these objects have
not yet evolved into planetary nebulae. Thus, the transformation from
spherical to aspherical geometries has already fully developed by the
time these dying stars have become preplanetary nebulae. From this new
and surprising result, we hypothesize that the transformation to
bipolarity begins during the very late AGB phase, and happens very
quickly, just before, or as the stars are evolving off the AGB. We
propose to test this hypothesis quantitatively, through a SNAPshot
imaging survey of very evolved AGB stars which we believe are nascent
preplanetary nebulae; with our target list being drawn from published
lists of AGB stars with detected heavy mass-loss {from millimeter-wave
observations}. This survey is crucial for determining how and when the
bipolar geometry asserts itself. Supporting kinematic observations
using long-slit optical spectroscopy {with the Keck}, millimeter and
radio interferometric observations {with OVRO, VLA & VLBA} are being
undertaken. The results from this survey {together with our previous
work} will allow us to draw general conclusions about the onset of
bipolar mass-ejection during late stellar evolution, and will provide
crucial input for theories of post-AGB stellar evolution. Our survey
will produce an archival legacy of long-standing value for future
studies of dying stars.

NIC2 10173

Infrared Snapshots of 3CR Radio Galaxies

Radio galaxies are an important class of extragalactic objects: they
are one of the most energetic astrophysical phenomena and they provide
an exceptional probe of the evolving Universe, lying typically in high
density regions but well-represented across a wide redshift range. In
earlier Cycles we carried out extensive HST observations of the 3CR
sources in order to acquire a complete and quantitative inventory of
the structure, contents and evolution of these important objects.
Amongst the results, we discovered new optical jets, dust lanes,
face-on disks with optical jets, and revealed point-like nuclei whose
properties support FR-I/BL Lac unified schemes. Here, we propose to
obtain NICMOS infrared images of 3CR sources with z<0.3 as a major enhancement to an already superb dataset. We aim to deshroud dusty galaxies, study the underlying host galaxy free from the distorting effects of dust, locate hidden regions of star formation and establish the physical characteristics of the dust itself. We will measure frequency and spectral energy distributions of point-like nuclei, expected to be stronger and more prevalent in the IR, seek spectral turnovers in known synchrotron jets and find new jets. We will strongly test unified AGN schemes and merge these data with existing X-ray to radio observations. The resulting database will be an incredibly valuable resource to the astronomical community for years to come.

ACS/SBC 10125

Where is the Wind in 1H0707-495?

We propose three observations using the narrow-line Seyfert 1 galaxy
1H 0707-495 to be coordinated with already-approved deep exposures
using FUSE. A previous HST observation of 1H 0707-495 revealed
strongly blueshifted high-ionization lines, suggesting an origin in an
outflowing wind. Detailed photoionization modeling reveals that the
wind line fluxes and ratios are consistent with two solutions: a
high-density, high- column solution, originating close to the central
engine, and a low-density, low-column solution, located much further
out. These two locations, interestingly, correspond to those predicted
by two different physical models for winds in AGNs. We can
differentiate between these models by observing emission line
variability on two time scales, and examining relative variability of
OVI obtained by FUSE and CIV and other lines obtained by HST. We will
also look for profile variability, constrain velocity ionization
stratification through a detailed study of the profiles, and
investigate metallicity, which has been suggested to be high in NLS1s.
This program, requiring only a modest amount of time, is expected to
make significant contributions to our understanding of outflows in
AGN, and the structure, origin and metallicity of the broad- line


The COSMOS 2-Degree ACS Survey

We will undertake a 2 square degree imaging survey {Cosmic Evolution
Survey — COSMOS} with ACS in the I {F814W} band of the VIMOS
equatorial field. This wide field survey is essential to understand
the interplay between Large Scale Structure {LSS} evolution and the
formation of galaxies, dark matter and AGNs and is the one region of
parameter space completely unexplored at present by HST. The
equatorial field was selected for its accessibility to all
ground-based telescopes and low IR background and because it will
eventually contain ~100, 000 galaxy spectra from the VLT-VIMOS
instrument. The imaging will detect over 2 million objects with I> 27
mag {AB, 10 sigma}, over 35, 000 Lyman Break Galaxies {LBGs} and
extremely red galaxies out to z ~ 5. COSMOS is the only HST project
specifically designed to probe the formation and evolution of
structures ranging from galaxies up to Coma-size clusters in the epoch
of peak galaxy, AGN, star and cluster formation {z ~0.5 to 3}. The
size of the largest structures necessitate the 2 degree field. Our
team is committed to the assembly of several public ancillary datasets
including the optical spectra, deep XMM and VLA imaging, ground-based
optical/IR imaging, UV imaging from GALEX and IR data from SIRTF.
Combining the full-spectrum multiwavelength imaging and spectroscopic
coverage with ACS sub-kpc resolution, COSMOS will be Hubble’s ultimate
legacy for understanding the evolution of both the visible and dark


Significant Spacecraft Anomalies: (The following are preliminary
reports of potential non-nominal performance that will be

HSTAR 9625: During LOS , FHST Update U2,3FM scheduled @ 345/22:07:40Z
resulted in Error Box results failure indicating “2 FAILED”. One 486
Status Buffer 901 message was observed. Subsequent GS Acquisition
(1,2,1) passed. Under investigation.

HSTAR 9627: During ZOE, GS Acquisition @ 347/17:02:39Z failed due to
SRLE on FGS 2 and 3. FHST Updates @ 347/16:56Z showed error of
94.341, 420, and -28.474 and 0.001, 1.524, and 1.918 arcsec. FHST Map
@ 347/17:10Z was occulted when exited ZOE. Next GS Acquisition
(2,3,2) @ 347/18:38:39Z was successful. Under investigation.


17350-0 Restoration of TGS FHST Moving Target Limits @ 347/23:24z

17339-0 Three Gyro Command Generator Restoration @ 347/23:32:32z


1290-0 Adjust Recharge Ratio Limit for High Sun/Orbit Time @ 345/14:07z

                          SCHEDULED     SUCCESSFUL    FAILURE TIMES 
FGS Gsacq                36                        35            See Hstar 
# 9627 
FGS Reacq                16                        16 
FHST Update              58                        57            See Hstar 
# 9625 


At the completion of the Two Gyro Science (TGS) On-Orbit Test (OOT),
Day 3 testing, the Vehicle Slew Command Generator must be returned to
the pre-TGS OOT, Three Gyro values to correctly maintain RWA wheel
speeds. Successfully restored Three Gyro Command Generator parameters
@ 347/23:32Z (OR 17339 with attached script). Verified during first
major vehicle maneuver. GS Acquisition @348/02:15Z was successful,
wheel speeds and torques were nominal throughout maneuver.

The TGS FHST Moving Target limits were modified to support previous
TGS testing. Software modifications are planned to replace the need
for the limits modifications, as such the previous limits need to be
restored. The Rate Damping Mode limits do not need to be modified.
Successfully restored FHST Moving Target Limits @ 347/23:24Z (OR 17350
with attached script).

SpaceRef staff editor.