Daily #3952

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT # 3952

PERIOD COVERED: UT September 23,24,25, 2005 (DOY 266,267,268)

OBSERVATIONS SCHEDULED

NIC1/NIC2/NIC3 8793

NICMOS Post-SAA calibration - CR Persistence Part 4

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.

S/C 4974

TRTTEST

The Transcient Response Test is for the periodic performance
monitoring of the FGS 2R servo A mechanism.

ACS/HRC 10623

HST Optical Snapshot Survey of Intermediate Redshift Ultraluminous
Infrared Galaxies

Ultraluminous infrared galaxies {ULIGs} are commonly believed to be a
transitory phase in the evolution of disk galaxy mergers into QSOs.
However, a recently reported discrepancy between the morphological and
structural properties of z 0.13 ULIGs and z = 0.12-0.25 QSOs with
M{V} -23.5 has cast doubt on their evolutionary connection. We
propose an ACS snapshot survey of a sample of 39 ULIGs with z =
0.35-1.0. These galaxies are the best suited for comparison with
luminous z=0.12-0.25 QSOs because {1} they are at larger lookback
times than local ULIGs, and thus are likely representative of the
systems that evolve into lower redshift luminous QSOs, {2} they have
luminosities comparable to luminous QSOs and, {3} they are selected in
a manner that biases the sample towards harboring imbedded AGN, and
thus are the most likely precursors to optical QSOs. High resolution
HST ACS images will allow a determination of galaxy morphology and
reveal the presence of bright AGN. The 2-D profile of each galaxy will
be modeled using GALFIT, with the AGN comprising one component of the
fit where applicable to better characterize the underlying galaxy.
Fundamental parameters {effective radius and surface brightness, and
F814W-band magnitude} of the underlying galaxy will thus be measured
and compared with the host galaxies of the luminous QSO sample. This
imaging campaign will consume a modest amount of HST time, but will
provide for the first time a statistically significant view of ULIGs
at look-back times of 30-65% the age of the universe, and sufficient
resolution and sensitivity to conduct a meaningful comparison with
z=0.12-0.25 QSOs, as well as with local {z 0.3} IRAS-detected and
distant {z 2} SCUBA-detected ULIGs.

NIC2 10620

Massive Star Formation and the Proper Motions of the OMC-1 Molecular
Hydrogen Fingers

The Orion Molecular Cloud OMC-1 is by far the nearest region of
massive star formation, and as such provides a laboratory for studying
massive star formation with unprecedented detail. Using NICMOS, eight
years ago our group discovered unique molecular hydrogen 'fingers'
emanating from the IRc2 area. We propose new NICMOS imaging of the
same region to compare with our earlier results. This will determine
spatial motions to ~3 AU/year. Using the two data sets, we will: 1}
bound the age range of the features and thus address whether all the
molecular hydrogen features were produced in a single event - such as
an explosion or a stellar merger - or in multiple events/steady
outflow; 2} limit the location of the outflow source{s}, which remain
to be identified despite sub-arcsecond imaging at thermal infrared
wavelengths; and 3} characterize inhomogeneities on the 100 AU scale.
Together these findings will significantly constrain how massive star
formation proceeds in OMC-1. NICMOS achieves the highest quality,
near-infrared images for diffuse objects in crowded regions. Because
of the complexity of the OMC-1 region, and the difficulty in using
Adaptive Optics to measure small position shifts for diffuse, low
contrast objects, these high precision proper motion measurements
require the stable PSF, high Strehl ratio, and low response in the PSF
wings which HST/NICMOS uniquely provides.

NIC2 10603

Multiwavelength Imaging of Edge-on Protoplanetary Disks: Quantifying
the Growth of Circumstellar Dust

Young, edge-on circumstellar disks are uniquely valuable laboratories
for the study of planet formation. In these objects, the central star
is occulted from direct view, significant PSF artifacts are absent,
and the disk is clearly seen as a central dust lane flanked by faint
disk reflected light. The detailed morphology of these nebulae and its
variation with wavelength provide crucial information on the disk
internal structure and the properties of its constituent dust grains.
A key observable is the slope defining the wavelength dependence of
the dust scattering opacity, which becomes shallower when grain growth
has taken place; multiwavelength resolved disk images are the key
dataset enabling such measurements. Recent analyses of three different
edge-on disks have revealed a diversity in their dust properties that
is indicative of different degrees of dust grain evolution having
taken place in each system. This characterization of disk grain
growth, when applied comparatively to a larger sample of these
objects, would enable the construction of an evolutionary sequence of
young disks at successive stages on the road to planet formation. In
pursuit of this goal, we have identified a sample of 15 edge-on disks
previously discovered by HST or groundbased telescopes, but for which
high fidelity, high spatial resolution images do not yet exist in both
the optical and near-infrared. We propose broad-band multicolor
imaging with NICMOS of all these targets, and ACS imaging of nine of
these targets In combination with existing data, the proposed images
will form a complete database of high resolution optical/near-IR
images for these 15 disk systems. Scattered light modeling will be
used to derive the disk structure and dust properties, yielding
results that will be of fundamental importance for our understanding
of grain properties during protoplanetary disk evolution.

ACS/HRC 10572

Resolving M32's Main Sequence: A Critical Test for Stellar Population
Studies

We propose to observe the M32 main-sequence turnoff {MSTO} with deep
ACS/HRC B and V images. Only the superior resolution and blue
sensitivity of ACS/HRC make this possible. M32 is the only elliptical
galaxy close enough to allow direct observation of its MSTO - it is a
vital laboratory for deciphering the stellar populations of all other
elliptical galaxies, which can only be studied by the spectra of their
integrated light, given their greater distances. Major questions about
M32's star formation history remain unanswered. Spectral studies
suggest that M32 underwent a recent burst of star formation 3 to 8
billion years ago; observation of the M32 MSTO will confirm this
directly. In the process, ACS will easily resolve more luminous
components: hot blue stars, luminous, intermediate-age red clump and
AGB stars, and any extended blue horizontal branch. These detailed
CMDs will provide a direct comparison with population synthesis models
for M32, providing a bridge to studies of the integrated light of more
distant elliptical galaxies, a crucial ingredient for understanding
their star formation histories. As M32 is projected against the edge
of the M31 disk, an essential part of our proposal includes deep
observation of an M31 disk field to allow the M32 photometry to be
background corrected. These observations will reveal the star
formation history of M31's outer disk and are thus of interest in
their own right.

ACS/WFC/WFPC2 10558

Archaeology of Fossil Galaxy Groups

Fossil groups are concentrations of dark matter with masses and x-ray
luminosities comparable to those of an entire group of galaxies, but
whose light is dominated by a single, isolated, large elliptical
galaxy. The origin of these systems remains a puzzle: they may be the
end products of complete merging of galaxies within once normal
groups, or they might originate from a very unusual galaxy luminosity
function in those regions that inhibits the formation of
moderate-sized galaxies. We propose the first study of the globular
cluster populations of the dominant elliptical galaxies in fossil
galaxy groups, which will provide important new insights into their
origin.

ACS/HRC 10556

Neutral Gas at Redshift z=0.5

Damped Lyman-alpha systems {DLAs} are used to track the bulk of the
neutral hydrogen gas in the Universe. Prior to HST UV spectroscopy,
they could only be studied from the ground at redshifts z1.65.
However, HST has now permitted us to discover 41 DLAs at z1.65 in our
previous surveys. Followup studies of these systems are providing a
wealth of information about the evolution of the neutral gas phase
component of the Universe. But one problem is that these 41
low-redshift systems are spread over a wide range of redshifts
spanning nearly 70% of the age of the Universe. Consequently, past
surveys for low-redshift DLAs have not been able to offer very good
precision in any small redshift regime. Here we propose an ACS-HRC-
PR200L spectroscopic survey in the redshift interval z=[0.37, 0.7]
which we estimate will permit us to discover another 41 DLAs. This
will not only allow us to double the number of low-redshift DLAs, but
it will also provide a relatively high-precision regime in the
low-redshift Universe that can be used to anchor evolutionary studies.
Fortunately DLAs have high absorption equivalent width, so
ACS-HRC-PR200L has high-enough resoultion to perform this proposed
MgII-selected DLA survey.

ACS/HRC 10525

Characterizing the Near-UV Environment of M Dwarfs: Implications for
Extrasolar Planetary Searches and Astrobiology

We propose SNAP observations with the ACS HRC PR200L prism, designed
to measure the near ultraviolet emission in a sample of 107 nearby M
dwarfs. The sample spans the mass range from 0.1 - 0.6 solar masses
{temperature range 2200K - 4000K} where the UV energy distributions
vary widely between active and inactive stars. The strength and
distribution of this UV emission can have critical consequences for
the atmospheres of attendant planets. Our proposed observations will
provide desperately needed constraints on models of the habitability
zone and the atmospheres of possible terrestrial planets orbiting M
dwarf hosts, and will be used to sharpen TPF target selection. In
addition, the NUV data will be used in conjunction with existing
optical, FUV and X-ray data to constrain a new generation of M dwarf
atmospheric models, and to explore unanswered questions regarding the
dynamo generation and magnetic heating in these low-mass stars.

NIC2 10510

Morphology of massive early-type galaxies at z1.2: constraining
galaxy formation models

We ask for NICMOS-NIC2 H-band imaging of a sample of 10 massive
early-type galaxies spectroscopically identified at 1.2z1.7. Our aim
is to look for possible relics of merging events of their
formation/evolution in their morphology. The requested observations,
sampling their rest- frame at lambda6500A, would map the mass
distribution of the bulk of their stellar content. The targets have
been revealed by our group on the basis of near-IR spectroscopy
obtained in the framework of a spectroscopic survey of a complete
sample of bright EROs {Ks18.5}. Optical and near-IR photometry is
available for all the targets, and low resolution near-IR spectra have
allowed their identification and redshift measurement. Spectroscopic
and photometric data in our hands show that they have already
assembled stellar masses greater than 3 10^11 solar masses, and that
the mean age of their stellar population is estimated older than 2-3
Gyr for 6 of them and about 1 Gyr for the other 4 galaxies. Thus, they
are among the most luminous and massive evolved galaxies detected so
far at z1. Other data are needed to infer how they have assembled
such high stellar masses, i.e. to trace back their evolution. The
requested observations would allow us to reveal signs of past
interaction/merger event. A smooth r^{1/m} profile, coupled with no
other signs of interaction/merger {disturbed morphology}, would place
the possible merger event of formation 1-2 Gyr before their redshift z
pprox 1.5, i.e. at z 2-3. On the other hand, if signs of recent
merger events will be found, the last merger event forming the local
massive spheroids will be constrained at 1.5 z 2. Thus, the
requested HST observations will allow for the first time to see how
massive early-type galaxies at z pprox 1.5 look like, constraining in
any case the redshift of the possible merging event of their
formation.

ACS/HRC 10488

The Most Massive Galaxies in the Universe: Color-Gradients and Texture

We are proposing an HST snapshot survey of 40 objects with velocity
dispersion larger than 350 km/s, selected from the Sloan Digital Sky
Survey and confirmed to be single massive galaxies by the ACS-HRC
i-band imaging obtained during Cycle 13. This sample of the most
massive galaxies in the Universe is interesting because these objects
potentially harbor the most massive black holes, and because their
existence places strong constraints on galaxy formation models. These
objects are unusual for another reason than their abnormally large
velocity dispersions: they appear to be bluer than expected from
extrapolation of the color-velocity dispersion relation of normal
early-types to these large velocity dispersions. The bluer than
expected colors indicate that the formation histories of these objects
are likely to be rather different than for normal early-types. This
difference is also expected to manifest as abnormal color-gradients.
ACS-HRC imaging in one other band {i.e. the g-band} will allow us not
simply to analyze color gradients in these objects but also to study
their color texture and topology. This study will provide important
information about the formation history of galaxies.

ACS/HRC/WFC 10487

A Search for Debris Disks in the Coeval Beta Pictoris Moving Group

Resolved observations of debris disks present us with the opportunity
of studying planetary evolution in other solar systems. We propose to
search for debris disks in the Beta Pictoris moving group {8-20 Myrs,
10-50 pc away} , which provides a coeval sample of multiple spectral
types, and it has already produced two magnificent resolved debris
disks: AU Mic and Beta Pic. Such coeval sample will provide us with a
snapshop of the crucial time in disk evolution in which the disk makes
the transition from optically thick to optically thin, and it will be
useful to study the stellar mass dependence of the disk evolution.

ACS/HRC/WFC 10438

The Late Formation of Satellite Galaxies

Tiny isolated HII regions have been discovered up to 30 kpc from the
closest galaxy in the NOAO Survey for Ionization in Neutral Gas
Galaxies {SINGG}. These halo HII regions can be ionized by only a few
OB stars and seem to be most commonly found in interacting systems.
They may represent the beginning of the formation of satellite
galaxies at low redshift and/or are the source of the numerous
intracluster planetary nebula. The halo HII regions are a unique mode
of star formation in a low density and low metallicity environment and
high resolution HST images are required to identify their underlying
stellar populations. Determining the stellar populations of these HII
regions will establish whether in-situ star formation is a significant
contributor to the stellar content and enrichment of galactic halos
and intergalactic space. In particular, ACS/HRC observations are
required for their resolution, UV sensitivity, and wide wavelength
coverage, allowing young and intermediate age populations to be
identified. Parallel ACS/WFC observations will explore the possibility
of a further stellar population in the interactive debris. The results
of this project have implications on the formation of satellite
galaxies, the origin of Galactic halo B stars, IGM ionization and
enrichment, and star formation principles.

ACS/HRC/WFC 10389

ACS CCDs daily monitor - Cycle 13 - Part 2

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 program will be
for the entire lifetime of ACS.

FLIGHT OPERATIONS SUMMARY:

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

HSTARS:

9958 - GSacq(1,3,1) failed, search radius limit exceeded on FGS 1 @
266/20:59:42z At AOS the map showed errors of V1= 0.71, V2= -1.11, V3=
0.80, RSS= 1.54.

9959 - ACS Target Acquisition Failed due to Guide Star Acq Failure @
266/21:08:42z ACS target acquisition scheduled at 266/21:07:02 failed
due to GSacq failure.

9960 - GSAcq(1,2,1) failed to RGA Control (T2GAttHd) @ 268/12:45:43z
The GSAcq(1,2,1) scheduled at 268/12:45:43 - 12:53:47 failed to TGS
Submode T2GAttHd. Prior FHST OBAD1 (with maneuver) scheduled at
268/12:28:34 failed to remove error. OBAD Error showed V1= 65046.71,
V2=18460.56, V3=15521.12, (RSS)=69374.15 (arcsec). Prior FHST OBAD2
(with maneuver) scheduled at 268/12:41:13 showed vehicle axis errors:
V1=707.22, V2=-1949.78, V3=-116.41 (arcsec). 3-axis (RSS) value
=2077.34 (arcsec). OBAD using FHST MAP data from 2 FHST was unable to
bring attitude error within FGS search radius of 56 arcsec.

9961 - GSACQ(1,2,1) fails, excessive attitude error @ 269/06:32:08z
Upon AOS at 07:06:10, HST was in gyro control in M2G mode with no FGS
fine lock. GSACQ(1,2,1) at 06:32:08 occurred without telemetry, OBAD
error at 06:17:54 had total RSS error of 80374.52 arcseconds, second
OBAD at 06:27:09 had total RSS error of 2695.39 arc seconds, greater
than guide star search radius. Further information after engineering
recorder dump. Observations affected: ACS 17 to 21.

COMPLETED OPS REQUEST:
17545-0 - TRT Trending Test # 9 @ 266/1443z
17552-0 - Genslew for proposal 10487 - slot 10 @ 266/1842z
17551-0 - Genslew for proposal 10487 - slot 11 @ 266/1844z

COMPLETED OPS NOTES: (None)
SCHEDULED SUCCESSFUL FAILURE TIMES
FGS
Gsacq 20 19
266/20:59:42z (HSTAR # 9958)

FGS
Reacq 18 16
268/12:45:43z (HSTAR # 9960)
269/06:32:08z
(HSTAR # 9961)

OBAD with
Maneuver 74 72 268/12:31:28z (HSTAR
# 9960)
269/06:20:41z
(HSTAR # 9961)



SIGNIFICANT EVENTS:

FLASH REPORT: "TRT On-Orbit Test" (summary extract) (Fri, 23 Sep 2005
12:27, from Mike Wenz): "The FGS-2R TRT Trending test was successfully
executed on orbit today from 12:57 - 15:07.

FLASH REPORT: "FRR Flash Report: NICMOS CS 5.00 Installation (NV0009)"
(summary extract) (Fri, 23 Sep 2005 17:24, from Randy Jay Stevens):
"The Flight Readiness Review for the installation of NICMOS CS 5.00
FSW into EEPROM (NV0009) was held on September 23, 2005 in GSFC
building 3, S107A. Approval was given to proceed with the
installation. Commanding will begin on 269/12:45 (September 26, 8:45
am EST)."