Daily #4171

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT # 4171

PERIOD COVERED: UT August 4,5,6, 2006 (DOY 216,217,218)

OBSERVATIONS SCHEDULED


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/WFC 10911

Calibration of ACS F814W Surface Brightness Fluctuations

The surface brightness fluctuations {SBF} method has emerged as the
primary distance indicator for mapping local large-scale structures
{Virgo, Fornax}, as well as the velocity field out to nearly 15,000
km/s {z 0.05}. This is because other precision distance indicators
either lack the requisite depth {Cepheids, TRGB} or are too rare for
adequate sampling {supernovae}, while more traditional methods
{Tully-Fisher, fundamental plane} lack the necessary precision. The
SBF method is now being used with great success in several major ACS
Wide Field Camera programs. However, whereas the band of choice for
the nearby structure studies has been F850LP, for the distant
large-scale flow studies it is F814W because of its much greater
throughput. As a result, the current calibration for the more distant
studies is inadequate. We propose to establish the first systematic
calibration of the SBF method in the important F814W ACS WFC bandpass.
We will do this by measuring SBF in an optimized sample of galaxies in
the nearby compact Fornax cluster. Given the large amount of effort
and HST time being dedicated to F814W SBF measurements, it is
imperative that we correct this outstanding calibration problem while
time remains. For an extremely modest expenditure of orbits, we will
remove a significant systematic error and vastly improve the overall
accuracy of the ongoing ACS F814W SBF work. These data will also
greatly enhance the legacy value of the HST archive for future SBF
studies.

NIC2 10847

Coronagraphic Polarimetry of HST-Resolved Debris Disks

We propose to take full advantage of the recently commissioned
coronagraphic polarimetry modes of ACS and NICMOS to obtain imaging
polarimetry of circumstellar debris disks that were imaged previously
by the HST coronagraphs, but without the polarizers. It is well
established that stars form in gas-rich protostellar disks, and that
the planets of our solar system formed from a circum-solar disk.
However, the connection between the circumstellar disks that we
observe around other stars and the processes of planet formation is
still very uncertain. Mid-IR spectral studies have suggested that disk
grains are growing in the environments of young stellar objects during
the putative planet- formation epoch. Furthermore, structures revealed
in well resolved images of circumstellar disks suggest gravitational
influences on the disks from co-orbital bodies of planetary mass.
Unfortunately, existing imaging data provides only rudimentary
information abou the disk grains and their environments. Our proposed
observations, which can be obtained only with HST, will enable us to
quantitatively determine the sizes of the grains and optical depths as
functions of their location within the disks {i.e., detailed
tomography}. Armed with these well-determine physical and geometrical
systemic parameters, we will develop a set of self-consistent models
of disk structures to investigate possible interactions between unseen
planets and the disks from which they formed. Our results will also
calibrate models of the thermal emission from these disks, that will
in turn enable us to infer the properties of other debris disks that
cannot be spatially resolved with current or planned instruments and
telescopes.

ACS/HRC 10844

Following Eta Carinae's Change of State

Eta Carinae is now known to be undergoing some unusually rapid changes
on a timescale of several years. They are probably essential for
modeling the star's long-term recovery from its Giant Eruption 160
years ago -- the prototype "supernova impostor" event. Since high
spatial resolution is needed to isolate the central star, and the
present state will probably not recur in the future, it is important
to obtain HST data during the next two years. We propose a
cost-effective set of ACS observations with three goals: {1} to obtain
a continuing record of the star's rapid UV and visual brightening; {2}
to lengthen the temporal baseline of ACS images enough to settle an
important question concerning ejecta ages; and {3} to extend the
record of morphological changes in the inner ejecta past the midpoint
of eta Car's 5.5-year cycle.

NIC3 10839

The NICMOS Polarimetric Calibration

Recently, it has been shown that NICMOS possesses an instrumental
polarization at a level of 1.2%. This completely inhibits the data
reduction in a number of previous GO programs, and hampers the ability
of the instrument to perform high accuracy polarimetry. In all, 90
orbits of HST data are affected, with potentially many more in Cycle
15. We propose to obtain high signal to noise observations of three
polarimetric standards at the cardinal roll angles of the NICMOS
polarizers for both NIC1 and NIC2. These observations are designed to
fully characterize the instrumental polarization in order for NICMOS
to reach its full potential by enabling high accuracy polarimetry of
sources with polarizations around 1%. The residual polarization will
also be determined as a function of position and spectral energy
distribution. Our group will rapidly turn around the required data
products and produce reports and software for the accurate
representation of the instrumental polarization. These items will be
presented to STScI and for dissemination among the wider astronomical
community.

ACS/WFC 10829

Secular Evolution at the End of the Hubble Sequence

The bulgeless disk galaxies at the end of the Hubble Sequence evolve
at a glacial pace relative to their more violent, earlier-type
cousins. The causes of their internal, or secular evolution are
important because secular evolution represents the future fate of all
galaxies in our accelerating Universe and is a key ingredient to
understanding galaxy evolution in lower-density environments at
present. The rate of secular evolution is largely determined by the
stability of the cold ISM against collapse, star formation, and the
buildup of a central bulge. Key diagnostics of the ISM's stability are
the presence of compact molecular clouds and narrow dust lanes.
Surprisingly, edge-on, pure disk galaxies with circular velocities
below 120 km/s do not appear to contain such dust lanes. We propose to
obtain ACS/WFC F606W images of a well-selected sample of extremely
late-type disk galaxies to measure the characteristic scale size of
the cold ISM and determine if they possess the unstable, cold ISM
necessary to drive secular evolution. Our sample has been carefully
constructed to include disk galaxies above and below the critical
circular velocity of 120 km/s where the dust properties of edge-on
disks change so remarkably. We will then use surface brightness
profiles to search for nuclear star clusters and pseudobulges, which
are early indicators that secular evolution is at work, as well as
measure the pitch angle of the dust lanes as a function of radius to
estimate the central mass concentrations.

ACS/HRC 10800

Kuiper Belt Binaries: Probes of Early Solar System Evolution

Binaries in the Kuiper Belt are a scientific windfall: in them we have
relatively fragile test particles which can be used as tracers of the
early dynamical evolution of the outer Solar System. We propose to
continue a Snapshot program using the ACS/HRC that has a demonstrated
discovery potential an order of magnitude higher than the HST
observations that have already discovered the majority of known
transneptunian binaries. With this continuation we seek to reach the
original goals of this project: to accumulate a sufficiently large
sample in each of the distinct populations collected in the Kuiper
Belt to be able to measure, with statistical significance, how the
fraction of binaries varies as a function of their particular
dynamical paths into the Kuiper Belt. Today's Kuiper Belt bears the
imprints of the final stages of giant-planet building and migration;
binaries may offer some of the best preserved evidence of that
long-ago era.

ACS/HRC 10796

A SNAP Image of the Circumstellar Ejecta of AE And in M31

The "supernova impostor" or Luminous Blue Variable AE Andromedae in
M31 has a spectrum that more closely resembles eta Car than any other
known LBV, including the presence of anomalously strong and peculiar
Fe II emission. An early FOC ultraviolet image of AE And showed a
faint, fuzzy extension of the presumed stellar object. This may be
nebulosity from an earlier eruption, or a very nearby UV-bright star.
Possibly AE And is embedded in a bipolar nebula. In any case, 2-color
ACS/HRC imaging will show the nature of this object. The presence of
ejecta will be relevant to understanding the anomalous emission. If
nebulous, the shape and extent of the ejecta can provide information
on the wind geometry. An extended bipolar structure, similar to eta
Car, would be especially interesting as it may be a clue to the
mechanism of the more energetic giant eruptions.

ACS/HRC/WFC 10758

ACS CCDs daily monitor

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. Changes from cycle 13:- The default
gain for WFC is 2 e- /DN. As before bias frames will be collected for
both gain 1 and gain 2. Dark frames are acquired using the default
gain {2}. This program cover the period May, 31 2006- Oct, 1- 2006.
The first half of the program has a different proposal number: 10729.

NIC3 10728

Flats Stability

This calibration proposal is the Cycle 14 NICMOS flat field monitor
program. A series of camera 1, 2, & 3 flat fields will be obtained to
monitor the health of the cameras.

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.

ACS/WFC 10546

The filaments of NGC1275

The spectacular H-0alpha filaments stretching over 100 kpc around the
central galaxy in the nearby Perseus cluster of galaxies, NGC1275,
resemble those found around distant radio galaxies and some
protogalaxies. The origin and ionization of the filaments are poorly
understood and relate to heating and cooling processes in galaxy
formation and evolution. We propose here to image the filaments in
order to reveal their true small-scale structure and to search for
clumps of young stars along them. The observations will produce the
first deep high resolution images of the whole filament system and,
with our 1 Ms Chandra image, constrain both particle and photon
ionization models for its ionization and excitation.

NIC2/ACS/WFC/WFPC 10532 2 Kinematics and morphology of the most
massive field disk galaxies at z1

We propose to obtain 1 orbit NIC-2 images of a sample of the 15 most
massive galaxies found at $1 z 1.3$. These were culled from over
20, 000 Keck spectra collected as part of DEEP and are unique among
high redshift massive galaxy samples in being kinematically selected.
We intend to test whether these potentially very young galaxies are
likely precursors to massive local disks, assuming no further merging.
NIC-2 images provide rest-frame optical morphologies that will show
whether they are normal disky systems or instead more disturbed
looking objects with multiple subcomponents, mergers, peculiar
structure, etc. NIC-2 provides near-IR resolutions sufficient to
enable measurements of bulges and disks subcomponents. The near-IR
will fill a critical gap in the broad-band SED photometry of the
galaxy and its subcomponents to estimate mean stellar ages and stellar
masses and to assess whether old stellar bulges and disks are in place
at that time. Finally, this sample will yield the first statistically
significant results on the $z 1$ evolution of the Tully-Fisher
relation for massive galaxies. In addition, we propose parallel
observations with ACS WFC {V and I bands} and WFPC2 {I-band}. These
will target up to 700 galaxies at redshifts 0.7 ... 1.2 for which the
DEEP2 survey has obtained precision redshifts and high-resolution
kinematic data. The added HST morphology and color information will
allow a variety of detailed studies on dynamical, structural, and
photometric evolution of galaxies.

NIC2 10527

Imaging Scattered Light from Debris Disks Discovered by the Spitzer
Space Telescope Around 20 Sun-like Stars

We propose to use the high contrast capability of the NICMOS
coronagraph to image a sample of newly discovered circumstellar disks
associated with sun-like stars. These systems were identified by their
strong thermal infrared emission with the Spitzer Space Telescope as
part of the Spitzer Legacy Science program titled, "The Formation and
Evolution of Planetary Systems {FEPS}." Modelling of the thermal
excess emission in the form of spectral energy distributions alone
cannot distinguish between narrowly confined high opacity disks and
broadly distributed, low opacity disks. However, our proposed NICMOS
observations can, by imaging the light scattered from this material.
Even non- detections will place severe constraints on the disk
geometry, ruling out models with high optical depth. Unlike previous
disk imaging programs, our program contains a well defined sample of
solar mass stars covering a range of ages from ~10Myrs to a few Gyrs,
allowing us to study the evolution of disks from primordial to debris
for the first time. These results will greatly improve our
understanding of debris disks around Sun-like stars at stellar ages
nearly 10x older than any previous investigation. Thus we will have
fit a crucial piece into the puzzle concerning the formation and
evolution of our own solar system.

NIC3/ACS/WFC 10504

Characterizing the Sources Responsible for Cosmic Reionization

Our group has demonstrated the role that massive clusters, acting as
powerful cosmic lenses, can play in constraining the abundance and
properties of low-luminosity star- forming sources beyond z~6; such
sources are thought to be responsible for ending cosmic reionization.
The large magnification possible in the critical regions of well-
constrained clusters brings sources into view that lie at or beyond
the limits of conventional exposures such as the UDF, as well as those
in imaging surveys being undertaken with IRAC onboard Spitzer. We have
shown that the combination of HST and Spitzer is particularly
effective in delivering the physical properties of these distant
sources, constraining their mass, age and past star formation history.
Indirectly, we therefore gain a valuable glimpse to yet earlier
epochs. Recognizing the result {and limitations} of the UDF exposure,
we propose a systematic search through 6 lensing clusters with ACS and
NICMOS for further z~6-7 sources in conjunction with existing deep
IRAC data. Our survey will mitigate cosmic variance and extend the
search both to lower luminosities and, by virtue of the NICMOS/IRAC
combination, to higher redshift. The goal is to count and characterize
representative sources at z~6-10 and to delineate the redshift range
of activity for the planning of future observations.

ACS/WFC 10258

Tracing the Emergence of the Hubble Sequence Among the Most Luminous
and Massive Galaxies

There is mounting evidence that the redshift range 1 z 2 was an
important era when massive galaxies assembled their stellar content
and assumed their present--day morphologies. Despite extensive HST
imaging surveys, however, there is very little data in the optical
rest frame {i.e., observed near--infrared} on the morphologies of the
most luminous galaxies at these redshifts. We propose to image a
carefully selected set of 20 of the most luminous, K--band selected
GOODS galaxies at 1.3 z 2, using NICMOS camera 2. This offers
diffraction--limited, critically sampled imaging at 1.6 microns to
ensure the best angular resolution for comparison to ACS. The galaxies
are chosen to span a simple 4--fold parameter space of morphological
and spectral type, in order to provide the most information about the
variety of massive galaxy properties in this redshift range. We will
investigate the emergence of large scale--length disks, stable spiral
structure, mature bulges with red stellar populations, central bar
structures, the incidence of disturbed morphology, the existence {or
lack thereof} of blue ellipticals, and other questions that concern
the evolution and maturation of the brightest, largest, and most
massive ordinary galaxies in this critical redshift range.

FGS 10103

FGS Astrometry of a Star Hosting an Extrasolar Planet: The Mass of
Upsilon Andromedae d

We propose observations with HST/FGS to determine the astrometric
elements {perturbation orbit semimajor axis and inclination} produced
by the outermost extra-solar planet orbiting the F8V star Upsilon
Andromedae. These observations will permit us to determine the actual
mass of the planet by providing the presently unknown sin i factor
intrinsic to the radial velocity method which discovered this object.
An inclination, i = 30degrees, within the range of one very low
precision determination using reanalyzed HIPPARCOS intermediate data
products, would produce the observed radial velocity amplitude, K = 66
ms with a companion mass of ~8 M_Jupiter. Such a mass would induce in
Upsilon Andromedae a perturbation semi-major axis, Alpha = 0arcs0012,
easily within the reach of HST/FGS fringe tracking astrometry. The
proposed observations will yield a planetary mass, rather than, as
previous investigations have done, only suggest a planetary mass
companion.


FLIGHT OPERATIONS SUMMARY:

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

HSTARS:

10390 - GSACQ(2,1,1) failed @ 217/1030z

GSAcq (1,2,2) scheduled at 08:45:11-08:52:30 failed to acquire lock
RGA control with QF1STOPF and QSTOP flags set at 219.08:48:10. OBAD's
showed RSS values of 2442.68 & 15.70 respectively. OBAD MAP showed a
RSS value of 5.36.

COMPLETED OPS REQUEST:
17878-0 - Genslew for proposal 10828- slot 5 @ 216/1513z
17879-0 - Genslew for proposal 10828- slot 6 @ 216/1514z

COMPLETED OPS NOTES: (None)

SCHEDULED SUCCESSFUL
FGS GSacq 28 27
FGS REacq 16 16
OBAD with Maneuver 88 88


SIGNIFICANT EVENTS:

Battery 1 Capacity Test Final Flash Report

At approximately 2006/216 16:55 GMT (12:55 pm local), Battery 1 was
successfully commanded back on-line in FSW. The remaining commanding
of the Battery 1 Reconditioning script was completed at approximately
2006/216 17:20 GMT (1:20 pm local).

EPS SEs monitored the system for 2 orbits after restoring EPS to a
6-battery FSW configuration and observed that the FSW SOC vs
pressure-based SOC variance is ~24 AH. If this condition persists for
the next 2 orbits with the delta greater than 15 AH, per the
contingency plan, EPS SE will increase the SOC2 safemode limit by 5 AH
(from 152 AH to 157 AH). Nominal system performance was observed for
the rest of the EPS system. Battery temperatures are still cycling
within nominal limits with battery 5 the warmest at 3.90 DegC.