Daily # 4235

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT # 4235

PERIOD COVERED: UT November 06, 2006 (DOY 310)

OBSERVATIONS SCHEDULED

ACS/HRC/WFC 10733

CCD Hot Pixel Annealing

Hot pixel annealing will continue to be performed once every 4 weeks.
The CCD TECs will be turned off and heaters will be activated to bring
the detector temperatures to about +20C. This state will be held for
approximately 6 hours, after which the heaters are turned off, the
TECs turned on, and the CCDs returned to normal operating condition.
To assess the effectiveness of the annealing, a bias and four dark
images will be taken before and after the annealing procedure for both
WFC and HRC. The HRC darks are taken in parallel with the WFC darks.
The charge transfer efficiency {CTE} of the ACS CCD detectors declines
as damage due to on-orbit radiation exposure accumulates. This
degradation has been closely monitored at regular intervals, because
it is likely to determine the useful lifetime of the CCDs. We combine
the annealling activity with the charge transfer efficiency monitoring
and also merge into the routine dark image collection. To this end,
the CTE monitoring exposures have been moved into this proposal . All
the data for this program is acquired using internal targets {lamps}
only, so all of the exposures should be taken during Earth occultation
time {but not during SAA passages}. This program emulates the ACS
pre-flight ground calibration and post-launch SMOV testing {program
8948}, so that results from each epoch can be directly compared.
Extended Pixel Edge Response {EPER} and First Pixel Response {FPR}
data will be obtained over a range of signal levels for both the Wide
Field Channel {WFC}, and the High Resolution Channel {HRC}.

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.

ACS/WFC 10824

Measuring the Shape and Orientation of the Galactic Dark-Matter Halo
using Hypervelocity Stars

We propose to obtain high-resolution images of five hypervelocity
stars in the Galactic halo in order to establish the first-epoch
astrometric frame for them, as a part of a long-term program to
measure precise proper motions. The origin of these recently
discovered stars, all with positive radial velocities above 540 km/s,
is consistent only with being ejected from the deep potential well of
the massive black hole at the Galactic center. The deviations of their
space motions from purely radial trajectories probe the departures
from spherical symmetry of the Galactic potential, mainly due to the
triaxiality of the dark-matter halo. Reconstructing the full
three-dimensional space motion of the hypervelocity stars, through
astrometric proper motions, provides a unique opportunity to measure
the shape and orientation of the dark halo. The hypervelocity stars
allow measurement of the potential up to 75 kpc from the center,
independently of and at larger distances than are afforded by tidal
streams of satellite galaxies such as the Sagittarius dSph galaxy.
HVS3 may be associated with the LMC, rather then the Galactic center,
and would therefore present a case for a supermassive black hole at
the center of the LMC. We request one orbit with ACS/WFC for each of
the five hypervelocity stars to establish their current positions
relative to background galaxies. We will request a repeated
observation of these stars in Cycle 17, which will conclusively
measure the astrometric proper motions.

ACS/WFC 10875

A Snapshot Survey of The Most Massive Clusters of Galaxies

We propose the continuation of our highly successful Cycle14 snapshot
survey of a sample of 123 very X-ray luminous clusters in the redshift
range 0.3-0.7. As demonstrated by the 21 snapshots obtained so far in
Cycle14 these systems frequently exhibit strong gravitational lensing
as well as spectacular examples of violent galaxy evolution. The
proposed observations will provide important constraints on the
cluster mass distributions, the physical nature of galaxy-galaxy and
galaxy-gas interactions in cluster cores, and a set of optically
bright, lensed galaxies for further 8-10m spectroscopy. Acknowledging
the broad community interest in this sample we waive our data rights
for these observations.

ACS/WFC 10880

The host galaxies of QSO2s: AGN feeding and evolution at high
luminosities

Now that the presence of supermassive black holes in the nuclei of
galaxies is a well established fact, other questions related to the
AGN phenomena still have to be answered. Problems of particular
interest are how the AGN gets fed, how the black hole evolves and how
the evolution of the black hole is related to the evolution of the
galaxy bulge. Here we propose to address some of these issues using
ACS/WFC + F775W snapshot images of 73 QSO2s with redshifts in the
range 0.3z0.4. These observations will be combined with similar
archival data of QSO1s and ground based data of Seyfert and normal
galaxies. First, we will intestigate whether interactions are the most
important feeding mechanism in high luminosity AGNs. This will be done
in a quantitative way, comparing the asymmetry indices of QSO2 hosts
with those of lower luminosity AGNs and normal galaxies. Second, we
will do a detailed study of the morphology of the host galaxies of
both QSO types, to determine if they are similar, or if there is an
evolutionary trend from QSO2s to QSO1s. The results from this project
will represent an important step in the understanding of AGN
evolution, and may also introduce a substantial modification to the
Unified Model.

ACS/WFC 10886

The Sloan Lens ACS Survey: Towards 100 New Strong Lenses

As a continuation of the highly successful Sloan Lens ACS {SLACS}
Survey for new strong gravitational lenses, we propose one orbit of
ACS-WFC F814W imaging for each of 50 high- probability strong
galaxy-galaxy lens candidates. These observations will confirm new
lens systems and permit immediate and accurate photometry, shape
measurement, and mass modeling of the lens galaxies. The lenses
delivered by the SLACS Survey all show extended source structure,
furnishing more constraints on the projected lens potential than
lensed-quasar image positions. In addition, SLACS lenses have lens
galaxies that are much brighter than their lensed sources,
facilitating detailed photometric and dynamical observation of the
former. When confirmed lenses from this proposal are combined with
lenses discovered by SLACS in Cycles 13 and 14, we expect the final
SLACS lens sample to number 80--100: an approximate doubling of the
number of known galaxy-scale strong gravitational lenses and an
order-of-magnitude increase in the number of optical Einstein rings.
By virtue of its homogeneous selection and sheer size, the SLACS
sample will allow an unprecedented exploration of the mass structure
of the early-type galaxy population as a function of all other
observable quantities. This new sample will be a valuable resource to
the astronomical community by enabling qualitatively new strong
lensing science, and as such we will waive all but a short {3-month}
proprietary period on the observations.

ACS/WFC 10905

The Dynamic State of the Dwarf Galaxy Rich Canes Venatici I Region

With accurate distances, the nearest groups of galaxies can be
resolved in 3 dimensions and the radial component of the motions of
galaxies due to local density perturbations can be distinquished from
cosmological expansion components. Currently, with the ACS, galaxy
distances within 8 Mpc can be measured effectively and efficiently by
detecting the tip of the red giant branch {TRGB}. Of four principal
groups at high galactic latitude in this domain, the Canes Venatici I
Group {a} is the least studied, {b} is the most populated, though
overwhelmingly by dwarf galaxies, and {c} is likely the least
dynamically evolved. It is speculated that galaxies in low mass groups
may fail to retain baryons as effectively as those in high mass
groups, resulting in significantly higher mass-to-light ratios. The
CVn I Group is suspected to lie in the mass regime where the
speculated astrophysical processes that affect baryon retention are
becoming important.

ACS/WFC/HRC 10920

High-Resolution Imaging of Nearby Lyman Break Galaxy Analogs in the
GALEX All-Sky Survey

We have used the ultraviolet all-sky imaging survey currently being
conducted by the Galaxy Evolution Explorer {GALEX} to identify for the
first time a rare population of low-redshift starbursts with
properties remarkably similar to high-redshift Lyman Break Galaxies.
These compact UV luminous galaxies {UVLGs} resemble Lyman Break
Galaxies in terms of size, UV luminosity, star-formation rate, surface
brightness, mass, metallicity, kinematics, dust content, and color.
They have characteristic ``ages'' {stellar mass/SFR} of only a few
hundred Myr. This population of galaxies is thus worthy of study in
its own right and as a sample of local analogs of Lyman Break
Galaxies. We propose to image a sample of the 9 nearest and brightest
compact UVLGs in the near-ultraviolet, near-infrared, and H-alpha
using ACS. With these images we will 1} characterize their structure
and morphology, 2} look for signs of interactions and mergers, 3}
investigate the distribution and propogation of star formation over
varying time scales, and 4} quantify the stellar populations and star
formation history, in order to determine whether a previous generation
of stars formed long before the current burst. These data will
perfectly complement our existing Spitzer, GALEX, and SDSS data, and
will provide important information on star-formation in the
present-day universe as well as shed light on the earliest major
episodes of star formation in high-redshift galaxies.

ACS/WFC/NIC2 10496

Decelerating and Dustfree: Efficient Dark Energy Studies with
Supernovae and Clusters

We propose a novel HST approach to obtain a dramatically more useful
"dust free" Type Ia supernovae {SNe Ia} dataset than available with
the previous GOODS searches. Moreover, this approach provides a
strikingly more efficient search-and-follow-up that is primarily pre-
scheduled. The resulting dark energy measurements do not share the
major systematic uncertainty at these redshifts, that of the
extinction correction with a prior. By targeting massive galaxy
clusters at z 1 we obtain a five-times higher efficiency in
detection of Type Ia supernovae in ellipticals, providing a
well-understood host galaxy environment. These same deep cluster
images then also yield fundamental calibrations required for future
weak lensing and Sunyaev-Zel'dovich measurements of dark energy, as
well as an entire program of cluster studies. The data will make
possible a factor of two improvement on supernova constraints on dark
energy time variation, and much larger improvement in systematic
uncertainty. They will provide both a cluster dataset and a SN Ia
dataset that will be a longstanding scientific resource.

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.

NIC2 10849

Imaging Scattered Light from Debris Disks Discovered by the Spitzer
Space Telescope around 21 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 {IR} emission with the Spitzer Space Telescope
as part of the Spitzer Legacy Science program titled "The Formation
and Evolution of Planetary Systems" {FEPS, P.I.: M.Meyer}. Modeling of
the thermal excess emission from the spectral energy distributions
alone cannot distinguish between narrowly confined high-opacity disks
and broadly distributed, low-opacity disks. By resolving light
scattered by the circumstellar material, our proposed NICMOS
observations can break this degeneracy, thus revealing the conditions
under which planet formation processes are occuring or have occured.
For three of our IR-excess stars that have known radial-velocity
planets, resolved imaging of the circumstellar debris disks may
further offer an unprecedented view of planet-disk interactions in an
extrasolar planetary system. Even non-detections of the light
scattered by the circumstellar material will place strong constraints
on the disk geometries, ruling out disk models with high optical
depth. Unlike previous disk imaging programs, our program contains a
well-defined sample of ~1 solar mass stars covering a range of ages
from 3 Myr to 3 Gyr, thus allowing us to study the evolution of disks
from primordial to debris for the first time. The results from our
program will greatly improve our understanding of the architecture of
debris disks around Sun-like stars, and will create a morphological
context for the existence of our own solar system. This proposal is
for a continuation of an approved Cycle 14 program {GO/10527, P.I.: D.
Hines}.

WFPC2 10748

WFPC2 CYCLE 14 Standard Darks

This dark calibration program obtains dark frames every week in order
to provide data for the ongoing calibration of the CCD dark current
rate, and to monitor and characterize the evolution of hot pixels.
Over an extended period these data will also provide a monitor of
radiation damage to the CCDs.

WFPC2/ACS/HRC/WFPC 11020

Cycle 15 Focus Monitor

The focus of HST is measured primarily with ACS/HRC over full CVZ
orbits to obtain accurate mean focus values via a well sampled
breathing curve. Coma and astigmatism are also determined from the
same data in order to further understand orbital effects on image
quality and optical alignments. To monitor the stability of ACS to
WFPC2 relative focii, we've carried over from previous focus monitor
programs parallel observations taken with the two cameras at suitable
orientations of previously observed targets, and interspersed them
with the HRC CVZ visits.

FLIGHT OPERATIONS SUMMARY:

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

HSTARS:

10497 - GSAcq (2,1,2) failed to RGA control due to Scan Step Limit
Exceeded on FGS 2

At AOS (310/21:06:19) GSAcq (2,1,2), scheduled 310/20:13:22-20:20:51
had failed to RGA control due to Scan Step Limit Exceeded on FGS 2.
OBAD MAP RSS value = 11.40 a-s.

COMPLETED OPS REQUEST: (None)

COMPLETED OPS NOTES: (None)

SCHEDULED SUCCESSFUL
FGS GSacq 12 11
FGS REacq 02 02
OBAD with Maneuver 24 24

SIGNIFICANT EVENTS: (None)