Daily Report #4151

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT # 4151

PERIOD COVERED: UT July 7,8,9, 2006 (DOY 188,189,190)

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/HRC 11005

Funcional test - MEB2 switch

This is a functional test to be executed after the switch to MEB2.

NIC2 10906

The Fundamental Plane of Massive Gas-Rich Mergers: II. The QUEST QSOs

We propose deep NICMOS H-band imaging of a carefully selected sample
of 23 local QSOs. This program is the last critical element of a
comprehensive investigation of the most luminous mergers in the nearby
universe, the ultraluminous infrared galaxies {ULIRGs} and the
quasars. This effort is called QUEST: Quasar / ULIRG Evolutionary
STudy. The high-resolution HST images of the QUEST QSOs will
complement an identical set of images on the ULIRG sample obtained
during Cycle 12, an extensive set of ground-based data that include
long-slit NIR spectra from a Large VLT Program, and a large set of
mid-infrared spectra from a Cycle 1 medium-size program with Spitzer.
This unique dataset will allow us to derive with unprecedented
precision structual, kinematic, and activity parameters for a large
unbiased sample of objects spanning the entire ULIRG/QSO luminosity
function. These data will refine the fundamental plane of massive
gas-rich mergers and enable us to answer the following quesitons: {1}
Do ultraluminous mergers form elliptical galaxies, and in particular,
giant ellipticals? {2} Do ULIRGs evolve into optical bright QSOs? The
results from this detailed study of massive mergers in the local
universe will be relevant to understanding the basic physical
processes involved in creating massive early-type host on the one
hand, and growing/feeding embedded massive black holes on the other,
in major galaxy mergers. This is an important question since 50% of
cosmic star formation at high-z and most of the big BHs appear to be
formed in this process.

NIC1 10879

A search for planetary-mass companions to the nearest L dwarfs -
completing the survey

We propose to extend the most sensitive survey yet undertaken for very
low-mass companions to ultracool dwarfs. We will use NICMOS to
complete imaging of an all-sky sample of 87 L dwarfs in 80 systems
within 20 parsecs of the Sun. The combination of infrared imaging and
proximity allows us to search for companions with mass ratios q0.25
at separations exceeding ~3 AU, while probing companions with q0.5 at
~1.5 AU separation. This resolution is crucial, since no ultracool
binaries are known in the field with separations exceeding 15 AU.
Fifty L dwarfs from the 20-parsec sample have high- resolution
imaging, primarily through our Cycle 13 HST proposal which identified
six new binaries, including an L/T system. Here, we propose to target
the remaining 30 dwarfs

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 10775

An ACS Survey of Galactic Globular Clusters

We propose to conduct an ACS/WFC imaging survey of Galactic globular
clusters. We will construct the most extensive and deepest set of
photometry and astrometry to-date for these systems reaching a main
sequence mass of ~0.2 solar mass with S/N = 10. We will combine these
data with archival WFPC2 and STIS images to determine proper motions
for the stars in our fields. The resultant cleaned cluster CMDs will
allow us to study a variety of scientific questions. These include
[but are not limited to] 1} the determination of cluster ages and
distances 2} the construction of main sequence mass functions and the
issue of mass segregation 3} the internal motions and dynamical
evolution of globular clusters, and 4} absolute cluster motions,
orbits, and the Milky Way gravitational potential. We anticipate that
the unique resource provided by the proposed treasury archive will
play a central role in the field of globular cluster studies for
decades, with a stature comparable to that of the Hubble Deep Field
for high redshift studies.

ACS/WFC 10760

Black Hole X-ray Novae in M31

We have been carring out a Chandra {GO+GTO} and HST {GO} program to
find Black Hole X-ray Nova {BHXN} and their optical counterparts in
M31 for several years. To date we have found 2 dozen BHXN and 3 HST
optical counterparts for these BHXN. Our results suggest a rather high
ratio of BH to neutron star {NS} binaries, or a high duty cycle for
the BHXN. We propose to continue this program, with the goal of
determining the orbital period distribution and duty cycles of these
BHXN. Current results yield 3 orbital periods and 2 upper limits. Our
proposed observations will ~double the total number of periods and
therefore yield sufficient numbers to make a first approximation of
the orbital period distribution. The orbital period distribution is
the fundamental observable parameter any binary stellar evolution
models must match, and the duty cycle is very poorly known but
directly influences the binary lifetime. M31 is the only galaxy in
which this extra-galactic study of BHXN is feasible.

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 10753

An Astrometric Calibration Field Near the Ecliptic Pole

This program will obtain deep ACS astrometry of a Large Magellanic
Cloud star field lying within the planned continuous viewing zone of
the James Webb Space Telescope, which extends to a 5 degree radius
from the Ecliptic pole. To allow a full astrometric solution to be
calculated, controlling for distortions within ACS that may be time
variable over periods of months to years, we will observe our target
field at two distinct roll angles separated by approximately 90
degrees. To help control for large scale distortions, we will "chop"
the observations in at least one roll angle, using offsets of order
one third the ACS field of view.

ACS/WFC 10742

Ramp Filter and Grism Zeroth Order Wavelengths

A calibration of ramp filters on the ACS is obtained through crossing
the ramp filters with the G800L grism in observations of the standard
star GD 153. The standard star is also observed through the F606W
filter and each ramp crossed with a wide-band filter to measure any
filter-wedge offset from the standard grism calibration produced by
crossing a ramp with the grism. The ramp filters chosen for this first
calibration are those which have been used most extensively by
observers during the past ACS cycles and can be usefully crossed with
the G800L grism.

ACS/HRC/WFC 10737

CCD Stability Monitor

This program will verify that the low frequency flat fielding, the
photometry, and the geometric distortion are stable in time and across
the field of view of the CCD detectors. A moderately crowded stellar
field in the cluster 47 Tuc is observed every three months with the
HRC {at the cluster core} and WFC {6' West of the cluster core} using
the full suite of broad and narrow band imaging filters. The positions
and magnitudes of objects will be used to monitor local and large
scale variations in the plate scale and the sensitivity of the
detectors and to derive an independent measure of the detector CTE. An
additional orbit is required to compare WFC observations taken at gain
1 with those taken at the new default gain 2.

ACS/WFC 10730

External CTE Monitor

Monitor CTE in Cycle 14 for WFC and HRC

ACS/WFC 10630

The Fine Structure of Elliptical Galaxies in Voids

Elliptical galaxies constitute a remarkably homogeneous class of
objects with a tight color- magnitude relation and a well-defined
Fundamental Plane. In spite of their bland and symmetrical morphology,
they are characterized by a wealth of structural features {such as
nuclear disks, dust lanes, shells, blue cores, etc.} which contain
important clues to their formation history. Little is known about how
and if these sub-structures vary as a function of environment; in
fact, due to the morphology density relation, our knowledge of
ellipticals is strongly biased towards overdense regions such as
clusters. But what of the fine structure of ellipticals in voids?
According to theoretical predictions, void galaxies should have
different merger histories than those in clusters, which may imply
that their fine structure also differs. We address these issues using
the exquisite angular resolution of HST/ACS to resolve sub-structures
in the most accurately classified sample, to date, of truly isolated
ellipticals, identified using the 2dFGRS.

ACS/WFC 10629

Are Field OB Stars Alone?

This SNAP program offers an inexpensive, simple program to search for
low-mass companions of field OB stars. Do field OB stars exist in true
isolation, as suggested by a recent Galactic study, or are they the
tip of the iceberg on a small cluster of low-mass stars as predicted
by the cluster mass function and stellar IMF? Short ACS/WFC V and I
observations proposed here may easily resolve this issue for field OB
stars in the Small Magellanic Cloud. Truly isolated OB stars represent
a theoretical challenge and variation from clusters, in mode of star
formation, and have important consequences for our understanding of
the field stellar population in galaxies. Small clusters around the
field OB stars, on the other hand, may confirm the universality of the
stellar clustering law and IMF.

ACS/WFC 10567

Securing the Faint-End Galaxy Luminosity Function with Surface
Brightness Fluctuation Distances

The history of the formation of galaxies must leave an imprint in the
properties of the mass function of collapsed objects and in it's
observational manifestation the luminosity function. At present the
faint end of the luminosity function of galaxies is poorly known.
Accurate knowledge of the luminosity function over the full range of
galaxy clustering scales would provide serious constraints on both
initial cosmological conditions and modulating astrophysical
processes. Wide field imaging surveys with large groundbased
telescopes now provide the capability to identify dwarf galaxy
candidates to very faint levels. However distances to these candidates
are needed to overcome the omnipresent problem of group membership
uncertainties and to establish the intrinsic properties of the faint
end of the luminosity function. Single orbit observations with HST ACS
can provide adequate distances via the surface brightness fluctuation
method for targets in this program, resulting in the best definition
ever of the luminosity function to M_R=-11 in a specific environment.

ACS/HRC 10542

Charting the Sparkling Star Formation in NGC346

New, stunning V, I images of the youngest and most massive star
forming region NGC 346, in the Small Magellanic Cloud, have been
recently obtained with the HST/ACS. They reveal a myriad of small
compact clusters: some are still embedded in dust, possibly connected
by gas and dust filaments. We also discover a rich population of
pre-main sequence low mass stars {~3 -0.6 Mo} mainly distributed in
the body of NGC 346 and in these compact clusters, which formed with
the central cluster {~5My ago}, but have not reached the main sequence
yet. The immediate question that emerges is: how did star formation
occur in this region? Is there evidence for an age spread among these
clusters, that could be indicative of sequential star formation? We
are, therefore, requesting an immediate follow up investigation with
the ACS/HRC to perform a comprehensive UV/U study of the ten largest
clusters identified in the NGC 346 region, with the objective of
determining, in combination with the already available deep V, I data,
their mass function, their upper mass cut-off, whether mass
segregation is present, whether there are age variations, and what is
the impact of the stellar feedback, with the final aim to establish
how star formation has occured and progressed in this low metallicity
environment.

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.

ACS/HRC 10516

Host Galaxies of Reverberation-Mapped AGNs

We propose to obtain unsaturated ACS high-resolution images of four
reverberation- mapped active galactic nuclei in order to remove the
point-like nuclear light from each image, thus yielding a
"nucleus-free" image of the host galaxy. This will allow investigation
of host galaxy properties: our particular interest is determination of
the host-galaxy starlight contribution to the reverberation-mapping
observations. This is necessary {1} for accurate determination of the
relationship between the AGN nuclear continuum flux and the size of
the broad Balmer-line emitting regions of AGNs, which is important
because this relationship is used in estimating black hole masses for
large samples of QSOs, and {2} for accurate determination of the
bolometric luminosity of the AGN proper. In a Cycle 12 SNAP program,
we obtained images of 14 of the 36 reverberation-mapped AGNs for this
purpose. This additional request is to complete this program through
observations of the four important remaining sources.

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 10494

Imaging the mass structure of distant lens galaxies

The surface brightness distribution of extended gravitationally lensed
arcs and Einstein rings contains super-resolved information about the
lensed object, and, more excitingly, about the smooth and clumpy mass
distribution of the lens galaxies. The source and lens information can
non-parametrically be separated, resulting in a direct
"gravitational-mass image" of the inner mass-distribution of
cosmologically-distant galaxies {Koopmans 2005}. With this goal in
mind, we propose deep HST ACS-F555W/F814W and NICMOS-F160W imaging of
15 gravitational-lens systems with spatially resolved lensed sources,
selected from the 17 new lens systems discovered by the Sloan Lens ACS
Survey {Bolton et al. 2004}. Each system has been selected from the
SDSS and confirmed in a time-efficient HST-ACS snapshot program
{cycle-13}; they show highly-magnified arcs or Einstein rings, lensed
by a massive early-type lens galaxy. High-fidelity multi-color HST
images are required {not delivered by the 420-sec snapshot images} to
isolate these lensed images {properly cleaned, dithered and
extinction-corrected} from the lens galaxy surface brightness
distribution, and apply our "gravitational-mass imaging" technique.
The sample of galaxy mass distributions - determined through this
method from the arcs and Einstein ring HST images - will be studied
to: {i} measure the smooth mass distribution of the lens galaxies
{Dark and luminous mass are separated using the HST images and the
stellar M/L values derived from a joint stellar-dynamical analysis of
each system}; {ii} quantify statistically and individually the
incidence of mass-substructure {with or without obvious luminous
counter-parts such as dwarf galaxies}. Since dark-matter substructure
should be considerably more prevalent at higher redshift, both results
provide a direct test of this prediction of the CDM hierarchical
structure-formation model.

ACS/HRC 10396

Star Clusters, Stellar Populations, and the Evolution of the Small
Magellanic Cloud

As the closest star forming dwarf galaxy, the SMC is the preferred
location for detailed studies of this extremely common class of
objects. We therefore propose to use the capabilities of ACS, which
provide an improvement by an order of magnitude over what is possible
with ground-based optical imaging surveys that are limited by
confusion anddepth, to measure key stellar population parameters in
the SMC from VI color- magnitude diagrams. Our program focuses on
regions where crowding makes HST essential and includes 7 star
clusters and 7 field star locations. We will measure accurate ages of
the clusters, test stellar evolution models, gain fiducial stellar
sequences to use in fitting the field stars, check the form of the
IMF, and substantially extend the study of RR Lyrae variables in the
key NGC121 SMC globular cluster. The field pointings will allow us to
reconstruct the star formation history, look for enhanced star
formation that is expected when the SMC interacts with the LMC and/or
Milky Way, and compare its main sequence luminosity {and mass}
functions with those of the Milky Way, LMC, and UMi dwarf spheroidal.
This proposal is part of a coordinated HST and ground-based study of
the stellar history and star formation processes in the SMC.

FLIGHT OPERATIONS SUMMARY:

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

HSTARS:

#10346 REacq(2,1,2 ) failed due to search radius limit exceeded @
188/1219z

The REacq(2,1,2)scheduled at 188/12:15:09 failed at 12:19:58 due to
search radius limit exceeded on FGS 2. OBAD2 at 12:10:03 showed errors
of V1=68.13, V2=37.63, V3=57.97, RSS=97.05. ESD a05 (FGS Coarse Track
failed - Search Radius Limit exceeded) was received. Observations
affected : ACS 19, ACS 20, NIC 43

#10347 OBAD Failed Identification (ESB 1902) @ 188/2320z

At 188/23:20:04 OBAD1 using FHST-1 and FHST-2 failed. One 486 ESB
message 1902 (OBAD Failed Identification) was received. OBAD1 had
(RSS) value of 130325.87 arcseconds. OBAD success flag (mnemonic
GCHACL09) returned to the "no success" state(a value of 1). OBAD2 at
188/23:30:39 was successful with (RSS) value of 28540.30 arcseconds.

#10348 REacq(1,3,3) Failed to RGA Control @ 188/2334z

The REacq(1,3,3) scheduled at 188/23:34:59 - 23:43:04 failed to RGA
Hold due to uncorrected attitude error per Ref HSTAR# 10347. There
were no FGSs indication flags. Prior GSacq using same star id was
successful. Possible Observations affected: ACS 38 thru 41.

#10349 GSAcq (2,1,2) failed due to search radius limit exceeded @
190/0631z

GSAcq (2,1,2) scheduled @ 190/06:28:12-06:35:45 failed due to search
radius limit exceeded on FGS 1. Received one 486 ESB message a05
(Exceeded SRL). OBAD #1: V1 -1811.83, V2 1880.49, V3 -2874.30, RSS
3883.37. OBAD #2: V1 -0.53, V2 5.56, V3 7.14, RSS 9.06. At AOS
(190/07:39:10) OBAD MAP scheduled @ 07:15:32 showed the following: V1
-55.71, V2 2400.79, V3 -29.66, RSS 2401.62. REAcq 2,1,2 scheduled at
190/08:03:38 failed to RGA hold due to stop flag on FGS-1. Possible
observations effected: ACS 101-131. OBAD MAP @ 08:51:27 = V1 -389.08,
V2 4988.63, V3 -3.54, RSS 5003.78

COMPLETED OPS REQUEST:
#17543-2 Dump OBAD tables after failed OBAD (Generic) @ 188/2326z

COMPLETED OPS NOTES: (None)

SCHEDULED SUCCESSFUL FAILURE TIMES
FGS GSacq 23 22 190/0631z (HSTAR 10349)
FGS REacq 30 27 188/1215z (HSTAR 10346)
188/2334z (HSTAR 10348)
190/0803z (HSTAR 10349)
OBAD with Maneuver 76 75 188/2320z (HSTAR 10347)

SIGNIFICANT EVENTS: (None)