Daily Report #4167

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT # 4167

PERIOD COVERED: UT July 31, 2006 (DOY 212)

OBSERVATIONS SCHEDULED


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 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 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/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.

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, ACS/WFC 10802

SHOES-Supernovae, HO, for the Equation of State of Dark energy

The present uncertainty in the value of the Hubble constant {resulting
in an uncertainty in Omega_M} and the paucity of Type Ia supernovae at
redshifts exceeding 1 are now the leading obstacles to determining the
nature of dark energy. We propose a single, integrated set of
observations for Cycle 15 that will provide a 40% improvement in
constraints on dark energy. This program will observe known Cepheids
in six reliable hosts of Type Ia supernovae with NICMOS, reducing the
uncertainty in H_0 by a factor of two because of the smaller
dispersion along the instability strip, the diminished extinction, and
the weaker metallicity dependence in the infrared. In parallel with
ACS, at the same time the NICMOS observations are underway, we will
discover and follow a sample of Type Ia supernovae at z 1. Together,
these measurements, along with prior constraints from WMAP, will
provide a great improvement in HST's ability to distinguish between a
static, cosmological constant and dynamical dark energy.

NIC2/ACS/WFC/WFPC2 10532

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.

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.

FLIGHT OPERATIONS SUMMARY:

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

HSTARS:

#10386 OBAD Failed Identification @ 213/06:07:06z

OBAD at 05:56:21 using FHST-1 and FHST-2 showed error corrections of
V1 = -64.66, V2 = 13978.37, V3 = -3.62, RSS = 13978.52 arcseconds.
Second OBAD at 06:04:16 showed error correction of V1 = -2.61, V2 =
0.26, V3 = 6.01, RSS = 6.56. OBAD success flag (mnemonic GCHACL09)
returned to the "no success" state (a value of 1) at 06:13:44.
REACQ(2,1,2) at 06:09:25 failed due to Search Radius Limit exceeded on
FGS 2 at 06:14:16. Ops Request 17543-2 was performed at 06:15 to dump
OBAD tables 369 and 370.

#10387 REACQ(2,1,2) fails, Search Radius Limit on FGS 2 @ 213/06:14:16z

REACQ(2,1,2) at 213/06:09:25 failed due to search radius limit
exceeded on FGS 2 at 06:14:16. OBAD at 06:04:16 failed as described in
HSTAR 10386. Observation affected: ACS 60.

COMPLETED OPS REQUEST:
#17877-0 Secondary Mirror Focus Move @ 212/1447z
#17543-2 Dump OBAD tables after failed OBAD (Generic) @ 213/0615z (HSTAR # 10386)


COMPLETED OPS NOTES: (None)

SCHEDULED SUCCESSFUL
FGS GSacq 09 09
FGS REacq 05 04
OBAD with Maneuver 28 27

SIGNIFICANT EVENTS:

Secondary Mirror Focus Move Completed Flash Report

The Secondary Mirror Move focus commanding was successfully completed
this morning at 14:47 All of the telemetry verified correctly and the
guide star acquisition following the mirror move was successful.