Daily Report #4756

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT****** #4756

PERIOD COVERED: 5am December 12 - 5am December 15, 2008 (DOY
*************************** 347/1000z-350/1000z)

OBSERVATIONS SCHEDULED

WFPC2 11962

A New Supernova in the Antennae; Narrowing in on the Hubble Constant
and Dark Energy

A measurement of the Hubble constant to a precision of a few percent
would be a powerful aid to the investigation of the nature of dark
energy and a potent "end-to-end" test of the present cosmological
model. In Cycle 15 we constructed a new, streamlined distance ladder
utilizing high-quality type Ia supernova data and observations of
Cepheids with HST in the near-IR to minimize the dominant sources of
systematic uncertainty in past measurements of the Hubble constant and
reduce its total uncertainty to a little under 5%. Here we propose to
exploit this new route with a rare opportunity to begin reducing the
remaining uncertainty. SN 2007sr in the Antennae (NGC 4038/9) is the
rare SN Ia which is suitable for increasing the precision of small
calibration sample of SNe Ia. Even rarer is that it is close enough
that it's Cepheids are within range of observing with WFPC2 (and
NICMOS, should it return to life). But we need to act fast as the
window of long visibility and fixed orient runs from mid-early
December 2008 to early March 2009. We request 34 orbits with WFPC2 to
find the Cepheids in the SN host. We also request 16 orbits to observe
the Cepheids we find with Camera 2, F160W if NICMOS becomes available
by April 2009 . (If NICMOS does not return we would forgo these
observations and ask the TTRB to let us make them with our own WFC3-IR
allocation, though we much prefer the smaller pixel size of NIC2).

FGS 11943

Binaries at the Extremes of the H-R Diagram

We propose to use HST/Fine Guidance Sensor 1r to survey for binaries
among some of the most massive, least massive, and oldest stars in our
part of the Galaxy. FGS allows us to spatially resolve binary systems
that are too faint for ground-based, speckle or optical long baseline
interferometry, and too close to resolve with AO. We propose a
SNAP-style program of single orbit FGS TRANS mode observations of very
massive stars in the cluster NGC 3603, luminous blue variables, nearby
low mass main sequence stars, cool subdwarf stars, and white dwarfs.
These observations will help us to (1) identify systems suitable for
followup studies for mass determination, (2) study the role of
binaries in stellar birth and in advanced evolutionary states, (3)
explore the fundamental properties of stars near the main
sequence-brown dwarf boundary, (4) understand the role of binaries for
X-ray bright systems, (5) find binaries among ancient and nearby
subdwarf stars, and (6) help calibrate the white dwarf mass - radius
relation.

FGS 11942

Increasing the Accuracy of HST Astrometry with FGS1R

We propose to observe six exoplanetary system host stars and two
planetary nebulae central stars with FGS1r. All objects have been
previously observed under proposals GO-09233, -09969, -10989, and
-11210. These observations will significantly extend the time
baseline, permitting improvements in the determination of proper
motion. This systematic motion must be removed to get at the
perturbation of interest, either due to exoplanetary companions or the
orbital motion of the Earth (parallax). In most cases the perturbation
orbits will also improve. We improve either companion mass or PN
parallax. For one target, GJ 876, theoretical dynamical modelers have
proposed an inclination closer to 50 degrees, while FGS3 measurements
indicated an inclination closer to 84 degrees. These new data, once
combined with our older FGS3 data, will permit an independent
remeasurement of the inclination of the outermost companion, and a
re-evaluation of widely used dynamical algorithms.

FGS 11870

Calibrating FGS1R's Optical Field Angle Distortion (OFAD), Second
Epoch

This proposal gathers the data needed to calibrate the optical field
angle distortions in FGS1r to the level of accuracy required for
astrometry science. Selected stars from the galactic cluster M35 are
repeatedly observed in POSITION mode by FGS1r with F583W filter at a
variety of spacecraft pointings and telescope roll angles. Ideally the
observations are to occur at a time when this ecliptic star field is
near the anti-sun direction so that HST's roll angle is unconstrained.
Unfortunately this is not possible under two gyro operations.
Therefore, the observations in this proposal are somewhat very
constrained in roll. However, this test should suffice as an adequate
update to the original FGS1r OFAD that executed in December 2000. For
each visit, the desired telescope pointing is specified by POS TARG
and ORIENT special requirements.

WFPC2 11289

SL2S: The Strong Lensing Legacy Survey

Recent systematic surveys of strong galaxy-galaxy lenses {CLASS,
SLACS, GOODS, etc.} are producing spectacular results for galaxy
masses roughly below a transition mass M~10^13 Mo. The observed lens
properties and their evolution up to z~0.2, consistent with numerical
simulations, can be described by isothermal elliptical potentials. In
contrast, modeling of giant arcs in X-ray luminous clusters {halo
masses M ~10^13 Mo} favors NFW mass profiles, suggesting that dark
matter halos are not significantly affected by baryon cooling. Until
recently, lensing surveys were neither deep nor extended enough to
probe the intermediate mass density regime, which is fundamental for
understanding the assembly of structures. The CFHT Legacy Survey now
covers 125 square degrees, and thus offers a large reservoir of strong
lenses probing a large range of mass densities up to z~1. We have
extracted a list of 150 strong lenses using the most recent CFHTLS
data release via automated procedures. Following our first SNAPSHOT
proposal in cycle 15, we propose to continue the Hubble follow-up
targeting a larger list of 130 lensing candidates. These are
intermediate mass range candidates {between galaxies and clusters}
that are selected in the redshift range of 0.2-1 with no a priori
X-ray selection. The HST resolution is necessary for confirming the
lensing candidates, accurate modeling of the lenses, and probing the
total mass concentration in galaxy groups up to z~1 with the largest
unbiased sample available to date.

FGS 11213

Distances to Eclipsing M Dwarf Binaries

We propose HST FGS observations to measure accurate distances of 5
nearby M dwarf eclipsing binary systems, from which model-independent
luminosities can be calculated. These objects have either poor or no
existing parallax measurements. FGS parallax determinations for these
systems, with their existing dynamic masses determined to better than
0.5%, would serve as model-independent anchor points for the low-mass
end of the mass-luminosity diagram.

WFPC2 11130

AGNs with Intermediate-mass Black Holes: Testing the Black Hole-Bulge
Paradigm, Part II

The recent progress in the study of central black holes in galactic
nuclei has led to a general consensus that supermassive {10^6-10^9
solar mass} black holes are closely connected with the formation and
evolutionary history of large galaxies, especially their bulge
component. Two outstanding issues, however, remain unresolved. Can
central black holes form in the absence of a bulge? And does the mass
function of central black holes extend below 10^6 solar masses?
Intermediate-mass black holes {10^6 solar masses}, if they exist, may
offer important clues to the nature of the seeds of supermassive black
holes. Using the SDSS, our group has successfully uncovered a new
population of AGNs with intermediate-mass black holes that reside in
low-luminosity galaxies. However, very little is known about the
detailed morphologies or structural parameters of the host galaxies
themselves, including the crucial question of whether they have bulges
or not. Surprisingly, the majority of the targets of our Cycle 14
pilot program have structural properties similar to dwarf elliptical
galaxies. The statistics from this initial study, however, are really
too sparse to reach definitive conclusions on this important new class
of black holes. We wish to extend this study to a larger sample, by
using the Snapshot mode to obtain WFPC2 F814W images from a parent
sample of 175 AGNs with intermediate- mass black holes selected from
our final SDSS search. We are particularly keen to determine whether
the hosts contain bulges, and if so, how the fundamental plane
properties of the host depend on the mass of their central black
holes. We will also investigate the environment of this unique class
of AGNs.

WFPC2 11103

A Snapshot Survey of The Most Massive Clusters of Galaxies

We propose the continuation of our highly successful SNAPshot survey
of a sample of 125 very X-ray luminous clusters in the redshift range
0.3-0.7. As demonstrated by the 25 snapshots obtained so far in
Cycle14 and Cycle15 these systems frequently exhibit strong
gravitational lensing as well as spectacular examples of violent
galaxy interactions. 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.
All of our primary science goals require only the detection and
characterization of high-surface-brightness features and are thus
achievable even at the reduced sensitivity of WFPC2. Because of their
high redshift and thus compact angular scale our target clusters are
less adversely affected by the smaller field of view of WFPC2 than
more nearby systems. Acknowledging the broad community interest in
this sample we waive our data rights for these observations. Due to a
clerical error at STScI our approved Cycle15 SNAP program was barred
from execution for 3 months and only 6 observations have been
performed to date - reinstating this SNAP at Cycle16 priority is of
paramount importance to reach meaningful statistics.

FLIGHT OPERATIONS SUMMARY:

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

HSTARS:

11604 - GSAcq(2,3,2) failed due to QF2STOPF flag on FGS-2

At 347/08:40:36 GSAcq (2,3,2) scheduled from 08:36:52 - 08:44:10
failed due to QF2STOPF flag on FGS-2.

Observation affected: Astrometry Proposal ID 11943

11605 - GSACQ(2,3,2) failed, Search Radius Limit exceeded on FGS 2

GSACQ(2,3,2) at 347/13:21:26 failed to RGA control with Search Radius
Limit exceeded on FGS 2 at 13:28:01.

Observations affected: Astrometry, proposal ID 11943.

11607 - GSAcq(2,3,3) failed to RGA Hold (Gyro Control)

Upon acquisition of signal at 349/13:45:16, the GSAcq(2,3,3) scheduled
at 349/13:19:23 - 13:27:28 had failed to RGA Hold due to (QF2STOPF)
stop indication flag set on FGS-2.

Observation affected: Astrometry, Proposal ID 11942.

11608 - GSAcq(2,3,3) failed to RGA Hold (Gyro Control)

Upon acquisition of signal at 349/15:22:15, the GSAcq(2,3,3) scheduled
at 349/14:55:16 - 15:03:21 had failed to RGA Hold due to (QF2STOPF)
stop indication flag set on FGS-2.

Observations affected: Astrometry, Proposal ID 11942.

11609 - GSAcq(2,3,3) failed to RGA Hold (Gyro Control)

GSAcq(2,3,3) scheduled at 349/18:07:02 - 18:15:07 failed to RGA Hold
due to (QF2STOPF) stop flag indication on FGS-2.

Observations affected: Astrometry, Proposal ID 11942.

11610 - GSAcq(2,3,3) failed to RGA Hold (Gyro Control)

GSAcq(2,3,3) scheduled at 349/19:42:55 - 19:51:00 failed to RGA Hold
due to (QF2STOPF) stop flag indication on FGS-2.

Observations affected: Astrometry, Proposal ID 11942.

11611 - GSAcq(2,3,3) failed to RGA Hold (Gyro Control)

GSAcq(2,3,3) scheduled at 349/21:18:49 - 21:26:54 failed to RGA Hold
due to (QF2STOPF) stop flag indication on FGS-2.

Observations affected: Astrometry, Proposal ID 11942.

COMPLETED OPS REQUEST: (None)

COMPLETED OPS NOTES: (None)

********************** SCHEDULED***** SUCCESSFUL

FGS GSacq************** 29**************** 22
FGS REacq************** 06**************** 06
OBAD with Maneuver **** 70**************** 68

SIGNIFICANT EVENTS: (None)