Notice:
Due to the conversion of some ACS WFC or HRC observations into
WFPC2,
or NICMOS observations after the loss of ACS CCD science
capability
in January, there may be an occasional discrepancy between a
proposal's
listed (and correct) instrument usage and the abstract that
follows
it.
HUBBLE
SPACE TELESCOPE - Continuing to collect World Class Science
DAILY
REPORT # 4494
PERIOD
COVERED: UT November 26, 2007 (DOY 330)
OBSERVATIONS
SCHEDULED
ACS/SBC
10840
The
FUV fluxes of Tauri stars in the Taurus molecular cloud
Present
and forthcoming ground-based and space surveys of the T Tauri
stars
in the Taurus molecular cloud will provide information from high
energy
stellar and accretion radiation to low energy solid state and
molecular
emission from the disk, making those stars perfect
laboratories
to carry out self-consistent studies of disk physics and
evolution.
We propose to complete this wealth of information by
obtaining
ACS/FUV spectra for a significant sample of Taurus T Tauri
stars,
covering a range of accretion properties and dust evolutionary
stages.
FUV fluxes carry ~ 10 - 100 more energy than X-rays into these
disks
and are thus crucial gas heating agents and key to disk dispersal
by
photoevaporation. These observations are a pre-requisite to interpret
observations
with Spitzer, SOFIA, Herschel, and ALMA, and will become
one
of the important legacies of HST to the star formation community.
ACS/SBC
WFPC2 11175
UV
Imaging to Determine the Location of Residual Star Formation in
Galaxies
Recently Arrived on the Red Sequence
We
have identified a sample of low-redshift {z = 0.04 - 0.10} galaxies
that
are candidates for recent arrival on the red sequence. They have
red
optical colors indicative of old stellar populations, but blue
UV-optical
colors that could indicate the presence of a small quantity
of
continuing or very recent star formation. However, their spectra lack
the
emission lines that characterize star-forming galaxies. We propose
to use
ACS/SBC to obtain high- resolution imaging of the UV flux in
these
galaxies, in order to determine the spatial distribution of the
last
episode of star formation. WFPC2 imaging will provide B, V, and I
photometry
to measure the main stellar light distribution of the galaxy
for
comparison with the UV imaging, as well as to measure color
gradients
and the distribution of interstellar dust. This detailed
morphological
information will allow us to investigate the hypothesis
that
these galaxies have recently stopped forming stars and to compare
the
observed distribution of the last star formation with predictions
for
several different mechanisms that may quench star formation in
galaxies.
WFPC2
11024
WFPC2
CYCLE 15 INTERNAL MONITOR
This
calibration proposal is the Cycle 15 routine internal monitor for
WFPC2,
to be run weekly to monitor the health of the cameras. A variety
of
internal exposures are obtained in order to provide a monitor of the
integrity
of the CCD camera electronics in both bays {both gain 7 and
gain
15 -- to test stability of gains and bias levels}, a test for
quantum
efficiency in the CCDs, and a monitor for possible buildup of
contaminants
on the CCD windows. These also provide raw data for
generating
annual super-bias reference files for the calibration
pipeline.
FGS
11212
Filling
the Period Gap for Massive Binaries
The
current census of binaries among the massive O-type stars is
seriously
incomplete for systems in the period range from years to
millennia
because the radial velocity variations are too small and the
angular
separations too close for easy detection. Here we propose to
discover
binaries in this observational gap through a Faint Guidance
Sensor
SNAP survey of relatively bright targets listed in the Galactic O
Star
Catalog. Our primary goal is to determine the binary frequency
among
those in the cluster/association, field, and runaway groups. The
results
will help us assess the role of binaries in massive star
formation
and in the processes that lead to the ejection of massive
stars
from their natal clusters. The program will also lead to the
identification
of new, close binaries that will be targets of long term
spectroscopic
and high angular resolution observations to determine
their
masses and distances. The results will also be important for the
interpretation
of the spectra of suspected and newly identified binary
and
multiple systems.
FGS
11299
Calibrating
the Mass-Luminosity Relation at the End of the Main Sequence
We
propose to use HST-FGS1R to finish calibrating the mass-luminosity
relation
for stars less massive than 0.5 Msun, with special emphasis on
objects
near the stellar/substellar border. Our goals are to determine
Mv
values to 0.05 magnitude and masses to 5%, and thereby build the
fundamental
database of stellar masses that we will use to test
theoretical
models as never before. This program uses the combination of
HST-
FGS3/FGS1R at optical wavelengths, historical infrared speckle
data,
ground-based parallax work, metallicity studies, and radial
velocity
monitoring to examine nearby, subarcsecond binary systems. The
high
precision separation and position angle measurements with
HST-FGS3/FGS1R
{to 1 mas in the separations} for these faint {V = 10-15}
targets
simply cannot be equaled by any ground-based technique. As a
result
of these measurements, we are deriving high quality luminosities
and
masses for the components in the systems, and characterizing their
spectral
energy distributions from 0.5 to 2.2 microns. One of the
objects,
GJ 1245 C with mass 0.074 +/- 0.002 Msun, is the only object
known
with an accurate dynamical mass less than 0.10 Msun. The payoff of
this
proposal is high because the six systems selected for final
observations
in Cycles 15 and 16 have already been resolved during
Cycles
5-13 with HST FGS3/FGS1R and contain most of the reddest objects
for
which accurate dynamical masses can be determined.
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 DARKs. 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
10852
Coronagraphic
Polarimetry with NICMOS: Dust grain evolution in T Tauri
stars
The
formation of planetary systems is intimately linked to the dust
population
in circumstellar disks, thus understanding dust grain
evolution
is essential to advancing our understanding of how planets
form.
By combining {1} the coronagraphic polarimetry capabilities of
NICMOS,
{2} powerful 3-D radiative transfer codes, and {3} observations
of
objects known to span the Class II-III stellar evolutionary phases,
we
will gain crucial insight into dust grain growth. By observing
objects
representative of a known evolutionary sequence of YSOs, we will
be
able to investigate how the dust population evolves in size and
distribution
during the crucial transition from a star+disk system to a
system
containing planetesimals. When combine with our previous study on
dust
grain evolution in the Class I-II phase, the proposed study will
help
to establish the fundamental time scales for the depletion of
ISM-like
grains: the first step in understanding the transformation from
small
submicron sized dust grains, to large millimeter sized grains, and
untimely
to planetary bodies.
NIC2
11197
Sweeping
Away the Dust: Reliable Dark Energy with an Infrared Hubble
Diagram
We
propose building a high-z Hubble Diagram using type Ia supernovae
observed
in the infrared rest-frame J-band. The infrared has a number of
exceptional
properties. The effect of dust extinction is minimal,
reducing
a major systematic that may be biasing dark energy
measurements.
Also, recent work indicates that type Ia supernovae are
true
standard candles in the infrared meaning that our Hubble diagram
will
be resistant to possible evolution in the Phillip's relation over
cosmic
time. High signal-to-noise measurements of 16 type Ia events at
z~0.4
will be compared with an independent optical Hubble diagram from
the
ESSENCE project to test for a shift in the derived dark energy
equation
of state due to a systematic bias. In Cycle 15 we obtained
NICMOS
photometry of 8 ESSENCE supernovae and are awaiting template
observations
to place them on the IR Hubble diagram. Here we request
another
8 supernovae be studied in the final season of the ESSENCE
search.
Because of the bright sky background, H-band photometry of z~0.4
supernovae
is not feasible from the ground. Only the superb image
quality
and dark infrared sky seen by HST makes this test possible. This
experiment
may also lead to a better, more reliable way of mapping the
expansion
history of the universe with the Joint Dark Energy Mission.
WFPC2
10915
ACS
Nearby Galaxy Survey
Existing
HST observations of nearby galaxies comprise a sparse and
highly
non-uniform archive, making comprehensive comparative studies
among
galaxies essentially impossible. We propose to secure HST's
lasting
impact on the study of nearby galaxies by undertaking a
systematic,
complete, and carefully crafted imaging survey of ALL
galaxies
in the Local Universe outside the Local Group. The resulting
images
will allow unprecedented measurements of: {1} the star formation
history
{SFH} of a >100 Mpc^3 volume of the Universe with a time
resolution
of Delta[log{t}]=0.25; {2} correlations between spatially
resolved
SFHs and environment; {3} the structure and properties of thick
disks
and stellar halos; and {4} the color distributions, sizes, and
specific
frequencies of globular and disk clusters as a function of
galaxy
mass and environment. To reach these goals, we will use a
combination
of wide-field tiling and pointed deep imaging to obtain
uniform
data on all 72 galaxies within a volume-limited sample extending
to
~3.5 Mpc, with an extension to the M81 group. For each galaxy, the
wide-field
imaging will cover out to ~1.5 times the optical radius and
will
reach photometric depths of at least 2 magnitudes below the tip of
the
red giant branch throughout the limits of the survey volume. One
additional
deep pointing per galaxy will reach SNR~10 for red clump
stars,
sufficient to recover the ancient SFH from the color-magnitude
diagram.
This proposal will produce photometric information for ~100
million
stars {comparable to the number in the SDSS survey} and uniform
multi-
color images of half a square degree of sky. The resulting
archive
will establish the fundamental optical database for nearby
galaxies,
in preparation for the shift of high- resolution imaging to
the
near-infrared.
WFPC2
11070
WFPC2
CYCLE 15 Standard Darks - part II
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
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.
WFPC2
11128
Time
Scales Of Bulge Formation In Nearby Galaxies
Traditionally,
bulges are thought to fit well into galaxy formation
models
of hierarchical merging. However, it is now becoming well
established
that many bulges formed through internal, secular evolution
of
the disk rather than through mergers. We call these objects
pseudobulges.
Much is still unknown about pseudobulges, the most
pressing
questions being: How, exactly, do they build up their mass? How
long
does it take? And, how many exist? We are after an answer to these
questions.
If pseudobulges form and evolve over longer periods than the
time
between mergers, then a significant population of pseudobulges is
hard
to explain within current galaxy formation theories. A pseudobulge
indicates
that a galaxy has most likely not undergone a major merger
since
the formation of the disk. The ages of pseudobulges give us an
estimate
for the time scale of this quiescent evolution. We propose to
use
24 orbits of HST time to complete UBVIH imaging on a sample of 33
nearby
galaxies that we have observed with Spitzer in the mid-IR. These
data
will be used to measure spatially resolved stellar population
parameters
{mean stellar age, metallicity, and star formation history};
comparing
ages to star formation rates allows us to accurately constrain
the
time scale of pseudobulge formation. Our sample of bulges includes
both
pseudo- and classical bulges, and evenly samples barred and
unbarred
galaxies. Most of our sample is imaged, 13 have complete UBVIH
coverage;
we merely ask to complete missing observations so that we may
construct
a uniform sample for studying bulge formation. We also wish to
compare
the stellar population parameters to a variety of bulge and
global
galaxy properties including star formation rates, dynamics,
internal
bulge morphology, structure from bulge-disk decompositions, and
gas
content. Much of this data set is already or is being assembled.
This
will allow us to derive methods of pseudobulge identification that
can
be used to accurately count pseudobulges in large surveys. Aside
from
our own science goals, we will present this broad set of data to
the
community. Thus, we waive proprietary periods for all observations.
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.
FLIGHT
OPERATIONS SUMMARY:
Significant
Spacecraft Anomalies: (The following are preliminary reports
of
potential non-nominal performance that will be investigated.)
HSTARS:
11080
- OBAD Failed Identification At 01:00:51 received 486 ESB 1902
"OBAD Failed ID". OBAD #1 was successful and showed
values of: V1 -2.51,
V2 -6.15, V3 -0.79, RSS 6.69. OBAD #2 failed and showed values of:
V1
-155021.17, V2 127693.68, V3 -177590.52, RSS 268096.31. OBAD flag
mnemonics showed GOBSTAT=255 (Attitude Determination Error) and
GCHACL09=1 or a failed state. The GSAcq @ 01:04:49 was successful.
At
01:52:51 OBAD MAP showed values of: V1 -1.25, V2 -4.43, V3 4.90,
RSS
6.72.
COMPLETED
OPS REQUEST: (None)
COMPLETED
OPS NOTES: (None)
SCHEDULED
SUCCESSFUL
FGS
GSacq
09
09
FGS
REacq
03
03
OBAD
with Maneuver
24
23
SIGNIFICANT
EVENTS: (None)