HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science
DAILY REPORT # 4237
PERIOD COVERED: UT November 08, 2006 (DOY 312)
OBSERVATIONS SCHEDULED
ACS/HRC 10556
Neutral Gas at Redshift z=0.5
Damped Lyman-alpha systems {DLAs} are used to track the bulk of the
neutral hydrogen gas in the Universe. Prior to HST UV spectroscopy,
they
could only be studied from the ground at redshifts z>1.65. However,
HST
has now permitted us to discover 41 DLAs at z<1.65 in our
previous
surveys. Follow up studies of these systems are providing a wealth
of
information about the evolution of the neutral gas phase component
of
the Universe. But one problem is that these 41 low-redshift systems
are
spread over a wide range of redshifts spanning nearly 70% of the age
of
the Universe. Consequently, past surveys for low-redshift DLAs have
not
been able to offer very good precision in any small redshift regime.
Here we propose an ACS-HRC- PR200L spectroscopic survey in the
redshift
interval z=[0.37, 0.7] which we estimate will permit us to discover
another 41 DLAs. This will not only allow us to double the number of
low-redshift DLAs, but it will also provide a relatively
high-precision
regime in the low-redshift Universe that can be used to anchor
evolutionary studies. Fortunately DLAs have high absorption
equivalent
width, so ACS-HRC-PR200L has high-enough resolution to perform this
proposed MgII-selected DLA survey.
ACS/HRC 10738
Earth Flats
Sky flats will be obtained by observing the bright Earth with the
HRC
and WFC. These observations will be used to verify the accuracy of
the
flats currently in the pipeline and to monitor any changes. Weekly
coronagraphic monitoring is required to assess the changing position
of
the spots.
ACS/HRC 10833
Host Galaxies of Reverberation Mapped AGNs
We propose to obtain unsaturated high-resolution images of 17
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 in estimating black
hole
masses for large samples of QSOs, and {2} for accurate determination
of
the bolometric luminosity of the AGN proper. Through observations in
Cycles 12 and 14, we have obtained or will obtain images of 18 of the
35
objects in the reverberation-mapping compilation of Peterson et al.
{2004}. These observations revealed that the host-galaxy
contribution,
even in the higher-luminosity AGNs, is higher than expected and that
all
of the reverberation-mapped AGNs will have to be observed, not just
the
lower-luminosity sources; each source is different, and each source
is
important. Therefore we request time to observe the 17 remaining
reverberation-mapped AGNs.
ACS/HRC 10883
Light Echoes for Type Ia Supernovae
We propose a SNAPshot survey of light echoes from highly extinct
SNIa.
The major science goal is to determine whether the dust causing the
reddening of SNIa is of circumstellar origin or interstellar origin.
We
plan to observe about 25 SNIa. These observations are relevant for
the
studies of SNIa progenitor systems and for extinction corrections
for
supernova cosmology.
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/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} data set 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 data set and a SN Ia
data set that will be a long standing scientific resource.
FGS 10927
The Weight-Watcher Program for Subdwarfs
We propose to use HST/FGS1r to measure five subdwarf spectroscopic
binaries to determine masses for the components. Their
metallicities,
[Fe/H], range from -0.5 to -2.5, and their projected minimum
separations
range from 9 to 24 mas. These binaries are resolvable with HST/FGS1r
but
not any ground-based technique. Currently, there are only two
subdwarf
systems having any mass measurements. The proposed work will boost
the
total number of subdwarf systems with masses from two to seven, and
allow us to construct the first mass-luminosity relation for low-
metallicity stars.
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 10847
Coronagraphic Polarimetry of HST-Resolved Debris Disks
We propose to take full advantage of the recently commissioned
coronagraphic polarimetry modes of ACS and NICMOS to obtain imaging
polarimetry of circumstellar debris disks that were imaged previously
by
the HST coronagraphs, but without the polarizers. It is well
established
that stars form in gas-rich protostellar disks, and that the planets
of
our solar system formed from a circum-solar disk. However, the
connection between the circumstellar disks that we observe around
other
stars and the processes of planet formation is still very uncertain.
Mid-IR spectral studies have suggested that disk grains are growing
in
the environments of young stellar objects during the putative
planet-formation epoch. Furthermore, structures revealed in well
resolved images of circumstellar disks suggest gravitational
influences
on the disks from co-orbital bodies of planetary mass.
Unfortunately,
existing imaging data provides only rudimentary information about
the
disk grains and their environments. Our proposed observations, which
can
be obtained only with HST, will enable us to quantitatively
determine
the sizes of the grains and optical depths as functions of their
location within the disks {i.e., detailed tomography}. Armed with
these
well-determine physical and geometrical systemic parameters, we will
develop a set of self-consistent models of disk structures to
investigate possible interactions between unseen planets and the
disks
from which they formed. Our results will also calibrate models of
the
thermal emission from these disks, that will in turn enable us to
infer
the properties of other debris disks that cannot be spatially
resolved
with current or planned instruments and telescopes.
NIC2 10856
Delayed Negative Feedback in the Super Star Clusters of SBS0335-052E
The critical unanswered question in calculations of galaxy formation
and
evolution is the degree of feedback from the formation of the first
massive stars on subsequent evolution. Even the sign of the term is
uncertain. Super Star Clusters give one very dramatic answer by
forming
several thousand O stars in a volume with a radius of only a few
parsecs. How can that many massive stars form in such a small volume
without immediate dissipation of all gas by the intense ionizing
radiation from the stars? SBS0335-052E has done this, not once but
at
least 6 times in a region of approximately 500 parsecs in size. It
has
also managed to do this with the third lowest metallicity of any
known
galaxy. The record lowest metallicity is held by its companion
SBS0335-
052W. These observations are designed to test one answer to this
enigma;
that all of the ionizing photons are absorbed within a few hundred AU
of
the stars that emit them. This delays the negative feedback from
photoionization and allows the formation of other stars in the
immediate
neighborhood who are oblivious to the massive stars nearby. This
scenario predicts that both molecular and ionized gas exist within
the
radius of the super star clusters and that their emission should be
spatially coincident. We propose to test this hypothesis with high
spatial resolution NICMOS camera 2 images in the hydrogen Pa alpha
and
molecular hydrogen {1-0} S{1} emission lines. Spatial coincidence of
the
emission regions will confirm that gas within the cluster is
shielded
from ionizing and dissociating photons and is capable of forming new
stars within this tiny region in spite of the presence of thousands
of
massive stars. The current burst of star formation was probably
triggered by interaction with the giant spiral galaxy NGC 1376. This
proposal contains parallel observations of this galaxy with the ACS
WFC.
Due to the intense interest in SBS0335-052 we waive all proprietary
rights. The observations will then immediately compliment
observations
by the Great Observatories, Spitzer and ground base observatories .
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.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are preliminary
reports
of potential non-nominal performance that will be investigated.)
HSTARS: (None)
COMPLETED OPS REQUEST:
#17951-1 T2G Init Ram Installation @ 313/00:40z
COMPLETED OPS NOTES: (None)
SCHEDULED SUCCESSFUL
FGS
GSacq
09
09
FGS
REacq
05
05
OBAD with
Maneuver
28
28
SIGNIFICANT EVENTS:
Flash Report - FSW T2gInit RAM Installation:
FSW
T2gInit Patch was successfully installed in HST486 RAM. The T2gInit
loads were
completed at 312/15:22:50z and the T2gInit Patch was activated
at
312/16:13:31z. After software activation, PCS SE monitored attitude
control
mode transitions and all executed successfully. DMS, FSW, and
Systems
Management also monitored telemetry during this period and
everything
was nominal. The post installation RAM memory dump was good @
313/00:40z
(7:40pm).
-Lynn
Lynn F. Bassford
CHAMP HST Missions Operations Manager
Lockheed Martin Technical Operations
GSFC PH#: 301-286-2876
Cell/Voice Mail: 240-603-4873 Text/Pager:
2406034873@messaging.sprintpcs.com
"The Hubble Space Telescope is the astronomical observatory and
key to unlocking the most cosmic mysteries of the past, present and
future." - 7/26/6
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