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Old April 8th 04, 04:22 PM
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Default Daily 3587

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT # 3587

PERIOD COVERED: DOY 98

OBSERVATIONS SCHEDULED

ACS/HRC 9747

An Imaging Survey of the Statistical Frequency of Binaries Among
Exceptionally-Young Dynamical Families in the Main Asteroid Belt

We propose an ambitious SNAPSHOT program to determine the frequency of
binaries among two very young asteroid families in the Main Belt, with
potentially profound implications. These families {of C- and S-type}
have recently been discovered {Nesvorny et al. 2002, Nature 417, 720},
through dynamical modeling, to have been formed at 5.8 MY and 8.3 MY
ago in catastrophic impact events. This is the first time such
precise and young ages have been assigned to a family. Main-belt
binaries are almost certainly produced by collisions, and we would
expect a young family to have a significantly higher frequency of
binaries than the background, because they may not yet have been
destroyed by impact or longer-term gravitational instabilities. In
fact, one of the prime observables from such an event should be the
propensity for satellites. This is the best way that new numerical
models for binary production by collisions {motivated largely by our
ground-based discoveries of satellites among larger asteroids}, can be
validated and calibrated. We will also measure two control clusters,
one being an "old" family, and the other a collection of background
asteroids that do not have a family association, and further compare
with our determined value for the frequency of large main-belt
binaries {2%}. We request visits to 180 targets, using ACS/HRC.

ACS/HRC 9851

Host Galaxies of Reverberation-Mapped AGNs

We propose to obtain unsaturated ACS high-resolution images of all
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, which is necessary for accurate determination of the
relationship between the AGN continuum flux and the size of the broad
Balmer-line emitting region of AGNs. Because this relationship is used
to estimate black-hole masses of large samples of distant AGNs,
correct determination of the slope of this relationship is critically
important.

ACS/HRC/WFC 10044

ACS internal CTE monitor

The charge transfer efficiency {CTE} of the ACS CCD detectors will
decline as damage due to on-orbit radiation exposure accumulates. This
degradation will be closely monitored at regular intervals, because it
is likely to determine the useful lifetime of the CCDs. 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 10060

CCD Daily Monitor

This program consists of basic tests to monitor, the read noise, the
development of hot pixels and test for any source of noise in ACS CCD
detectors. This programme will be executed once a day for the entire
lifetime of ACS.

ACS/WFC 9717

Low Redshift Cluster Gravitational Lensing Survey

This proposal has two main scientific goals: to determine the dark
matter distribution of massive galaxy clusters, and to observe the
high redshift universe using these clusters as powerful cosmic
telescopes. Deep, g, r, i, z imaging of a sample of low-z {0.2-0.4}
clusters will yield a large sample of lensed background galaxies with
reliable photometric redshifts. By combining strong and weak lensing
constraints with the photometric redshift information it will be
possible to precisely measure the cluster dark matter distribution
with an unprecedented combination of high spatial resolution and area
coverage, avoiding many of the uncertainties which plague ground-based
studies and yielding definitive answers about the structure of massive
dark matter haloes. In addition, the cosmological parameters can be
constrained in a largely model independent way using the multiply
lensed objects due to the dependence of the Einsteinng radius on the
distance to the source. We can also expect to detect several highly
magnified dropout galaxies behind the clusters in the redshift ranges
4-5 5-6 and 7-8, corresponding to a drop in the flux in the g, r, and
i bands relative to longer wavelength. We will obtain the best
information to date on the giant arcs already known in these clusters,
making possible detailed, pixel-by-pixel studies of their star
formation rate, dust distribution and structural components, including
spiral arms, out to a redshift of around z~2.5 in several passbands.

ACS/WFC/WFPC2 9822

The COSMOS 2-Degree ACS Survey

We will undertake a 2 square degree imaging survey {Cosmic Evolution
Survey -- COSMOS} with ACS in the I {F814W} band of the VIMOS
equatorial field. This wide field survey is essential to understand
the interplay between Large Scale Structure {LSS} evolution and the
formation of galaxies, dark matter and AGNs and is the one region of
parameter space completely unexplored at present by HST. The
equatorial field was selected for its accessibility to all
ground-based telescopes and low IR background and because it will
eventually contain ~100, 000 galaxy spectra from the VLT-VIMOS
instrument. The imaging will detect over 2 million objects with I 27
mag {AB, 10 sigma}, over 35, 000 Lyman Break Galaxies {LBGs} and
extremely red galaxies out to z ~ 5. COSMOS is the only HST project
specifically designed to probe the formation and evolution of
structures ranging from galaxies up to Coma-size clusters in the epoch
of peak galaxy, AGN, star and cluster formation {z ~0.5 to 3}. The
size of the largest structures necessitate the 2 degree field. Our
team is committed to the assembly of several public ancillary datasets
including the optical spectra, deep XMM and VLA imaging, ground-based
optical/IR imaging, UV imaging from GALEX and IR data from SIRTF.
Combining the full-spectrum multiwavelength imaging and spectroscopic
coverage with ACS sub-kpc resolution, COSMOS will be Hubble's ultimate
legacy for understanding the evolution of both the visible and dark
universe.

FGS 9879

An Astrometric Calibration of the Cepheid Period-Luminosity Relation

We propose to measure the parallaxes of 10 Galactic Cepheid variables.
When these parallaxes {with 1-sigma precisions of 10% or better} are
added to our recent HST FGS parallax determination of delta Cep
{Benedict et al 2002}, we anticipate determining the Period-Luminosity
relation zero point with a 0.03 mag precision. In addition to
permitting the test of assumptions that enter into other Cepheid
distance determination techniques, this calibration will reintroduce
Galactic Cepheids as a fundamental step in the extragalactic distance
scale ladder. A Period-Luminosity relation derived from solar
metallicity Cepheids can be applied directly to extragalactic solar
metallicity Cepheids, removing the need to bridge with the Large
Magellanic Cloud and its associated metallicity complications.

NIC1/NIC2/NIC3 8792

NICMOS Post-SAA calibration - CR Persistence Part 3

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.

S/C 10097

NICMOS Temperature Setpoint Darks

NICMOS darks at different temperatures are needed to calibrate the
software tool used to create synthetic darks. Synthetic darks are used
during calibration. The temperatures of the NICMOS detectors will be
adjusted by +0.5 to -1.0 K from the nominal operating temperature.
Darks in each camera will be obtained at each of the temperature
settings. At the end of the Proposal the NCS nominal setpoint
temperature for the NICMOS detectors will be increased by 0.07 K for
the cool season {routine seasonal adjustment}.

STIS/CCD 10018

CCD Dark Monitor-Part 2

Monitor the darks for the STIS CCD.

STIS/CCD 10020

CCD Bias Monitor - Part 2

Monitor the bias in the 1x1, 1x2, 2x1, and 2x2 bin settings at gain=1,
and 1x1 at gain = 4, to build up high-S/N superbiases and track the
evolution of hot columns.

STIS/CCD 10037

STIS Cycle 12 Faint Standard Extension: FASTEX

WD 1657+343 is the faintest of four pure hydrogen WD stars that
comprised the original FASTEX program and has been observed thrice in
2000 and once in 2002 to firmly establish the absolute flux levels.
Annual revisits of one orbit should occur to monitor our predictions
of the CTE correction, which is increasing with time on orbit. G430L
at both the standard and E1 aperture position are required at the
exposure times already established as standard. The remaining time in
the orbit will be spent extending the wavelength coverage using G750L.
To date, HST has not provided any faint solar analog stars to
compliment the three V=12-13.5 mag solar analogs provided by M. Rieke
for NICMOS calibration. As instrumentation in space and on the ground
becomes more sensitive, fainter flux standards are required. A solar
analog in a field with low reddening is an excellent choice for a
fainter standard, because unreddened pure hydrogen WDs are rare beyond
V=16, because Solar absolute fluxes are well measured at all
wavelengths, and because the fluxes do not fall off as fast as the hot
WDs at longer wavelengths. A 16.5 G star may not be faint enough for
most JWST modes but will provide a significant step in the right
direction. The SNAP program requires such a spectrophotometric
standard, which lies at the bright limit of its spectroscopy mode.
NICMOS grism observation of this standard are planned for cycle 12 and
STIS spectra are required to establish the standard over the full
range from 0.3-2 microns.

WFPC2 10070

WFPC2 CYCLE 12 Supplemental Darks Part 2/3

This dark calibration program obtains 3 dark frames every day to
provide data for monitoring and characterizing the evolution of hot
pixels.

FLIGHT OPERATIONS SUMMARY:

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

HSTAR 9368: OTA SE review of PTAS processing logs for SA089O revealed
GS Reacquisition (1,2,1) @ 095/01:50Z that required two attempts
before FGS 2R was able to achieve FL-DV. Under investigation.

COMPLETED OPS REQs: None

OPS NOTES EXECUTED: None

SCHEDULED SUCCESSFUL FAILURE TIMES
FGS GSacq 9 9
FGS REacq 9 9
FHST Update 16 16
LOSS of LOCK

SIGNIFICANT EVENTS:

Set-up and Execution of HST ACS FSW 4.0 OAT scheduled 099/10:00Z -
100/04:00Z with GDOC, HITT, SE, and VEST using CCS "D" String with CCS
Release 5.0.3.1 and PRD O06400ST and CCS "C" with CCS Release 4.0.3.1
and PRD O06400T. The purpose of this testing is to verify the
installation and backout procedures for ACS FSW 4.0 in an operational
scenario.