Status Report

NASA Hubble Space Telescope Daily Report # 3614

By SpaceRef Editor
May 18, 2004
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HUBBLE SPACE TELESCOPE – Continuing to collect World Class Science




ACS/HRC 10050

ACS Earth Flats

High signal 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 used by the pipeline and will provide
a comparison with flats derived via other techniques: L-flats from
stellar observations, sky flats from stacked GO observations, and
internal flats using the calibration lamps. Weekly coronographic
monitoring is required to assess the changing position of the spots.

ACS/HRC 9862

ACS detection of sub-stellar companions around Vega, Fomalhaut and
beta Pic via parallax & proper motion

The first visible light coronagraph on HST provides contrast ratios
near very bright stars that are unparalleled by ground-based
observations. Vega, Fomalhaut and Beta Pictoris have dusty debris
disks with structure thought to originate from the presence of
yet-undetected, substellar companions. The detection of substellar
companions is possible with the ACS HRC coronagraph if observations
are made in two epochs. Here we propose to image Vega in two epochs
within Cycle 12. We argue that in a few months interval, the sky plane
motion of any companions due to parallax and proper motion is large
relative to the HRC astrometric uncertainties. Likewise, we propose to
obtain a second epoch image of Beta Pic and Fomalhaut within Cycle 12
to complement the single epoch imaging of the GTO program. Because
Vega, Fomalhaut and Beta Pictoris are young and nearby, this imaging
campaign will be sensitive to brown dwarfs and massive extrasolar
giant planets at their predicted locations 40-60 AU projected radius
from each star. Either positive or negative results for each system
will be used to constrain the physical characteristics of massive
objects hypothesized to cause the observed disk asymmetries.


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.


Calibrating the Black Hole Mass Scale for Quasars

We propose to obtain ACS/WFC imaging of all 17 low-redshift quasars
that have black hole masses measured from reverberation mapping. This
is a key sample since all secondary methods to estimate black hole
mass in quasars depend on this local reverberation-mapped sample for
their calibration. The best external check on reverberation mapping is
whether it gives results that are consistent with the black hole mass-
host galaxy correlations of nearby galaxies. For local Seyfert
galaxies the reverberation masses appear consistent with the M-sigma
correlation, but it is not known whether this also holds true for
quasars because the stellar velocity dispersions of quasar hosts are
virtually impossible to measure. We will use the ACS data to measure
accurate bulge parameters {luminosity and effective radius} for the
host galaxies of the reverberation-mapped quasars. From the
fundamental plane or the Faber-Jackson relation, we can estimate the
host galaxy velocity dispersion and test whether the reverberation
masses follow the M-sigma relation even for objects with quasar
luminosities. This is a crucial test if we are to trust the
reverberation masses as the lowest rung on a "distance ladder" of
black hole mass estimators for quasars, so that quasars can be used to
trace the cosmological growth history of black holes. {Note added in
Phase II: the TAC awarded us 8 orbits to observe 7 quasars and a PSF

ACS/WFC 9727

Exploration of the SN Ia Hubble Diagram at z > 1.2

In the spirit of a Treasury proposal, we propose to organize, and
deliver to the astronomical community, non-proprietary follow-up
observations of ~10 Type Ia supernovae at 1<z<1.7 that are expected to
be discovered in a Cycle 12 Treasury proposal. Together with the
currently available sample, this would provide a Hubble diagram with
over 20 SNe Ia in this redshift range, where it is possible to test
the current cosmological model in the epoch of deceleration: If z ~
0.5 SNe Ia are fainter due to evolution rather than an accelerating
expansion, they should continue to get fainter at even higher
redshifts. This size sample will show trends and outliers, and permit
a more rigorous treatment of the asymmetric amplification distribution
from gravitational lensing. This is a key redshift range for the
studies of dark energy that will be done with future surveys; this
dataset will lay the ground-work for these studies by establishing the
simple properties of the supernovae in this redshift range, including
magnitudes, colors, and timescales. If considered more appropriate,
this proposal could be treated as a part of a Treasury or Director’s
Discretionary program, since the data would be available to everybody
immediately, and we would welcome others who would want to work with
us on it.


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

NIC/NIC3 9865

The NICMOS Parallel Observing Program

We propose to continue managing the NICMOS pure parallel program.
Based on our experience, we are well prepared to make optimal use of
the parallel opportunities. The improved sensitivity and efficiency of
our observations will substantially increase the number of
line-emitting galaxies detected. As our previous work has
demonstrated, the most frequently detected line is Halpha at
0.7<z<1.9, which provides an excellent measure of current star
formation rate. We will also detect star-forming and active galaxies
in other redshift ranges using other emission lines. The grism
observations will produce by far the best available Halpha luminosity
functions over the crucial–but poorly observed–redshift range where
galaxies appear to have assembled most of their stellar mass. This key
process of galaxy evolution needs to be studied with IR data; we found
that observations at shorter wavelengths appear to have missed a large
fraction of the star-formation in galaxies, due to dust reddening. We
will also obtain deep F110W and F160W images, to examine the space
densities and morphologies of faint red galaxies. In addition to
carrying out the public parallels, we will make the fully reduced and
calibrated images and spectra available on-line, with some
ground-based data for the deepest parallel fields included.

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.

NIC3 10337

The COSMOS 2-Degree ACS Survey NICMOS Parallels

The COSMOS 2-Degree ACS Survey NICMOS Parallels. This program is a
companion to program 10092.

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

STIS/MA1 10034

Cycle 12 MAMA Dark Monitor

This test performs the routine monitoring of the MAMA detector dark
noise. This proposal will provide the primary means of checking on
health of the MAMA detectors systems through frequent monitoring of
the background count rate. The purpose is to look for evidence of
change in dark indicative of detector problem developing.

WFPC2 10068

WFPC2 CYCLE 12 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.

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

WFPC2 10072


This calibration proposal is the Cycle 12 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
{gain 7 and gain 15}, a test for quantum efficiency in the CCDs, and a
monitor for possible buildup of contaminants on the CCD windows.


Significant Spacecraft Anomalies: (The following are preliminary
reports of potential non-nominal performance that will be
investigated.) None


1234-0 – TDW Cross-support tracking (T77 CODE) @ 138/1749z, 138/1937z,
138/2121z, 139/0403z

                         SCHEDULED     SUCCESSFUL    FAILURE TIMES
GSacq              9                            9
FGS REacq              7                            7
FHST Update           11                          11

SpaceRef staff editor.