Status Report

NASA Hubble Space Telescope Daily Report # 3479

By SpaceRef Editor
October 31, 2003
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HUBBLE SPACE TELESCOPE

DAILY REPORT # 3479

PERIOD COVERED: DOY 302

OBSERVATIONS SCHEDULED

ACS 9984

Cosmic Shear With ACS Pure Parallels

Small distortions in the shapes of background galaxies by foreground
mass provide a powerful method of directly measuring the amount and
distribution of dark matter. Several groups have recently detected
this weak lensing by large-scale structure, also called cosmic shear.
The high resolution and sensitivity of HST/ACS provide a unique
opportunity to measure cosmic shear accurately on small scales. Using
260 parallel orbits in Sloan textiti {F775W} we will measure for the
first time: beginlistosetlength sep0cm setlengthemsep0cm setlength
opsep0cm em the cosmic shear variance on scales <0.7 arcmin, em the
skewness of the shear distribution, and em the magnification effect.
endlist Our measurements will determine the amplitude of the mass
power spectrum sigma_8Omega_m^0.5, with signal-to-noise {s/n} ~ 20,
and the mass density Omega_m with s/n=4. They will be done at small
angular scales where non-linear effects dominate the power spectrum,
providing a test of the gravitational instability paradigm for
structure formation. Measurements on these scales are not possible
from the ground, because of the systematic effects induced by PSF
smearing from seeing. Having many independent lines of sight reduces
the uncertainty due to cosmic variance, making parallel observations
ideal.

ACS/CCD/WFC 9978

The Ultra Deep Field with ACS

The ACS Ultra Deep Field {UDF} is a survey carried out by using
Director’s Discretionary time. The main science driver are galaxy
evolution and cosmology. The primary instrument is the Advanced Camera
for Surveys but WFPC2 and NICMOS will also be used in parallel. The
data will be made public. The UDF consists of a single ultra-deep
field {410 orbits in total} within the CDF-S GOODS area. The survey
will use four filters: F435W {55 orbits}, F606W {55 orbits}, F775W
{150 orbits}, and F850LP {150 orbits}. The F435W {B} and F606W {V}
exposures will be one magnitude deeper than the equivalent HDF
filters. The F775W {I} exposure will be 1.5 magnitude deeper than the
equivalent HDF exposure. The depth in F775W and F850LP is optimized
for searching very red objects – like z=6 galaxies – at the detection
limit of the F850LP image. The pointing will be RA{J2000}=3 32 40.0
and Decl.{J2000}=-27 48 00. These coordinates may change slightly due
to guide star availability and implementation issues. We will attempt
to include in the field both a spectroscopically confirmed z=5.8
galaxy and a spectroscopically confirmed type Ia SN at z=1.3. The
pointing avoids the gaps with the lowest effective exposure on the
Chandra ACIS image of CDFS. This basic structure of the survey
represents a consensus recommendation of a Scientific Advisory
Committee to the STScI Director Steven Beckwith. A local Working Group
is looking in detail at the implementation of the survey.

ACS/HRC/WFC 10042

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 9722

Life in the fast lane: The dark-matter distribution in the most
massive galaxy clusters in the Universe at z>0.5

We propose two-filter ACS observations of a complete sample of 12 very
X-ray luminous galaxy clusters at 0.5<z<0.7 as a cornerstone of a
comprehensive multi-wavelength study of the properties of the most
massive clusters in the universe. Our sample includes the famous
systems Cl0016+16 and MS0451-03; all other clusters are new
discoveries from the MACS survey. Being the counterparts of the
best-studied systems at lower and higher redshift and comprising ALL
massive clusters at 0.5<z<0.7 observable from Mauna Kea this sample
will become the ultimate reference for cluster studies at z>0.5. HST’s
unique capabilities will allow us to: 1} measure accurately the
clusters’ dark matter distribution on scales from tens to more than
500/h_50 kpc from observations of strong and weak gravitational
lensing, 2} use galaxy-galaxy lensing to measure the shape, extent,
and mass content of the dark-matter halos of both cluster and field
galaxies, and 3} study the color morphology of mergers and the star
formation history of galaxies in a high-density environment. The
proposed observations are complemented by Chandra observations of all
our targets {all 12 awarded, 11 executed to date} which provide
independent constraints on the dark matter and gas distribution in the
cluster cores, as well a by extensive groundbased observations of weak
lensing on yet larger scales, galaxy dynamics, and the SZ effect.

ACS/WFC 9821

The Second Parameter Effect in Metal-Rich Globular Clusters: A
Snapshot Study of NGC 6388

While it has long been known that at least one parameter besides the
metallicity, [Fe/H], determines the horizontal branch {HB} morphology
of Galactic globular clusters {GCs}, our ignorance as to the nature of
this second parameter {or parameters} has been a major stumbling block
in understanding the formation history and age of the GC system. The
hot HB populations recently discovered by HST in the metal-rich GCs
NGC 6388 and NGC 6441 provide a unique opportunity for unraveling this
second-parameter effect. Many different theories have been proposed to
explain the pronounced upward slope of the HBs in these GCs, including
stellar rotation, metallicity spread, and a dwarf galaxy origin. We
propose to test these theories by obtaining B, V, I time-series
photometry of the RR Lyrae variables in the core of NGC 6388 in order
to determine whether, as predicted, the pulsation periods are
unusually long due to a high HB luminosity. If confirmed, this would
argue against age or mass loss as the second parameter in NGC 6388
and, more generally, would have implications for the use of RR Lyrae
stars as standard candles for determining GC distances and ages. Light
curves will also be obtained for the crowded Population II Cepheids
near the core of NGC 6388, the most metal-rich GC, along with NGC
6441, known to contain such stars. We waive proprietary rights to any
data obtained.

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 9979

The Ultra Deep Field – NICMOS Parallels

This is a plan to manage the NICMOS pure parallels of the ACS Ultra
Deep Survey. We will obtain a mix of F110W and F160W images along
sight-lines within the mosaiced ACS fields of the CDF-S GOODS and GEMS
surveys, with these sight-lines enabling an examination of the space
density and morphologies of the reddest galaxies.

STIS 9786

The Next Generation Spectral Library

We propose to continue the Cycle 10 snapshot program to produce a Next
Generation Spectral Library of 600 stars for use in modeling the
integrated light of galaxies and clusters. This program is using the
low dispersion UV and optical gratings of STIS. The library will be
roughly equally divided among four metallicities, very low {[Fe/H] lt
-1.5}, low {[Fe/H] -1.5 to -0.5}, near-solar {[Fe/H] -0.3 to 0.1}, and
super-solar {[Fe/H] gt 0.2}, well-sampling the entire HR-diagram in
each bin. Such a library will surpass all extant compilations and have
lasting archival value, well into the Next Generation Space Telescope
era. Because of the universal utility and community-broad nature of
this venture, we waive the entire proprietary period.

STIS/CCD 10000

STIS Pure Parallel Imaging Program: Cycle 12

This is the default archival pure parallel program for STIS during
cycle 12.

STIS/CCD 10017

CCD Dark Monitor-Part 1

Monitor the darks for the STIS CCD.

STIS/CCD 10019

CCD Bias Monitor – Part 1

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/CCD 10022

STIS CCD Hot Pixel Annealing Cycle 12

The effectiveness of the CCD hot pixel annealing process is assessed
by measuring the dark current behavior before and after annealing and
by searching for any window contamination effects. In addition CTE
performance is examined by looking for traps in a low signal level
flat. Follows on from proposal 9612.

STIS/MA1/MA2 10039

Spectroscopic Sensitivity Workout: First-order modes

We will observe the primary flux standards G191B2B, GD71 and GD153,
obtaining first-order spectra in all L-modes {G191B2B only in the CCD
modes due to its high brightness in the UV}. By comparing observed and
model spectra, we will update calibration reference files describing
spectroscopic sensitivity {and CTE loss} as a function of time. On
visit of GD71 will be spent on verifying the recently derived CTE
formula for STIS Spectroscopic modes with the CCD, by stepping the
target along the slit {7 positions} with two {short} exposure times.
This will verify the results using the two-amplifier readout method,
and provide high-S/N data at low intensity levels and low background
level.

WFPC2 10069

WFPC2 CYCLE 12 Supplemental Darks, Part 1/3

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

WFPC2 9709

POMS Test Proposal: WFII parallel archive proposal

This is the generic target version of the WFPC2 Archival Pure Parallel
program. The program will be used to take parallel images of random
areas of the sky, following the recommendations of the 2002 Parallels
Working Group.

WFPC2 9980

The Ultra Deep Field – WFPC2 Parallels

The ACS Ultra Deep Field {UDF} is a survey carried out by using
Director’s Discretionary time. The main science drivers are galaxy
evolution and cosmology. The primary instrument is the Advanced Camera
for Surveys but WFPC2, NICMOS, and STIS will also be used in pure
parallel mode. The data will be made public. The UDF consists of a
single ultra-deep field {410 orbits in total} within the CDF-S GOODS
area. We request a modification of the default pure parallel programs.
Rather than duplicate the redder bands which will be done much better
with ACS, we propose to observe in the near-ultraviolet F300W filter.
These data will enable study of the rest-frame ultraviolet morphology
of galaxies at 0<z<1, allowing determination of the morphological
k-correction and the location of star formation within galaxies, using
a sample that is likely to be nearly complete with multi-wavelength
photometry and spectroscopic redshifts. The results can be used to
interpret observations of higher redshift galaxies by ACS.

FLIGHT OPERATIONS SUMMARY:

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

COMPLETED OPS REQs:
17056-0 – Off-line +D SPA @ 302/1412z

OPS NOTES EXECUTED:
1169-3 – Increase Batt Upper Temp Limit after Off-lining +D SPA @ 302/1414z
1160-2 – Default Configuration for TMDIAG’s @ 302/1501z

                           SCHEDULED     SUCCESSFUL    FAILURE TIMES
FGS GSacq                5                         5
FGS REacq                10                       10
FHST Update              14                       14
LOSS of LOCK

SIGNIFICANT EVENTS:

Successfully completed Off-lining Solar Array Section 1, +D SPA @
302/14:12Z (OR 17056 with attached IP-046 and COP 4.32). Opened +D
SPA Trim Relay and configured HST486 FSW to keep the +D SPA
permanently disconnected while EPS operates in Trim Relay Software
Charge Control (TRSWCC) mode. EPS SEs monitored power system
operations for two orbits to verify nominal operation of TRSWCC (+D
SPA Trim Relay remained disconnected, commanded relay order upon
Trickle Charge initiation). EPS SEs continued to monitor system
performance, especially battery temperatures and pressures, to assess
how this configuration change affects battery capacity.

SpaceRef staff editor.