NASA Hubble Space Telescope Daily Report # 3365
HUBBLE SPACE TELESCOPE
DAILY REPORT # 3365
PERIOD COVERED: DOYs 136-138
OBSERVATIONS SCHEDULED
ACS 9472
A Snapshot Survey for Gravitational Lenses among z >= 4.0 Quasars
Over the last few years, the Sloan Digital Sky Survey has revolutionized
the
study of high-redshift quasars by discovering over 200 objects with
redshift
greater than 4.0, more than doubling the number known in this redshift
interval.
The sample includes eight of the ten highest redshift quasars known. We
propose
a snapshot imaging survey of a well-defined sample of 250 z > 4.0 quasars
in
order to find objects which are gravitationally lensed. Lensing models
including
magnification bias predict that at least 4% of quasars in a flux-limited
sample
at z > 4 will be multiply lensed. Therefore this survey should find of
order 10
lensed quasars at high redshift; only one gravitationally lensed quasar
is
currently known at z > 4. This survey will provide by far the best sample
to
date of high-redshift gravitational lenses. The observed fraction of
lenses can
put strong constraints on cosmological models, in particular on the
cosmological
constant Lambda. In addition, magnification bias can significantly bias
estimates of the luminosity function of quasars and the evolution
thereof; this
work will constrain how important an effect this is, and thereby give us
a
better understanding of the evolution of quasars and black holes at early
epochs, as well as constrain models for black hole formation.
ACS 9658
ACS Earth Flats
This program will obtain sequences of flat field images by observing the
bright
Earth. Several UV filters from the interim calibration program {9564}
require
additional exposures to obtain the required illumination. A few UV
filters from
this program will be repeated to monitor for changes in the flat fields
and to
verify the interim results. Since no streaks are observed in the UV, the
wavelength coverage is extended to longer wavelengths in order to explore
the
severity of streaks in the flats from clouds in the FOV. We have added
exposures
for the HRC in the visible filters to verify the results derived from the
L-flat
campaign and to explore the severity of streaks. We have also added
exposures on
WFC using the minimum exposure time and using filters which will not
saturate
the brightest WFC pixel by more than 10 times the full well.
ACS 9649
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 9482
ACS Pure Parallel Lyman-Alpha Emission Survey {APPLES}
Ly-alpha line emission is an efficient tool for identifying young
galaxies at
high redshift, because it is strong in galaxies with young stars and
little or
no dust — properties expected in galaxies undergoing their first burst
of
star- formation. Slitless spectroscopy with the ACS Wide-Field Camera and
G800L
grism allows an unmatched search efficiency for such objects over the
uninterrupted range 4 <~ z <~ 7. We propose the ACS Pure Parallel
Ly-alpha
Emission Survey {“APPLES”}, to exploit this unique HST capability and
so
obtain the largest and most uniform sample of high redshift Ly-alpha
emitters
yet. Parallel observations will allow this survey to be conducted with
minimal
impact on HST resources, and we will place reduced images and extracted
spectra
in the public domain within three months of observation. We aim to find ~
1000
Ly-alpha emitters, 5 times the biggest current sample of Ly-alpha
emitters.
This
unprecedented sample will provide robust statistics on the populations
and
evolution of Ly-alpha emitters between redshifts 4–7; a robust
measurement of
the reionization redshift completely independent of the Gunn-Peterson
trough;
spatial clustering information for Ly-alpha emitters which would let us
probe
their bias function and hence halo mass as a function of redshift; many
galaxies
at redshift exceeding 6; and lower redshift serendipitous discoveries.
ACS 9674
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 9480
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 9476
Galaxy Evolution in the Richest Clusters at z=0.8: the EDisCS Cluster
Sample
The study of distant cluster galaxies requires two key ingredients: {1}
deep
high-resolution imaging, to constrain galaxy structure; and {2} 8m-class
spectroscopy, to measure stellar content, star-formation rates, dynamics,
and
cluster membership. We will reach both conditions with the addition of
HST/ACS
imaging to our suite of VLT {36 nights} and NTT {20 nights} observations
of 10
confirmed clusters at z~0.8, drawn from the ESO Distant Cluster Survey
{EDisCS}.
The proposed HST/ACS data will complement our existing optical/IR imaging
and
spectroscopy with quantitative measures of cluster galaxy morphologies
{i.e.
sizes and shapes, bulge-disk decompositions, asymmetry parameters}, and
with
measurements of cluster masses via weak lensing. Major advantages unique
to the
EDisCS project include: {i} uniform selection of clusters; {ii} large
enough
sample sizes to characterize the substantial cluster-to-cluster variation
in
galaxy populations; {iii} large quantities of high quality data from 8m
telescopes; {iv} uniform measurements of morphologies, spectroscopic and
photometric redshifts, SEDs, star-formation/AGN activities, and internal
kinematics; {v} optical selection of clusters to complement the X-ray
selection
of almost all high-z clusters in the ACS GTO programs; {vi} forefront
numerical
simulations designed specifically to allow physical interpretation of
observed
differences between the high-z and local clusters.
ACS 9714
Hubble Heritage Observations of the Sombrero Galaxy
The Hubble Heritage Team will observe the entire Sombrero Galaxy {M104,
NGC
4594} with a 6-point ACS mosaic. A color composite image will be released
to the
public via the Heritage website and an STScI photo release.
ACS 9420
Intensive Coverage of the Eta Carinae Event in 2003
For a variety of reasons, HST can provide a very special and unique data
set
when Eta Car experiences its next spectroscopic event in mid-2003.
Explaining
the phenomenon is only part of the motivation. This star and its ejecta
have
unique characteristics that make them important for several branches of
astrophysics; and when a spectroscopic event occurs, it’s like varying
the
parameters in an experiment {or rather, set of experiments}. The 2003
event
will
be the last chance in the forseeable future to obtain such a data set.
Eta
Carinae has extreme parameters; it is mysterious in surprisingly basic
ways; and
HST/STIS can gather useful data on it at a terrific rate. As we explain
below,
the proposed data set will be valuable in several independent ways: It
will
help
solve a specific set of current problems, it will constitute a large and
unique
archival data base for both stellar and nebular astrophysics, and it will
be
well-suited for educational uses.
ACS 9401
The ACS Virgo Cluster Survey
We propose the most comprehensive imaging survey to date of low-redshift,
early-type galaxies. Our goal is to exploit the exceptional imaging
capabilities
of the ACS by acquiring deep images — in the SDSS g^ and z^ bandpasses
— for
163 E, S0, dE, dE, N and dS0 galaxies in Virgo, the nearest rich cluster.
This
extraordinary dataset would likely constitute one of the principal
legacies of
HST, and would have widespread applications for many diverse areas of
astrophysics. Our immediate scientific objectives are threefold: {1}
measure
metallicities, ages and radii for the many thousands of globular clusters
{GCs}
in these galaxies, and use this information to derive the protogalactic
mass
spectrum of each galaxy; {2} measure the central luminosity and color
profile of
each galaxy, and use this information to carry out a completely
independent
test
of the merging hierarchy inferred from the GCs, with the aid of N-body
codes
that simulate the merger of galaxies containing massive black holes; and
{3}
calibrate the z^ -band SBF method, measure Virgo’s 3-D structure, and
carry out
the definitive study of the GC luminosity function’s precision as a
standard
candle. Our proposed Virgo Cluster Survey will yield a database of
unprecedented
depth, precision and uniformity, and will enable us to study the record
of
galaxy and cluster formation in a level of detail which will never be
possible
with more distant systems.
ACS/WFC 9575
Default {Archival} Pure Parallel Program.
The Advanced Camera for Surveys (WFC) was used to test ACS pure parallels
in
POMS.
ACS/WFC/HRC 9445
Gravitational Microlensing in the NGC 3314A-B Galaxy Pair.
The Advanced Camera for Surveys (WFC and HRC) was used to determine the
composition of the dark matter that dominates the masses of galaxies
which
is an
important unsolved problem.
ACS/WFPC2 9488
Cosmic Shear – with ACS Pure Parallel Observations
The ACS, with greater sensitivity and sky coverage, will extend our
ability to
measure the weak gravitational lensing of galaxy images caused by the
large
scale distribution of dark matter. We propose to use the ACS in pure
parallel
{non- proprietary} mode, following the guidelines of the ACS Default Pure
Parallel Program. Using the HST Medium Deep Survey WFPC2 database we have
measured cosmic shear at arc-min angular scales. The MDS image
parameters, in
particular the galaxy orientations and axis ratios, are such that any
residual
corrections due to errors in the PSF or jitter are much smaller than the
measured signal. This situation is in stark contrast with ground-based
observations. We have also developed a statistical analysis procedure to
derive
unbiased estimates of cosmic shear from a large number of fields, each of
which
has a very small number of galaxies. We have therefore set the stage for
measurements with the ACS at fainter apparent magnitudes and smaller, 10
arc-second scales corresponding to larger cosmological distances. We will
adapt
existing MDS WFPC2 maximum likelihood galaxy image analysis algorithms to
work
with the ACS. The analysis would also yield an online database similar to
that
in archive.stsci.edu/mds/
NICMOS 9485
Completing A Near-Infrared Search for Very Low Mass Companions to Stars
within
10 pc of the Sun
Most stars are fainter and less massive than the Sun. Nevertheless, our
knowledge of very low mass {VLM} red dwarfs and their brown dwarf cousins
is
quite limited. Unknown are the true luminosity function {LF},
multiplicity
fraction, mass function, and mass-luminosity relation for red and brown
dwarfs,
though they dominate the Galaxy in both numbers and total mass. The best
way to
constrain these relations is a search for faint companions to nearby
stars.
Such
a search has several advantages over field surveys, including greater
sensitivity to VLM objects and the availability of precise parallaxes
from
which
luminosities and masses can be derived. We propose to complete our
four-filter
NICMOS snapshot search for companions to stars within 10 pc. With a 10
sigma
detection limit of M_J ~ 20 at 10 pc, we can detect companions between 10
and
100 AU that are at least 9 mag fainter than the empirical end of the main
sequence and at least 6.5 mag fainter than the brown dwarf Gl 229B. When
completed, our search will be the largest, most sensitive, volume-limited
search
for VLM companions ever undertaken. Our four-filter search will permit
unambiguous identification of VLM-companion candidates for follow-up
observation. Together with IR speckle and deep imaging surveys, our
program
will
firmly establish the LF for VLM companions at separations of 1-1000 AU
and the
multiplicity fraction of all stars within 10 pc.
NICMOS 9702
NICMOS Parallel Thermal Background
NICMOS Camera 2 pure parallel exposures in the F222M and F237M filters to
establish the stability of the HST+NCS+Instrument thermal emission. This
data
will be compared against the already available Camera 3 measurements in
F222M
which show an increased thermal background.
NICMOS 8791
NICMOS Post-SAA calibration – CR Persistence Part 2
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.
NICMOS 9484
The NICMOS Parallel Observing Program
We propose to manage the default set of pure parallels with NICMOS. Our
experience with both our GO NICMOS parallel program and the public
parallel
NICMOS programs in cycle 7 prepared us to make optimal use of the
parallel
opportunities. The NICMOS G141 grism remains the most powerful survey
tool for
HAlpha emission-line galaxies at cosmologically interesting redshifts. It
is
particularly well suited to addressing two key uncertainties regarding
the
global history of star formation: the peak rate of star formation in the
relatively unexplored but critical 1<= z <= 2 epoch, and the amount of
star
formation missing from UV continuum-based estimates due to high
extinction. Our
proposed deep G141 exposures will increase the sample of known HAlpha
emission-
line objects at z ~ 1.3 by roughly an order of magnitude. We will also
obtain a
mix of F110W and F160W images along random sight-lines to examine the
space
density and morphologies of the reddest galaxies. The nature of the
extremely
red galaxies remains unclear and our program of imaging and grism
spectroscopy
provides unique information regarding both the incidence of obscured star
bursts
and the build up of stellar mass at intermediate redshifts. In addition
to
carrying out the parallel program we will populate a public database with
calibrated spectra and images, and provide limited ground- based optical
and
near-IR data for the deepest parallel fields.
STIS 9608
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 9606
CCD Dark Monitor-Part 2
Monitor the darks for the STIS CCD.
STIS 9688
Connecting the X-Ray and UV Ionized Absorbers in MRK 279
We propose a deep X-ray/UV spectroscopy campaign on the bright Seyfert 1
galaxy
MRK 279, using Chandra LETGS, HST/STIS, and FUSE. Our main scientific
goal
is to
study the AGN outflow seen as an ionized absorber in this galaxy,
focusing on
the crucial connection between the X-ray and UV manifestations of the
outflows.
We will map the ionization and velocity structure, measure the elemental
abundances and then determine the mass and kinetic luminosity flux of the
outflow- all stepping stones for studying the importance of outflows in
the
evolution of AGN and their host galaxies. In addition we will use the
LETGS
data
to determine the existence of relativistic CNO emission lines in the
spectrum.
STIS 9615
Cycle 11 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.
STIS 9708
STIS Pure Parallel Imaging Program: Cycle 11
This is the default archival pure parallel program for STIS during cycle
11.
STIS 8630
The Deepest Far-UV Imaging Survey of Globular Clusters: NGC 6752 and NGC
6397
A few very close binaries can drive the dynamical evolution of an entire
globular cluster. We propose the deepest UV imagery ever obtained on
globular
clusters to search for cataclysmic variables {CVs}. CVs should be
relatively
easy to find in globular cores with HST, but there is a remarkable dearth
of
detected CVs in globular clusters relative to the large numbers predicted
by
tidal capture theory. This calls into serious doubt all of our
understanding of
globular cluster dynamical evolution. If most CVs in globular clusters
are much
fainter than canonical classical and dwarf novae, then tidal capture
theory
{and
our claim to understand cluster evolution} can be salvaged. We propose to
image
the globular clusters NGC 6752 and NGC 6397 in the passband where CVs
emit most
of their radiation: the far UV, and at Lyalpha. Using the FUV-MAMA
detector on
STIS, we will reach an equivalent optical limiting magnitude of M_V = 13
at
S/N=10 which is sensitive enough to detect even the faintest known CVs.
If few
or no faint CVs are found, then theorists will have run out of phase
space and
simple tidal capture theory will be shown to have made an incorrect
prediction.
This would force a major revision in our theory of tidal capture, and our
understanding of globular cluster dynamical evolution.
STIS 9441
Zinc Abundances in Damped Ly-Alpha Systems at z < 0.5: A Missing Link in
the
Chemical History of Galaxies
The evolution of metallicity in damped Lyman alpha {DLA} quasar
absorption
systems is an important constraint on the global star formation history
of the
universe, but remains a big puzzle at present. The H I column density
weighted
mean metallicity in DLAs is expected to rise to solar values at low
redshifts,
based on cosmic chemical evolution models, because the mass-weighted mean
metallicity of local galaxies is near- solar. However, current DLA
abundance
studies are highly uncertain and cannot distinguish between evolution and
no
evolution in the mean metallicity at redshifts 0.4 < z < 3.5. The
existing data
are particularly incomplete because no Zn measurements exist for z < 0.4,
and
only 2 exist for z < 0.5, which spans the past 35-45 % of the age of the
universe. To pin down the cosmic age-metallicity relation all the way to
the
present epoch, we propose to measure Zn abundances in five DLAs at 0.1 <
z <
0.5. We propose to use HST STIS because it is the only existing
instrument that
can measure the necessary UV lines. Our observations will clearly
distinguish
between no metallicity evolution vs. the predicted evolution. Our data
will
also
provide Cr measurements, which will help to estimate the dust abundance.
The
proposed observations are crucial for tying together the absorption and
emission
histories of gas and stars in galaxies and for clarifying the relation of
DLAs
to present-day galaxies.
STIS/CCD/MA1 9982
Intergalactic-Ionized Helium toward HS 1700+6416 at maximum QSO
brightness
We propose to measure the UV energy distribution of HS 1700+6416 {z=2.73}
in the
range 1200-3000 A. Scientific background is that HS 1700 has been
observed
recently by FUSE in a long integration {390 ksec}. Due to an unexpected
brightening of the QSO by a factor of 3 to 4 compared to earlier FUSE and
HUT
observations the new observations yielded a HeII forest spectrum of
spectacular
quality. The aim of the proposed HST observation is to measure the UV
energy
distribution of HS 1700 the knowledge of which is essential for an
optimal
evaluation of the FUSE HeII spectrum.
WF/PC-2 9173
The Pattern of Heavy Element Abundances in a Damped LyAlpha Galaxy.
The WF/PC-2 was used to observe the quasar PKS 1127-143. X-ray absorption
associated with an intervening 21-cm and damped LyAlpha$ absorber at
z=0.312 in
its spectrum has been detected with Chandra. The advantage of the X- ray
measurement is that the derived metallicity is insensitive to ionization,
inclusion of an atom in a molecule, or depletion onto grains. The X-ray
absorption is mostly due to oxygen, and the abundance agrees with the
oxygen
abundance of 16-40 lines in a galaxy at the redshift of the absorber. The
STIS
spectrum will allow measurement of Zn II, an undepleted iron peak
element.
Comparison of the oxygen group measured in the X-rays with the iron peak
nuclei
measured will reveal whether the absorber has a Pop II, halo-type
abundance
pattern or a Pop I, disk-like abundance pattern.
WFPC2 9710
POMS Test Proposal: WFII backup parallel archive proposal
This is a POMS test proposal designed to simulate scientific plans.
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 9594
WFPC2 CYCLE 11 SUPPLEMENTAL DARKS pt2/3
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.) None
COMPLETED OPS REQs: None
OPS NOTES EXECUTED:
1112-1 – Adjust Recharge Ratio Limits for High Sun DOY 2003/136-150 @
136/1816z
SCHEDULED SUCCESSFUL FAILURE TIMES
FGS
GSacq 17 17
FGS REacq 28 28
FHST Update 34 33 2nd of 2
'U1,3FM' updates failed @ 136/2317z; no HSTAR required
LOSS of LOCK
SIGNIFICANT EVENTS: None
