NASA Hubble Space Telescope Daily Report # 3551
HUBBLE SPACE TELESCOPE – Continuing to collect World Class Science
DAILY REPORT # 3551
PERIOD COVERED: DOY 43
OBSERVATIONS SCHEDULED
ACS 10058
Improved wavelength calibration for the WFC G800L grism
ACS G800L observations of an emission line star {the WC Wolf-Rayet star
WR96}
and a compact planetary nebula {LMC-SMP81} will be obtained to provide
improved
coverage of the field variation of the dispersion solution for the WFC and
G800L
grism. A direct image and a corresponding grism image will be taken at many
different positions across the WFC field. By fitting the emission lines, the
field dependence of the wavelength zero point and dispersion will be
measured.
The WR star was already used in Cycle 11 calibrations and these observations
provide improved spatial coverage to map the variation of the dispersion
with
position. The observations of the fainter planetary nebula provide an
independent wavelength calibration for a few points over the field.
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/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. HST is the only facility that can be used to
search
for binaries among such faint objects {V>17.5}. 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/WFC 10059
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 9744
HST Imaging of Gravitational Lenses
Gravitational lenses offer unique opportunities to study cosmology, dark
matter,
galactic structure, galaxy evolution and quasar host galaxies. They are
also the
only sample of galaxies selected based on their mass rather than their
luminosity or surface brightness. While gravitational lenses can be
discovered
with ground-based optical and radio observations, converting them into
astrophysical tools requires HST. HST has demonstrated that it is the only
telescope that can in each case precisely locate the lens galaxy, measure
its
luminosity, color and structure, and search for lensed images of the source
host
galaxy given the typical image separations of ~1”. We will obtain ACS/WFC
V and
I images and NICMOS H images of 21 new lenses never observed by HST and
NICMOS H
images of 16 lenses never observed by HST in the IR. As in previous cycles,
we
request that the data be made public immediately.
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/
FGS 9879
An Astrometric Calibration of the Cepheid Period-Luminosity Relation
We propose to measure the parallaxes of 10 Galactic Cepheid variables. There
is
no other instrument on or off the earth that can consistently deliver HST
FGS
level of precision for critical parallaxes. 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.
FGS 9971
FGS Astrometry of a Star Hosting an Extrasolar Planet: The Mass of Upsilon
Andromedae d
We propose observations with HST/FGS to determine the astrometric elements
{perturbation orbit semimajor axis and inclination} produced by the
outermost
extra-solar planet orbiting the F8V star Upsilon Andromedae. These
observations
will permit us to determine the actual mass of the planet by providing the
presently unknown sin i factor intrinsic to the radial velocity method which
discovered this object. An inclination, i = 30degrees, within the range of
one
very low precision determination using reanalyzed HIPPARCOS intermediate
data
products, would produce the observed radial velocity amplitude, K = 66 ms
with a
companion mass of ~8 M_Jupiter. Such a mass would induce in Upsilon
Andromedae a
perturbation semi-major axis, Alpha = 0arcs0012, easily within the reach of
HST/FGS fringe tracking astrometry. The proposed observations will yield a
planetary mass, rather than, as previous investigations have done, only
suggest
a planetary mass companion.
HST 9382
A Large Targeted Survey for z < 1.6 Damped Lyman Alpha Lines in SDSS QSO
MgII-FeII Systems.
We have searched the first public release of SDSS QSO spectra for low-z
{z<1.65}
metal absorption lines and found over 200 large rest equivalent width
MgII-FeII
systems. Previously, we empirically showed that such systems are good
tracers of
large neutral gas columns, with ~50% being classical damped Lyman alpha
{DLA}
systems {N_HI>=2*10^20 cm^-2}. Here we propose to follow up a well-defined
subset of 79 of them to search for DLAs with 0.47<z<1.60. Only QSOs brighter
than g’=19 were selected. The QSO emission and DLA absorption redshifts were
constrained to virtually eliminate data loss due to intervening Lyman limit
absorption. Consequently, we expect to discover ~40 new DLAs, which is a
three-fold increase in this redshift interval. This will significantly
improve
our earlier low-z DLA statistical results on their incidence, cosmological
mass
density, and N_HI distribution. The results will also allow us to better
quantify the empirical DLA — metal-line correlation. With this improved
understanding, the need for follow-up UV spectroscopy will lessen and, with
the
release of the final database of SDSS QSO spectra {an ~25-fold increase},
the
number of low-z DLAs could be increased arbitrarily. Thus, the power of the
large and statistically-sound SDSS database in combination with a proven
technique for finding low-z DLAs will, over the next few years, essentially
solve the problem of making an accurate determination of the cosmic
evolution of
the neutral gas component down to z~0.4.
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.
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.
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 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 10085
STIS Pure Parallel Imaging Program: Cycle 12
This is the default archival pure parallel program for STIS during cycle 12.
STIS/CCD/MA1 9511
Connecting the UV and X-ray Warm Absorbers in NGC 5548
In the last Chandra cycle, we were awarded a joint Chandra/HST proposal to
study
the warm absorber in NGC 5548 and to obtain a definitive answer about the
connection between the warm absorber and the UV absorber in this object. We
are
confident that the deep Chandra observation {500 ksec} will allow for an
unprecedented determination of the kinematic components in the warm absorber
as
well as accurate column density measurements from several line series.
However,
two new lines of investigation that appeared after the submission of the
Chandra/HST proposal, suggest that the original modest request for HST time
will
not suffice to obtain reliable column density measurements for the UV
absorber.
In view of the new evidence, we need a a higher S/N in the proposed
observations
to allow for accurate UV column densities determination. Absorption features
in
both the UV and warm absorbers are known to be variable. Therefore, it will
be
highly unfortunate if the large investment of Chandra time will not be
accompanied by enough simultaneous HST time to ensure an accurate
measurements
of the UV absorber. Without these it will be very difficult to draw
conclusions
concerning the relationship between the two absorbers. We therefore ask for
20
additional STIS E140M Echelle orbits.
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.
WFPC2 10082
POMS Test Proposal: WFII backup parallel archive proposal
This is a POMS test proposal designed to simulate scientific plans
WFPC2 10084
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.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are preliminary reports of
potential non-nominal performance that will be investigated.)
HSTAR 9321: While reviewing trending data, PCS SE noted a Loss of Lock
(LOL)
had occurred after successful GS Re-acquisition
(1,2,1) and science
had been initiated @ 034/10:35:15Z. A LOL was
detected (by change in #44 CMD)
prior to TERMEXP @ 034/11:19:50Z. LOL recovery
started @ 034/11:19:52
and was completed successfully, with science
initiated again @ 034/11:21:53Z.
Under investigation.
COMPLETED OPS REQs: None
OPS NOTES EXECUTED: None
SCHEDULED SUCCESSFUL FAILURE TIMES
FGS GSacq 10 10
FGS REacq 07 07
FHST Update 20 20
LOSS of LOCK
SIGNIFICANT EVENTS:
PSS Serial Testing scheduled 044/12:00Z – 21:00Z with GDOC, SOC,
and HITT using CCS "C" String with CCS Release 4.0.3.1 and
PRD S07300. The purpose of this testing is to verify CCSPSS
Release 3.3 can simulate HST for telemetry transmission and
command response via serial link from Building 25.
