HST Daily Report # 3316
DAILY REPORT # 3316
PERIOD COVERED: DOY 69
OBSERVATIONS SCHEDULED
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.
ACS 9352
The Deceleration Test from Treasury Type Ia Supernovae at Redshifts 1.2 to
1.6
Type Ia supernovae {SNe Ia} provide the only direct evidence for an
accelerating
universe, an extraordinary result that needs a rigorous test. The case for
cosmic acceleration rests on the observation that SNe Ia at z ~ 0.5 are ~
0.25
mag fainter than they would be in a universe without acceleration. A
powerful
and straightforward way to assess the reliability of the SN Ia measurement
and
the conceptual framework of its interpretation is to look for cosmic
deceleration at z >= 1. This would be a clear signature of a mixed
dark-matter
and dark-energy universe. Systematic errors in the SN Ia result attributed
to
grey dust or cosmic evolution of the SN Ia peak luminosity would not show
this
change of sign. We have demonstrated proof of this concept with a single SN
Ia,
SN 1997ff at z = 1.7, found and followed by HST. The results suggest an
early
epoch of deceleration, but this is too important a conclusion to rest on
just
one object. Here we propose to use HST for observations of six SNe Ia in the
range 1.2 <= z <= 1.6, that will be discovered as a byproduct from proposed
Treasury programs for high-latitude ACS surveys. Six objects will provide a
much
firmer foundation for a conclusion that touches on important questions of
fundamental physics.
STIS/CCD/MA1 9357
Towards a global understanding of accretion physics –, Clues from an UV
spectroscopic survey of cataclysmic variables
Accretion inflows and outflows are fundamental phenomena in a wide variety
of
astrophysical environments, such as Young Stellar Objects, galactic
binaries,
and AGN. Observationally, cataclysmic variables {CVs} are particularly well
suited for the study of accretion processes. We propose to carry out a STIS
UV
spectroscopic snapshot survey of CVs that fully exploits the diagnostic
potential of these objects for our understanding of accretion physics. This
survey will provide an homogenous database of accretion disc and wind
outflow
spectra covering a wide range of mass transfer rates and binary
inclinations. We
will analyse these spectra with state-of-the-art accretion disc model
spectra
{SYNDISK}, testing our current knowledge of the accretion disc structure,
and,
thereby, providing new insight into the so far not well understood process
of
viscous dissipation. We will use our parameterised wind model PYTHON for the
analysis of the radiation driven accretion disc wind spectra, assessing the
fundamental question whether the mass loss rate correlates with the disc
luminosity. In addition, our survey data will identify a number of systems
in
which the white dwarf significantly contributes to the UV flux, permitting
an
analysis of the impact of mass accretion on the evolution of these compact
stars. This survey will at least double, if not triple, the number of
high-quality accretion disc / wind outflow / accreting white dwarf spectra,
and
we waive our proprietary rights to permit a timely use of this database.
STIS 9421
UV Observations of Hubble Flow Type Ia Supernovae
Two independent research groups have presented compelling evidence for an
accelerating universe from the observation of high-redshift Type Ia
supernovae
{SNe Ia}. These findings have such important ramifications for cosmology
that
every effort must be made to thoroughly test the calibrated standard candles
on
which they are based, improve upon our understanding of the underlying
physics
of the SN Ia explosion mechanism and attempt to constrain or determine their
progenitors. Here we propose to obtain STIS UV spectra of five Hubble Flow
SNe
Ia. The spectra will be taken at weekly intervals over a range in time
starting
slightly before maximum light and extending to +30 days. These observations
will
accomplish the following three goals: {1} Calibration of the rest frame UV
light
curves of SNe Ia and an assessment of their potential use as distance
indicators
through UV light curve shape analyses. {2} Improvement in our understanding
of
the physics of SNe Ia, metallicity/evolutionary effects and correlations
between
peak brightness and UV spectral features. {3} Calibration of the SNe Ia
previously observed by HST at high-redshift. For z > 0.8 SNe Ia discovered
by
the Supernova Cosmology Project, the High-Z Supernovae Search Team and
future
HST discovered SNe Ia {like SN 1997ff found in the HDF} this data is
crucial for
proper cross-filter K-corrections and calibration of the supernova
photometry.
ACS/STIS 9451
ACS Imaging and STIS Spectroscopy of Binary Brown Dwarfs
We have compiled a sample of 9 spatially resolved binary brown dwarfs {18
objects}, and now propose ACS imaging and STIS spectroscopic follow-up
observations. While theoretical models on the interplay of chemical and
physical
processes governing brown dwarf atmospheres have reached a high level of
sophistication, interpretation of observational data remains difficult. As
brown
dwarfs never stabilize themselves on the hydrogen main sequence, there is
always
an ambiguity between the temperature or luminosity of any brown dwarf and
its
mass or age. The individual components of brown dwarf binaries, however, are
expected to be coeval and have the same underlying chemical composition.
This
provides crucial constraints on any model, thus greatly reducing the number
of
the free parameters. The aim is to obtain photometric and spectroscopic data
to
probe the physical and chemical properties of the brown dwarf atmospheres,
as
well as second epoch astrometric data to characterize th e orbital motion.
The
study will provide important feedback on theoretical model atmospheres and
evolutionary tracks for brown dwarfs. As such, it will be an important step
towards a better understanding of objects with spectral properties
intermediate
between those of giant planets and late-type stars.
ACS 9463
Are OH/IR stars the youngest post-AGB stars? An ACS SNAPshot imaging survey
Essentially all well-characterized preplanetary nebulae {PPNs}– objects in
transition between the AGB and planetary nebula evolutionary phases – are
bipolar, whereas the mass-loss envelopes of AGB stars are strikingly
spherical.
In order to understand the processes leading to bipolar mass-ejection, we
need
to know at what stage of stellar evolution does bipolarity in the mass-loss
first manifest itself? We have recently hypothesized that most OH/IR stars
{evolved mass- losing stars with OH maser emission} are very young PPNe. We
propose an ACS/SNAPshot imaging survey of a large, morphologically unbiased
sample of these objects, selected using their IRAS 12-to-25micron colors.
Our
ground-based imaging study of OH/IR stars has revealed a few compact bipolar
objects, supporting our hypothesis. However since most objects remain
unresolved, HST observations are needed to determine how and when the
bipolar
geometry asserts itself. Our complementary program of interferometric
mapping of
the OH maser emission in our sources is yielding kinematic information with
spatial resolution comparable to that in the HST images. The HST/radio data
will
provide crucial input for theories of post-AGB stellar evolution. In
addition,
these data will also indicate whether the multiple concentric rings,
“searchlight beams”, and truncated equatorial disks recently discovered
with
HST in a few PPNs, are common or rare phenomena.
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/WFPC2 9481
Pure Parallel Near-UV Observations with WFPC2 within High-Latitude ACS
Survey
Fields
In anticipation of the allocation of ACS high-latitude imaging survey{s}, we
request a modification of the default pure parallel program for those WFPC2
parallels that fall within the ACS survey field. Rather than duplicate the
red
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. We will determine 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.
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.
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
CAL/WF2 9597
Intflat Sweep, Visflat Sweep, and Filter Anomaly Check
No abstract available.
WFPC2 9598
Earth Flats
This proposal monitors flatfield stability. This proposal obtains sequences
of
Earth streak flats to construct high quality flat fields for the WFPC2
filter
set. These flat fields will allow mapping of the OTA illumination pattern
and
will be used in conjunction with previous internal and external flats to
generate new pipeline superflats. These Earth flats will complement the
Earth
flat data obtained during cycles 4-10.
WFPC2 9599
WFPC2 Cycle 11 UV Earth Flats
Monitor flat field stability. This proposal obtains sequences of earth
streak
flats to improve the quality of pipeline flat fields for the WFPC2 UV filter
set. These Earth flats will complement the UV earth flat data obtained
during
cycles 8-10.
STIS 9605
CCD Dark Monitor-Part 1
Monitor the darks for the STIS CCD
STIS 9607
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 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.
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 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 9673
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
WFPC2 9676
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 9699
POMS Test Proposal: WFII backup parallel archive proposal
This is a POMS test proposal designed to simulate scientific plans.
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.
STIS 9706
STIS Pure Parallel Imaging Program: Cycle 10
This is the default archival pure parallel program for STIS during cycle 10.
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: NONE
SCHEDULED SUCCESSFUL FAILURE TIMES
FGS GSacq 08 08
FGS REacq 07 07
FHST Update 20 20
LOSS of LOCK
SIGNIFICANT EVENTS:
DSS-16 Interface Test scheduled for 3/10/03. Test cancelled by HUBBLE NOPE,
DSN16 had preventive maintenance scheduled along with HST test. Site 16
could not support both activities. Test will be re-scheduled in the near
future.
