HST Daily Report # 3319
DAILY REPORT # 3319
PERIOD COVERED: DOY 72
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.
STIS 9130
The iron abundance in the Magellanic Clouds and Bridge
The spectra of early-type main-sequence stars provide excellent probes of
the
current chemical composition of galaxies. The physics of their
atmospheres are
well understood, while their surfaces will normally be unaffected by the
products of interior nuclear reactions. We have previously used optical
spectra
of such targets to map the abundances of light metals {such as C, N, O,
Mg, Si}
in our Galaxy, in the Magellanic Clouds and in a Bridge of material
connecting
the latter. However, we have been unable to obtain iron group abundances
for the
Magellanic System due to the intrinsic weakness of the optical Fe II/III
spectra
and the system’s low metallicity. Here we propose observations of strong
Fe III
ultraviolet lines for two Bridge stars, plus an LMC target. These will be
supplemented by AAT and ESO optical spectroscopy plus HST spectra for two
previously observed targets in the middle of the Bridge and in the SMC.
Using
non-LTE model atmosphere and careful differential methods, relative
abundances
accurate to 0.1 dex should be achievable. These five stars will allow us
to
determine key element abundances and ratios {eg. O/Fe} in both Clouds and
across
the Bridge. As well as providing the first detailed comparison of the
Bridge’s
metallicity with those of its parent Clouds, it will clarify the
evolutionary
history of this system.
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.
ACS 9427
Globular Cluster Systems in Supergiant E Galaxies
he most populous globular cluster systems are found in the giant
ellipticals at
the centers of galaxy clusters {Brightest Cluster Galaxies}. It is among
this
BCG class that the characteristics of globular cluster systems display
their
widest range in metallicity distribution and specific frequency and thus
confront galaxy formation models with their most varied challenges. Were
these
systems built primarily by early in situ conversion of gas clouds, by
later
mergers, or by ongoing accretions of dwarfs? Their extensive halo cluster
systems contain many clues to these relic events. BCGs are the biggest
and
rarest type of galaxy, and to date the globular clusters in only two BCGs
{M87,
NGC 1399} are well studied. The ACS camera now brings many more such
systems
within reach. We propose to image the globular cluster systems in 13 BCGs
in the
distance regime cz ~eq 2000 – 5000 km s^-1. With deep {B, I} exposures we
will
measure the globular cluster metallicity distribution functions, specific
frequency, radial distributions, and luminosity distributions, as well as
correlations among these quantities. This work will be the first
comprehensive,
homogeneous deep survey of globular clusters in BCGs. The superior area
and
sensitivity of ACS will yield a gain of a factor of eight over previous
WFPC2
studies for sample size and metallicity discrimination.
ACS 9440
The Composition of Io’s Pele Plume
We propose to determine the composition of Io’s largest volcanic plume,
Pele,
with unprecedented accuracy. This will give us new constraints on the
temperatures, pressures, and magma composition of this volcano, and thus
an
improved window into Io’s interior. We will use the proven Jupiter
transit
spectroscopy technique, which resulted in the discovery of S_2 gas in the
Pele
plume, but will use exposures that are 4 times longer than in the
discovery
observations. This will allow us to accurately measure plume SO_2
abundances,
seen only with low S/N in the discovery observations, and possibly SO, in
addition to S_2, and gives the chance to discover other, currently
unknown,
plume components. We will also use ACS to obtain UV and visible images of
the
Pele plume in reflected light prior to Jupiter transit, to constrain the
dust
abundance and particle size in the plume. This will allow refined
estimates of
plume dust/gas ratios and resurfacing rates. We will repeat the
observations
four times to build up S/N to even higher levels, and to look for time
variability in both dust and gas abundance and chemistry.
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
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.
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.
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 9589
WFPC2 Decontaminations and Associated Observations Pt. 1/3
This proposal is for the monthly WFPC2 decons. Also included are
instrument
monitors tied to decons: photometric stability check, focus monitor, pre-
and
post-decon internals {bias, intflats, kspots, & darks}, UV throughput
check,
VISFLAT sweep, and internal UV flat check.
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.
FGS 9603
Monitoring FGS1r’s Interferometric Response as a Function of Spectral
Color
This proposal obtains reference point source Transfer Functions
{S-Curves} for
FGS1r through the F583W filter and the F5ND attenuator at the center
position of
the FGS1r FOV for a variety of stars with different stellar spectral
colors. The
data will be added to the library of point source interferograms that was
assembled from the Cycles 8 and 9 calibration programs. These Transfer
Functions
are needed to support the analysis of GO science data for the study of
close and
wide binary star systems and for determining the angular size and shape
of
extended sources. This proposal observes stars that have been observed in
previous cycles to check for long term temporal stability of the FGS1r
S-curves.
This proposal monitors the cycle 10 calibration the FGS1r Lateral Color
response
{using stars Latcol-A and Latcol-B}, as well as calibrates the
"Pos/Trans" bias
of a star’s position as determined from Transfer mode and Position mode
observations, and finally the shift of a star’s centroid when observed
with
F5ND
relative to that when observed with F583W {the cross filter shift} is
calibrated
for the fainter stars in this proposal {stars brighter than V=8 can not
be
observed with F583W.}
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.
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.
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.)
HSTAR 8958: GSacq(3,1,3) results to Finelock Backup (1,0,1). The
GSACQ(3,1,3)
scheduled at 072/16:29:36 – 16:36:52 resulted to
finelock backup(1,0,1)
using FGS#1 due to scan step limit exceeded on
FGS#3.
Possible
observations affected: WFPC 218,219 ACS 144. The
guide star acquisition
for this observation was non-nominal, further
analysis will determine if
a repeat observation is required. Under
investigation.
COMPLETED OPS REQs:
None
OPS NOTES EXECUTED:
1085-0 SSR ENGINEERING DUMP @ 072/1908z
SCHEDULED SUCCESSFUL FAILURE TIMES
FGS GSacq 08 08
FGS REacq 07 07
FHST Update 14 14
LOSS of LOCK
SIGNIFICANT EVENTS:
Aft Flight Deck Command Dry Run (March 12, 2003) Objectives: To dry run
AFD
commands for
SM4 to ensure that the CCS verifiers responded with correct values. This
first test is
also verifying the SM4 AFD test procedures and the SOCs scenario files.
The
test was a
partial success. Testing was delayed by the inability to access the DM14
calibration
report from CCSPDT or the legacy DM14 bluebooks from the web. Everett
Pope
responded
quickly to reload the PDT application on select SMOR machines before
testing resumed.
Several mnemonic conflicts were resolved by the SOC filtering said
mnemonics out of
there database during testing. All considered this was a good first dry
run
with actions
resulting for both teams. SOC and HITT will meet on Friday to discuss
all
issues.
