HST Daily Report # 3358
HUBBLE SPACE TELESCOPE
DAILY REPORT # 3358
PERIOD COVERED: DOY 127
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/WFC 9351
Determining Hubble’s Constant from Observations of Cepheids in the Host
Galaxy
of SN Ia 1994ae
We propose to determine the luminosity of the type Ia supernova {SN Ia}
1994ae
by observing Cepheids in the host spiral galaxy NGC 3370. Modern CCD
photometry
has yielded an extremely tight Hubble diagram for SNe Ia with a precisely
determined intercept {i.e., Delta H_0/H_0} 1 measurement of the true
Hubble
constant is still limited by the calibration. The HST calibration of all
but a
few SNe Ia observed to date is significantly compromised by the
systematics of
photographic photometry and host galaxy extinction, as well as by the
photometric uncertainties associated with WFPC2. In contrast, SN 1994ae
is one
of the very best-observed SNe Ia with CCD photometry. The exquisite B, V,
R, and
I light curves are well-sampled beginning 10 days before maximum
brightness, and
they indicate little reddening. From our supernova photometry and the
current
provisional SN Ia calibration we would find a distance of 30 +/- 2.1 Mpc,
well
within the range where ACS can accurately observe Cepheid light curves
and
distinguish Cepheids from nonvariable stars.
NICMOS 9386
Infrared Photometry of a Statistically Significant Sample of KBOs
While the discovery rate of Kuiper Belt objects is accelerating, the
physical
study of this new region of the solar system has been slowed by a lack of
basic
astrophysical data. Photometric observations of the majority of the more
than
400 known KBOs and Centaurs are rudimentary and incomplete, particularly
in the
infrared. The multicolor optical-infrared photometry that exists for a
small
subset of KBOs often shows significant discrepancies between observations
by
different observers. Their intrinsic faintness puts them at the practical
limits
of ground-based systems. In July 2001 we began what will be the largest
uniform
sample of optical photometry of KBOs with a WFPC2 SNAPSHOT program that
will
perform accurate photometry at V, R, and I on a sample of up to 150
targets. We
seek to greatly enhance the value of this survey by obtaining J and H
photometry
on the same sample using NICMOS. Combined optical and infrared broad band
photometry is a far more powerful tool for physical studies than is
either
alone. Our sample includes objects that will be observed at thermal
infrared
wavelengths by SIRTF and will be used with those data to derive the first
accurate diameters, albedos, and surface properties for a large sample of
KBOs.
GO 9428
SINS: The Supernova Intensive Study– Cycle 11
Supernovae create the chemical history of the Universe, energize the
interstellar gas, form the spine of the extragalactic distance scale, and
provide the only direct evidence for an accelerating universe. SINS is a
program
to study supernovae, near and far. HST is the perfect match in field and
scale
for spatially-resolved observations of SN 1987A. There, a violent
encounter
between the fast-moving debris and the stationary inner ring is well
underway.
Monitoring this interaction will help solve the riddles of stellar
evolution
posed by the enigmatic three-ring system of SN 1987A. Our UV observations
of
Ly-Alpha emission reveal a remarkable reverse shock that provides a
unique
laboratory for studying fast shocks and a powerful tool for dissecting
the
structure of the vanished star. For more distant events, we propose
Target-of-Opportunity observations. In addition to one bright new
supernova in
Cycle 11 discovered by any search at any time, we propose to discover two
supernovae for study in the ultraviolet at times specified in advance,
using the
Lick Observatory Supernova Search. SINS will study the historic SN 1987A,
explore UV emission from supernovae, and press late-time observations of
supernovae into uncharted territory of infrared catastrophes, light
echoes, and
stellar remnants.
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.
ACS 9462
Systemic and Internal Proper Motions of the Magellanic Clouds from
Astrometry
with ACS
We request first epoch observations with ACS of Magellanic Cloud fields
centered
on background quasars. Second epoch observations will be requested ~ 5
years
later to allow the measurement of the systemic and internal proper
motions of
the Clouds with error <~0.05 mas/year. These motions are of fundamental
importance. The systemic motions of the LMC and SMC probe the
gravitational
potential of the dark halo. The internal proper motion due to rotation
can be
exploited to yield a rotational parallax distance to the LMC; the first
time
that this will be done for any galaxy. This is particularly important for
the
LMC because of its crucial role in the extragalctic distance ladder.
Previous
measurements of the proper motion of the LMC yield a systemic component
ranging
from 1.4 mas/year to 3.4 mas/year {differing by several times the quoted
errors}, with no useful determination of the internal motions. The main
problem
with measurements of the proper motion of the LMC has been the lack of a
sample
of background quasars to use as reference frame. We have recently been
able to
identify a sample of 54 quasars behind the Magellanic Clouds from their
variability characteristics in the MACHO database. With this sample and
the
advent of ACS an accurate proper motion measurement has become possible
for the
very first time.
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 9468
ACS Grism Parallel Survey of Emission- line Galaxies at Redshift z pl 7
sight over the redshift interval 0 < z pl 7. We request ACS parallel
observations of duration more than one orbit at high galactic latitude to
identify ~ 300 HAlpha emission-line galaxies at 0.2 pl z pl 0.5, ~ 720 O
IILambda3727 emission-line galaxies at 0.3 pl z pl 1.68, and pg 1000
Ly-alpha
emission-line galaxies at 3 pl z pl 7 with total emission line flux f pg
2*
10^-17 ergs s^-1 cm^-2 over 578 arcmin^2. We will obtain direct images
with the
F814W and F606W filters and dispersed images with the WFC/G800L grism at
each
position. The direct images will serve to provide a zeroth order model
both for
wavelength calibration of the extracted 1D spectra and for determining
extraction apertures of the corresponding dispersed images. The primary
scientific objectives are as follows: {1} We will establish a uniform
sample of
HAlpha and O II emission-line galaxies at z<1.7 in order to obtain
accurate
measurements of co-moving star formation rate density versus redshift
over this
redshift range. {2} We will study the spatial and statistical
distribution of
star formation rate intensity in individual galaxies using the spatially
resolved emission-line morphology in the grism images. And {3} we will
study
high-redshift universe using Ly-alpha emitting galaxies identified at z
pl
7 in
the survey. The data will be available to the community immediately as
they are
obtained.
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
characterizing the evolution of hot pixels
WFPC2 9598
Earth Flats
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.
STIS 9606
CCD Dark Monitor-Part 2
Monitor the darks for the STIS CCD.
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 9613
STIS CCD Spectroscopic Flats C11
Obtain CCD flats on the STIS CCD in spectroscopic mode.
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 9633
STIS parallel archive proposal – Nearby Galaxies – Imaging and
Spectroscopy
Using parallel opportunities with STIS which were not allocated by the
TAC, we
propose to obtain deep STIS imagery with both the Clear {50CCD} and
Long-Pass
{F28X50LP} filters in order to make color-magnitude diagrams and
luminosity
functions for nearby galaxies. For local group galaxies, we also include
G750L
slitless spectroscopy to search for e.g., Carbon stars, late M giants and
S-type
stars. This survey will be useful to study the star formation histories,
chemical evolution, and distances to these galaxies. These data will be
placed
immediately into the Hubble Data Archive.
ACS 9657
ACS Internal Flat Field Stability
The flat field stability and characterization obtained during the ground
calibration and SMOV phases will be tested and verified through a
sub-sample of
the filter set. Only internal exposures with the calibration lamps will
be
required.
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.
NICMOS 9702
NICMOS Parallel Thermal Background
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 9708
STIS Pure Parallel Imaging Program: Cycle 11
This is the default archival pure parallel program for STIS during cycle
11.
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 9710
POMS Test Proposal: WFII backup parallel archive proposal
This is a POMS test proposal designed to simulate scientific plans.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are preliminary reports
of
potential non-nominal performance that will be investigated.)
COMPLETED OPS REQs:
16973-3 Add Battery #2 Discharge off Commands to SMAC01 @ 128/02:02:57z
OPS NOTES EXECUTED:
- 0915-1 HSTAR Documentation for FHST Map/Update Failures @ 127/2242z
- 1106-0 Battery 5 Pressure Limit Adjustment @ 127/1526z
- 1107-0 Limit Adjustment for CCC K51 to Level 2 Change (Batt 2 Test) @128/0443z
SCHEDULED SUCCESSFUL FAILURE TIMES
FGS
GSacq 08 08
FGS REacq 07 07
FHST
Update 13 12
127/22:42:12z
LOSS of LOCK
SIGNIFICANT EVENTS:
ESB code 901 is "FHST Error Box Fail" due to the FHST update failure
(no HSTAR required per ON # 0915-1)
Battery 2 Capacity Test was initiated at the first scheduled
opportunity. See
OR 16970-2 with attached Battery Reconditioning Procedure: Battery 2.
Initial
set-up commanding started @ 127/12:09Z with configuration of
TMDIAGs. Battery 2
was connected to the Diode Bus C @ 127/13:01Z and high rate discharge was
initiated @ 127/13:06Z and continued nominally until 128/01:52Z when the
15
Volt
termination point was reached. Throughout the discharge, the 5 battery
system
maintained voltage, rate of charge and state of charge margins. Battery
2 was
place back on charge @ 128/02:22Z and is recovering well. To aid the
recovery,
Battery 5 is being operated at the VTFE level. Due to Battery 5
characteristics
and this elevated Voltage cut-off, some battery warming is
expected. Anticipated
reconfiguring FSW back to a 6-battery system on Day 129. Preliminary
estimate of
Battery 2 capacity is 59 Ah. Estimated does not include merged data
recorded
during ZOEs and is missing data where Battery 2 shared the spacecraft
load.
Final results are expected to improve. Battery 2 was last tested in
November
1998 with a yield of 70.4 Ah.
