Notice: For the foreseeable future, the daily reports may
contain
apparent discrepancies between some proposal descriptions
and the listed
instrument usage. This is due to the conversion of
previously approved
ACS WFC or HRC observations into WFPC2, or NICMOS
observations
subsequent to the loss of ACS CCD science capability in
late January.
HUBBLE SPACE TELESCOPE - Continuing to collect World Class
Science
DAILY REPORT # 4357
PERIOD COVERED: UT May 07, 2007 (DOY 127)
OBSERVATIONS SCHEDULED
WFPC2 10800
Kuiper Belt Binaries: Probes of Early Solar System
Evolution
Binaries in the Kuiper Belt are a scientific windfall: in
them we have
relatively fragile test particles which can be used as
tracers of the
early dynamical evolution of the outer Solar System. We
propose to
continue a Snapshot program using the ACS/HRC that has a
demonstrated
discovery potential an order of magnitude higher than the
HST
observations that have already discovered the majority of
known
transneptunian binaries. With this continuation we seek to
reach the
original goals of this project: to accumulate a
sufficiently large
sample in each of the distinct populations collected in
the Kuiper Belt
to be able to measure, with statistical significance, how
the fraction
of binaries varies as a function of their particular
dynamical paths
into the Kuiper Belt. Today's Kuiper Belt bears the
imprints of the
final stages of giant-planet building and migration;
binaries may offer
some of the best preserved evidence of that long-ago era.
WFPC2 10832
Solving the microlensing puzzle: An HST high-resolution
imaging approach
We propose to use the HST Advanced Camera for Surveys High
Resolution
Channel to obtain high resolution imaging data for 10
bona-fide LMC
microlensing events seen in the original MACHO survey. The
purpose of
this survey will be to assess whether or not the lens and
source stars
have separated enough to be resolved since the original
microlensing
event took place - about a decade has passed since the
original MACHO
survey and the HST WFPC2 follow-up observations of the
microlensing
events. If the components of the lensing event are
resolved, we will
determine the apparent magnitude and color of both the
lens and the
source stars. These data, in combination with Spitzer/IRAC
data and
Magellan near-IR JHK data, will be used to ascertain the
basic
properties of the lens stars. With the majority of the
microlensing
events in the original MACHO survey observed at the
highest spatial
resolution currently possible, we will be able to draw
important
conclusions as to what fraction of these events have
lenses which belong
to some population of dwarf stars in the disk and what
fraction must be
due to lenses in the halo or beyond. These data will
greatly increase
our understanding of the structure of the Galaxy by
characterizing the
stellar population responsible for the gravitational
microlensing.
WFPC2 10877
A Snapshot Survey of the Sites of Recent, Nearby
Supernovae
During the past few years, robotic {or nearly robotic}
searches for
supernovae {SNe}, most notably our Lick Observatory
Supernova Search
{LOSS}, have found hundreds of SNe, many of them in quite
nearby
galaxies {cz < 4000 km/s}. Most of the objects were discovered
before
maximum brightness, and have follow-up photometry and
spectroscopy; they
include some of the best-studied SNe to date. We propose
to conduct a
snapshot imaging survey of the sites of some of these
nearby objects, to
obtain late-time photometry that {through the shape of the
light and
color curves} will help reveal the origin of their
lingering energy. The
images will also provide high-resolution information on
the local
environments of SNe that are far superior to what we can
procure from
the ground. For example, we will obtain color-color and
color-magnitude
diagrams of stars in these SN sites, to determine the SN
progenitor
masses and constraints on the reddening. Recovery of the
SNe in the new
HST images will also allow us to actually pinpoint their
progenitor
stars in cases where pre- explosion images exist in the
HST archive.
This proposal is an extension of our successful Cycle 13
snapshot survey
with ACS. It is complementary to our Cycle 15 archival
proposal, which
is a continuation of our long-standing program to use
existing HST
images to glean information about SN environments.
WFPC2 11024
WFPC2 CYCLE 15 INTERNAL MONITOR
This calibration proposal is the Cycle 15 routine internal
monitor for
WFPC2, to be run weekly to monitor the health of the
cameras. A variety
of internal exposures are obtained in order to provide a
monitor of the
integrity of the CCD camera electronics in both bays {both
gain 7 and
gain 15 -- to test stability of gains and bias levels}, a
test for
quantum efficiency in the CCDs, and a monitor for possible
buildup of
contaminants on the CCD windows. These also provide raw
data for
generating annual super-bias reference files for the
calibration
pipeline.
NIC1/NIC2/NIC3 8794
NICMOS Post-SAA calibration - CR Persistence Part 5
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.
NIC1/NIC3 10924
Constraints on the Assembly and Dynamical Masses of z~2
Galaxies
We propose deep NICMOS/NIC2 F160W imaging of seven
star-forming galaxies
at z~2. These galaxies comprise an entirely unique sample,
with not only
redshifts measured from optical and near-IR spectra, but
also
SINFONI/VLT near-IR integral field spectroscopic
measurements providing
kinematic maps of H-alpha emission out to radii of >=10
kpc. We aim to
determine the dynamical masses and evolutionary states of
these systems,
as part of the larger goal of understanding how mass is
assembled in
distant galaxies. In order to interpret our novel H-alpha
integral field
maps in terms of mass, we require detailed knowledge of
the structural
parameters of our target objects at rest-frame optical
wavelengths and
on ~1 kpc scales. We want to establish if the mass is
distributed in a
disk, bulge, or merging sub-units, and if we can detect
tidal features
associated with a merger. F160W imaging with NICMOS/NIC2
provides the
perfect combination of sensitivity and resolution to
address these
questions, and arrive at the fundamental quantity: the
dynamical mass.
NIC2 10849
Imaging Scattered Light from Debris Disks Discovered by
the Spitzer
Space Telescope around 21 Sun-like Stars
We propose to use the high-contrast capability of the
NICMOS coronagraph
to image a sample of newly discovered circumstellar disks
associated
with Sun-like stars. These systems were identified by
their strong
thermal infrared {IR} emission with the Spitzer Space
Telescope as part
of the Spitzer Legacy Science program titled "The
Formation and
Evolution of Planetary Systems" {FEPS, P.I.:
M.Meyer}. Modeling of the
thermal excess emission from the spectral energy
distributions alone
cannot distinguish between narrowly confined high-opacity
disks and
broadly distributed, low-opacity disks. By resolving light
scattered by
the circumstellar material, our proposed NICMOS
observations can break
this degeneracy, thus revealing the conditions under which
planet
formation processes are occuring or have occured. For
three of our
IR-excess stars that have known radial-velocity planets,
resolved
imaging of the circumstellar debris disks may further
offer an
unprecedented view of planet-disk interactions in an
extrasolar
planetary system. Even non-detections of the light
scattered by the
circumstellar material will place strong constraints on
the disk
geometries, ruling out disk models with high optical
depth. Unlike
previous disk imaging programs, our program contains a
well-defined
sample of ~1 solar mass stars covering a range of ages
from 3 Myr to 3
Gyr, thus allowing us to study the evolution of disks from
primordial to
debris for the first time. The results from our program
will greatly
improve our understanding of the architecture of debris
disks around
Sun-like stars, and will create a morphological context
for the
existence of our own solar system. This proposal is for a
continuation
of an approved Cycle 14 program {GO/10527, P.I.: D.
Hines}.
WFPC2 11002
A Census of LIRGs in Clusters of Galaxies in the First
Half of the
Universe from the IRAC Shallow Survey
The incidence of LIRGs and ULIRGs is roughly two orders of
magnitude
higher in the field at redshift z > 1, and at these
redshifts such
objects dominate the global star formation activity.
Mergers which fuel
such activity might be expected to enhance the frequency
of LIRGs in
dense environments. We propose to use MIPS to obtain a
census of LIRGs
in z > 1 galaxy clusters from a well defined sample
found in the IRAC
Shallow Survey. Supporting IRAC and HST ACS data are also
requested.
WFPC2 11023
WFPC2 CYCLE 15 Standard Darks - part 1
This dark calibration program obtains dark frames every
week in order to
provide data for the ongoing calibration of the CCD dark
current rate,
and to monitor and characterize the evolution of hot
pixels. Over an
extended period these data will also provide a monitor of
radiation
damage to the CCDs.
WFPC2 11075
The 2006 outburst of RS Oph - Second epoch HST
observations of evolving
structures
We propose to use second epoch HST DD time to perform high
resolution
optical imaging of the 2006 outburst of the Recurrent Nova
RS Ophiuchi,
which underwent its last recorded outburst in 1985. In
this system, high
velocity ejecta from a WD near the Chandrasekhar mass
impact the
companion red giant wind, setting up shock systems
analogous to those in
SNR. Our first epoch observations in July 2006 {day 155}
revealed for
the first time what appear to be the sub-arcsecond optical
counterparts
of the "jets" we have observed in the radio. A
striking similarity to
the double rings of SN 1987A is however evident. In
addition, previously
unseen structures ~1 arcsec to the East and South are
apparent. In
addition to determining the true source geometry and
disentagling the
contributions different regions of the source make to
unresolved
spectra, the specific aims of our second epoch
observations are to
determine {i} the expansion rate of the inner extended
features,
allowing comparison with simple shock models and helping
to constrain
the distance to RS Oph; {ii} whether the eastern "arc"
and southern
"blob" show any motion, helping to determine
whether they are the result
of previous outbursts, and {iii} the rate of change of
emission in the
observed lines, for direct comparison with shock models,
and also to
compare with the overall changes in line fluxes seen in
infrared,
optical and uv spectroscopy. Our work on RS Oph has far
wider-ranging
importance which includes furthering our understanding of
the outbursts
of novae, the structure of red giant winds, jet ejection
and collimation
in astrophysical sources, the progenitors of Type Ia
supernovae and the
evolution of supernova remnants. Continued HST
observations complement
our multi-frequency observing campaign, in particular our
unrivalled
coverage of this event with VLBI.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are
preliminary reports
of potential non-nominal performance that will be
investigated.)
HSTARS: (None)
COMPLETED OPS REQUEST:
18072-1 - PCS KF OOT Support
18069-3 - MSS/CSS/Gyro2 KF Initialization Convergence
Testing for SMS 127
COMPLETED OPS NOTES: (None)
SCHEDULED
SUCCESSFUL
FGS GSacq
07
07
FGS REacq
07
07
OBAD with Maneuver
27
27
SIGNIFICANT EVENTS:
Evaluation of Universal Kalman Filter performance
continued. Details
follow.
The KF was halted at 127/18:15 (OR 18069-3). The filter
was restarted at
127/18:18 with the CSS disabled, the Gyro2 input enabled,
during orbit
day, during a vehicle slew and during an M2G guiding
interval and during
a slow changing B-field. All UKF parameters showed nominal
operation.
The test was an MSS/Gyro2 Initialization test case during
a vehicle slew
with a slow changing B-field (M_G2_IVS, Test #35).
The KF was reconfigured and restarted at 127/19:14 with
the CSS and both
gyro inputs disabled to leave the filter in an MSS only
configuration.
This configuration is to help provide a earlier baseline
set of data for
PCS analysis and it will remain the default configuration
outside of
other KF convergence testing for the remainder of the week.