Daily Report #4583
Cooper, Joe
DAILY REPORT # 4583
PERIOD COVERED: UT April 04,05,06, 2008 (DOY 095,096,097)
OBSERVATIONS SCHEDULED
NIC1/NIC2/NIC3 8795
NICMOS Post-SAA calibration - CR Persistence Part 6
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.
WFPC2 11509
Astrometric Centroiding for Saturated Stars
This is a WFPC2 program that will calibrate the use of diffraction
spikes to centroid saturated stellar images. The purpose is to provide
an astrometric calibration of this method, which has been used for a
series of HST observations of Sirius and its companion, Sirius being
so bright that it is saturated in the shortest possible WFPC2
exposures. We will obtain both unsaturated and saturated images of 109
Vir, a star of type A0 V whose color is very similar to that of
Sirius, but it is more than 5 mag fainter. This will allow a direct
calibration of any offsets between the centroid indicated by the
diffraction spikes (or other PSF features) and the true stellar
centroid.
WFPC2 11343
Identifying the host galaxies for optically dark gamma-ray bursts
We propose to use the high spatial resolution capabilities of Chandra
to obtain precise positions for a sample of Gamma-ray bursts (GRBs)
with no optical afterglows, where the optical light is suppressed
relative to the X-ray flux. These bursts are likely to be highly
obscured and may have different environments from the optically bright
GRBs. Our Chandra observations will (unlike Swift-XRT positions) allow
for the unique identification of a host galaxy. To locate these host
galaxies we will follow up our Chandra positions with deep optical and
IR observations with HST. The ultimate aim is to understand any
differences between the host galaxies of optically dark and bright
GRBs, and how these affect the use of GRBs as tracers of starformation
and galaxy evolution at high redshift.
NIC1/NIC2/NIC3 11330
NICMOS Cycle 16 Extended Dark
This takes a series of Darks in parallel to other instruments.
S/C 11320
NICMOS Focus Monitoring Cycle 16
This program is a version of the standard focus sweep used since cycle
7. It has been modified to go deeper and uses more narrow filters for
improved focus determination. A new source was added in Cycle 14 in
order to accommodate 2-gyro mode: the open cluster NGC1850. This
source is part of the current proposal. The old target, the open
cluster NGC3603, will be used whenever available and the new target
used to fill the periods when NGC3603 is not visible. Steps: a) Use
refined target field positions as determined from cycle 7 calibrations
b) Use MULTIACCUM sequences of sufficient dynamic range to account for
defocus c) Do a 17-point focus sweep, +/- 8mm about the PAM mechanical
zeropoint for each cameras 1 and 2, in 1.0mm steps. For NIC3 we step
from -0.5mm to -9.5mm relative to mechanical zero, in steps of 1.0mm.
d) Use PAM X/Y tilt and OTA offset slew compensations refined from
previous focus monitoring/optical alignment activities.
NIC1/NIC2/NIC3 11319
NICMOS Photometric Stability Monitoring
This NICMOS calibration proposal carries out photometric monitoring
observations during Cycle 15. The format is the same as the Cycle 14
version of the program (10725), but a few modifications were made with
respect to the Cycle 12 program 9995 and Cycle 13 program 10381.
Provisions had to be made to adopt to 2-gyro mode (G191B2B was added
as extra target to provide target visibility through most of the
year). Where before 4 or 7 dithers were made in a filter before we
moved to the next filter, now we observe all filters at one position
before moving to the next dither position. While the previous method
was chosen to minimize the effect of persistence, we now realize that
persistence may be connected to charge trapping and by moving through
the filter such that the count rate increases, we reach equilibrium
more quickly between charge being trapped and released. We have also
increased exposure times where possible to reduce the charge trapping
non-linearity effects.
WFPC2 11229
SEEDS: The Search for Evolution of Emission from Dust in Supernovae
with HST and Spitzer
The role that massive stars play in the dust content of the Universe
is extremely uncertain. It has long been hypothesized that dust can
condense within the ejecta of supernovae {SNe}, however there is a
frustrating discrepancy between the amounts of dust found in the early
Universe, or predicted by nucleation theory, and inferred from SN
observations. Our SEEDS collaboration has been carefully revisiting
the observational case for dust formation by core- collapse SNe, in
order to quantify their role as dust contributors in the early
Universe. As dust condenses in expanding SN ejecta, it will increase
in optical depth, producing three simultaneously observable phenomena:
{1} increasing optical extinction; {2} infrared {IR} excesses; and {3}
asymmetric blue-shifted emission lines. Our SEEDS collaboration
recently reported all three phenomena occurring in SN2003gd,
demonstrating the success of our observing strategy, and permitting us
to derive a dust mass of up to 0.02 solar masses created in the SN. To
advance our understanding of the origin and evolution of the
interstellar dust in galaxies, we propose to use HST's WFPC2 and
NICMOS instruments plus Spitzer's photometric instruments to monitor
ten recent core-collapse SNe for dust formation and, as a bonus,
detect light echoes that can affect the dust mass estimates. These
space-borne observations will be supplemented by ground-based
spectroscopic monitoring of their optical emission line profiles.
These observations would continue our 2-year HST and Spitzer
monitoring of this phenomena in order to address two key questions: Do
all SNe produce dust? and How much dust do they produce? As all the SN
are within 15 Mpc, each SN stands an excellent chance of detection
with HST and Spitzer and of resolving potential light echoes.
FGS 11210
The Architecture of Exoplanetary Systems
Are all planetary systems coplanar? Concordance cosmogony makes that
prediction. It is, however, a prediction of extrasolar planetary
system architecture as yet untested by direct observation for main
sequence stars other than the Sun. To provide such a test, we propose
to carry out FGS astrometric studies on four stars hosting seven
companions. Our understanding of the planet formation process will
grow as we match not only system architecture, but formed planet mass
and true distance from the primary with host star characteristics for
a wide variety of host stars and exoplanet masses. We propose that a
series of FGS astrometric observations with demonstrated 1 millisecond
of arc per-observation precision can establish the degree of
coplanarity and component true masses for four extrasolar systems: HD
202206 {brown dwarf+planet}; HD 128311 {planet+planet}, HD 160691 = mu
Arae {planet+planet}, and HD 222404AB = gamma Cephei {planet+star}. In
each case the companion is identified as such by assuming that the
minimum mass is the actual mass. For the last target, a known stellar
binary system, the companion orbit is stable only if coplanar with the
AB binary orbit.
WFPC2 11202
The Structure of Early-type Galaxies: 0.1-100 Effective Radii
The structure, formation and evolution of early-type galaxies is still
largely an open problem in cosmology: how does the Universe evolve
from large linear scales dominated by dark matter to the highly
non-linear scales of galaxies, where baryons and dark matter both play
important, interacting, roles? To understand the complex physical
processes involved in their formation scenario, and why they have the
tight scaling relations that we observe today {e.g. the Fundamental
Plane}, it is critically important not only to understand their
stellar structure, but also their dark-matter distribution from the
smallest to the largest scales. Over the last three years the SLACS
collaboration has developed a toolbox to tackle these issues in a
unique and encompassing way by combining new non-parametric strong
lensing techniques, stellar dynamics, and most recently weak
gravitational lensing, with high-quality Hubble Space Telescope
imaging and VLT/Keck spectroscopic data of early-type lens systems.
This allows us to break degeneracies that are inherent to each of
these techniques separately and probe the mass structure of early-type
galaxies from 0.1 to 100 effective radii. The large dynamic range to
which lensing is sensitive allows us both to probe the clumpy
substructure of these galaxies, as well as their low-density outer
haloes. These methods have convincingly been demonstrated, by our
team, using smaller pilot-samples of SLACS lens systems with HST data.
In this proposal, we request observing time with WFPC2 and NICMOS to
observe 53 strong lens systems from SLACS, to obtain complete
multi-color imaging for each system. This would bring the total number
of SLACS lens systems to 87 with completed HST imaging and effectively
doubles the known number of galaxy-scale strong lenses. The deep HST
images enable us to fully exploit our new techniques, beat down
low-number statistics, and probe the structure and evolution of
early-type galaxies, not only with a uniform data-set an order of
magnitude larger than what is available now, but also with a fully
coherent and self-consistent methodological approach!
WEPC2 11196
An Ultraviolet Survey of Luminous Infrared Galaxies in the Local
Universe
At luminosities above 10^11.4 L_sun, the space density of far-infrared
selected galaxies exceeds that of optically selected galaxies. These
Luminous Infrared Galaxies {LIRGs} are primarily interacting or
merging disk galaxies undergoing starbursts and creating/fueling
central AGN. We propose far {ACS/SBC/F140LP} and near {WFPC2/PC/F218W}
UV imaging of a sample of 27 galaxies drawn from the complete IRAS
Revised Bright Galaxy Sample {RBGS} LIRGs sample and known, from our
Cycle 14 B and I-band ACS imaging observations, to have significant
numbers of bright {23 < B < 21 mag} star clusters in the central 30
arcsec. The HST UV data will be combined with previously obtained HST,
Spitzer, and GALEX images to {i} calculate the ages of the clusters as
function of merger stage, {ii} measure the amount of UV light in
massive star clusters relative to diffuse regions of star formation,
{iii} assess the feasibility of using the UV slope to predict the
far-IR luminosity {and thus the star formation rate} both among and
within IR-luminous galaxies, and {iv} provide a much needed catalog of
rest- frame UV morphologies for comparison with rest-frame UV images
of high-z LIRGs and Lyman Break Galaxies. These observations will
achieve the resolution required to perform both detailed photometry of
compact structures and spatial correlations between UV and redder
wavelengths for a physical interpretation our IRX-Beta results. The
HST UV data, combined with the HST ACS, Spitzer, Chandra, and GALEX
observations of this sample, will result in the most comprehensive
study of luminous starburst galaxies to date.
NIC1/NIC2 11139
NICMOS Observations of the Microquasar GRS 1758-258
The galactic black hole candidate GRS 1758-258 is normally one of the
brightest persistent gamma-ray sources in the vicinity of the galactic
center. It is a microquasar with relativistic radio jets emanating
from a central variable source. Microquasars are excellent nearby test
laboratories for studying the complex accretion and outflow processes
that take place near black hole horizons. Despite an accurate location
provided by Chandra and the VLA and over a decade of careful
ground-based studies, the optical/infrared counterpart to GRS 1758-258
remains unknown. A stellar counterpart is expected, but the current
candidates are all more than 2 sigma from the center of the error
circle. The ground-based infrared flux limits are also right at the
values expected for the synchrotron emission from the outflow from the
black hole, and possibly for the emission from the accretion disk.
This leaves open the question as to what is powering this very
energetic persistent source. Here we propose to use NICMOS to perform
broad-band imaging of the GRS 1758- 258 error box. These images will
be more than three magnitudes more sensitive than the current
ground-based ones. The resulting spectra will reveal the thermal/non-
thermal nature of the sources in the region of the error box, and the
high spatial resolution images may reveal a jet structure. We propose
to perform three visits of two orbits each spanning the suggested
18.45 day binary orbital period of the system: a correct counterpart
identification should be confirmed by its variability. We will also
aim to support the HST observations with X- and gamma-ray observations
using Swift or INTEGRAL, and with longer wavelength observations from
the ground.
WFPC2 11122
Expanding PNe: Distances and Hydro Models
We propose to obtain repeat narrowband images of a sample of eighteen
planetary nebulae {PNe} which have HST/WFPC2 archival data spanning
time baselines of a decade. All of these targets have previous high
signal-to-noise WFPC2/PC observations and are sufficiently nearby to
have readily detectable expansion signatures after a few years. Our
main scientific objectives are {a} to determine precise distances to
these PNe based on their angular expansions, {b} to test detailed and
highly successful hydrodynamic models that predict nebular
morphologies and expansions for subsamples of round/elliptical and
axisymmetric PNe, and {c} to monitor the proper motions of nebular
microstructures in an effort to learn more about their physical nature
and formation mechanisms. The proposed observations will result in
high-precision distances to a healthy subsample of PNe, and from this
their expansion ages, luminosities, CSPN properties, and masses of
their ionized cores. With good distances and our hydro models, we will
be able to determine fundamental parameters {such as nebular and
central star masses, luminosity, age}. The same images allow us to
monitor the changing overall ionization state and to search for the
surprisingly non-homologous growth patterns to bright elliptical PNe
of the same sort seen by Balick & Hajian {2004} in NGC 6543.
Non-uniform growth is a sure sign of active pressure imbalances within
the nebula that require careful hydro models to understand.
NIC3 11120
A Paschen-Alpha Study of Massive Stars and the ISM in the Galactic
Center
The Galactic center (GC) is a unique site for a detailed study of a
multitude of complex astrophysical phenomena, which may be common to
nuclear regions of many galaxies. Observable at resolutions
unapproachable in other galaxies, the GC provides an unparalleled
opportunity to improve our understanding of the interrelationships of
massive stars, young stellar clusters, warm and hot ionized gases,
molecular clouds, large scale magnetic fields, and black holes. We
propose the first large-scale hydrogen Paschen alpha line survey of
the GC using NICMOS on the Hubble Space Telescope. This survey will
lead to a high resolution and high sensitivity map of the Paschen
alpha line emission in addition to a map of foreground extinction,
made by comparing Paschen alpha to radio emission. This survey of the
inner 75 pc of the Galaxy will provide an unprecedented and complete
search for sites of massive star formation. In particular, we will be
able to (1) uncover the distribution of young massive stars in this
region, (2) locate the surfaces of adjacent molecular clouds, (3)
determine important physical parameters of the ionized gas, (4)
identify compact and ultra-compact HII regions throughout the GC. When
combined with existing Chandra and Spitzer surveys as well as a wealth
of other multi-wavelength observations, the results will allow us to
address such questions as where and how massive stars form, how
stellar clusters are disrupted, how massive stars shape and heat the
surrounding medium, and how various phases of this medium are
interspersed.
WFPC2 11113
Binaries in the Kuiper Belt: Probes of Solar System Formation and
Evolution
The discovery of binaries in the Kuiper Belt and related small body
populations is powering a revolutionary step forward in the study of
this remote region. Three quarters of the known binaries in the Kuiper
Belt have been discovered with HST, most by our snapshot surveys. The
statistics derived from this work are beginning to yield surprising
and unexpected results. We have found a strong concentration of
binaries among low-inclination Classicals, a possible size cutoff to
binaries among the Centaurs, an apparent preference for nearly equal
mass binaries, and a strong increase in the number of binaries at
small separations. We propose to continue this successful program in
Cycle 16; we expect to discover at least 13 new binary systems,
targeted to subgroups where these discoveries can have the greatest
impact.
WFPC2 11111
A Search for an Intermediate Mass Black Hole in the Globular Cluster
NGC 6266
We propose to search for an intermediate mass black hole (IMBH) in the
core of the galactic globular cluster NGC 6266. Based on a comparison
between the observed central surface brightness profiles of 38
globular clusters and state-of-the art N- body simulations, NGC 6266
offers the best hope of detecting an IMBH among these objects. This
detection would be significant for at least two reasons. It would be
the first concrete discovery of an IMBH, revealing unique information
about the environment in which these objects form, and second, its
discovery would provide a powerful validation on the N-body
simulations used to track the dynamical evolution of globular
clusters.
WFPC2 11083
The Structure, Formation and Evolution of Galactic Cores and Nuclei
A surprising result has emerged from the ACS Virgo Cluster Survey
{ACSVCS}, a program to obtain ACS/WFC gz imaging for a large, unbiased
sample of 100 early-type galaxies in the Virgo Cluster. On
subarcsecond scales {i.e., <0.1"-1"}, the HST brightness profiles vary
systematically from the brightest giants {which have nearly constant
surface brightness cores} to the faintest dwarfs {which have compact
stellar nuclei}. Remarkably, the fraction of galaxy mass contributed
by the nuclei in the faint galaxies is identical to that contributed
by supermassive black holes in the bright galaxies {0.2%}. These
findings strongly suggest that a single mechanism is responsible for
both types of Central Massive Object: most likely internally or
externally modulated gas inflows that feed central black holes or lead
to the formation of "nuclear star clusters". Understanding the history
of gas accretion, star formation and chemical enrichment on
subarcsecond scales has thus emerged as the single most pressing
question in the study of nearby galactic nuclei, either active or
quiescent. We propose an ambitious HST program {199 orbits} that
constitutes the next, obvious step forward: high-resolution,
ultraviolet {WFPC2/F255W} and infrared {NIC1/F160W} imaging for the
complete ACSVCS sample. By capitalizing on HST's unique ability to
provide high-resolution images with a sharp and stable PSF at UV and
IR wavelengths, we will leverage the existing optical HST data to
obtain the most complete picture currently possible for the history of
star formation and chemical enrichment on these small scales. Equally
important, this program will lead to a significant improvement in the
measured structural parameters and density distributions for the
stellar nuclei and the underlying galaxies, and provide a sensitive
measure of "frosting" by young stars in the galaxy cores. By virtue of
its superb image quality and stable PSF, NICMOS is the sole instrument
capable of the IR observations proposed here. In the case of the WFPC2
observations, high-resolution UV imaging {< 0.1"} is a capability
unique to HST, yet one that could be lost at any time.
WFPC2 11029
WFPC2 CYCLE 15 Intflat Linearity Check and Filter Rotation Anomaly
Monitor
Intflat observations will be taken to provide a linearity check: the
linearity test consists of a series of intflats in F555W, in each gain
and each shutter. A combination of intflats, visflats, and earthflats
will be used to check the repeatability of filter wheel motions.
{Intflat sequences tied to decons, visits 1-18 in prop 10363, have
been moved to the cycle 15 decon proposal xxxx for easier scheduling.}
Note: long-exposure WFPC2 intflats must be scheduled during ACS
anneals to prevent stray light from the WFPC2 lamps from contaminating
long ACS external exposures.
WFPC2 10916
A Study of SN Ejecta in the Core-Collapse Supernova Remnant
G292.0+1.8: Cas A's Older Cousin
Recent studies of the southern oxygen-rich supernova remnant {SNR}
G292.0+1.8 have shown it to be the only Galactic SNR to exhibit all
the features we expect in young remnants of core- collapse supernovae:
an outer shell behind an expanding primary shock, high-velocity
fragments of undiluted metal-rich ejecta, and a central pulsar
surrounded by a pulsar-wind nebula. G292.0+1.8's optical emission
consists of numerous knots and filaments of O- and S-rich ejecta
spread throughout much of the remnant shell, many with radially
oriented pencil-like geometries that may trace their origins to
Rayleigh-Taylor instabilities during the SN event. The evolution and
fine-scale structure of SN debris in young remnants is poorly
understood and largely uncharted territory. For testing models for the
distribution of metal-rich ejecta from core-collapse SNe, how the
ejecta evolve and clump, and how SN shocks interact with the local
circumstellar medium, the 3000-yr-old G292.0+1.8 remnant rivals the
320-yr-old Cas A remnant in importance. We therefore propose the first
HST images of G292.0+1.8 in order to characterize the fine-scale
spatial distribution of the ejecta, their sub-arcsecond chemical
make-up, and the detailed structure and scale lengths for metal-rich
SN ejecta clumps. The proposed HST images of G292.0+1.8 will be used
in conjunction with existing Spitzer Cycle 1 infrared data and an
upcoming 0.5 Msec Chandra X-ray image. We expect to achieve the same
kind of results for G292 that have already been obtained for Cas A.
High-resolution HST images of this remnant, combined with Spitzer and
Chandra data and contrasted with a similar data set on Cas A, will
provide superb multiwavelength benchmarks for both very young and
older core-collapse SNRs.
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: (None)
COMPLETED OPS NOTES: (None)
SCHEDULED SUCCESSFUL
FGS GSacq 24 24
FGS REacq 16 16
OBAD with Maneuver 78 78
SIGNIFICANT EVENTS:
Battery SOC Modifications Flash Report:
At approximately 2008/094 13:32 GMT (9:32 am local), BM SOC, SOC1,
SOC2 and PSI Test Limits were successfully increased by 10Ah via OPS
request 18220. Ground limits for the battery pressures and FSW SOC
were also updated via OPS note 1682. EPS SEs observed the expected FSW
SOC increase upon uplink of the new value. Nominal system performance
was observed for the rest of the EPS system.