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Daily Report #4963



 
 
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Old November 2nd 09, 05:45 PM posted to sci.astro.hubble
Cooper, Joe
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Default Daily Report #4963

HUBBLE SPACE TELESCOPE - Continuing to Collect World Class Science

DAILY REPORT #4963

PERIOD COVERED: 5am October 30 - 5am November 2, 2009 (DOY 303/09:00z-306/10:00z)

OBSERVATIONS SCHEDULED

COS/FUV 11997

FUV Internal/External Wavelength Scale Monitor

This program monitors the offsets between the wavelength scale set by
the internal wavecal versus that defined by absorption lines in
external targets. This is accomplished by observing two external
targets in the SMC: SK191 with G130M and G160M and Cl* NGC 330 ROB B37
with G140L (SK191 is too bright to be observed with G140L). The
cenwaves observed in this program are a subset of the ones used during
Cycle 17. Observing all cenwaves would require a considerably larger
number of orbits. Constraints on scheduling of each target are placed
so that each target is observed once every ~2-3 months. Observing the
two targets every month would also require a considerably larger
number of orbits.

WFC3/IR/S/C 11929

IR Dark Current Monitor

Analyses of ground test data showed that dark current signals are more
reliably removed from science data using darks taken with the same
exposure sequences as the science data, than with a single dark
current image scaled by desired exposure time. Therefore, dark current
images must be collected using all sample sequences that will be used
in science observations. These observations will be used to monitor
changes in the dark current of the WFC3-IR channel on a day-to-day
basis, and to build calibration dark current ramps for each of the
sample sequences to be used by GOs in Cycle 17. For each sample
sequence/array size combination, a median ramp will be created and
delivered to the calibration database system (CDBS).

WFC3/IR 11926

IR Zero Points

We will measure and monitor the zeropoints through the IR filters
using observations of the white dwarf standard stars, GD153, GD71 and
GD191B2B and the solar analog standard star, P330E. Data will be taken
monthly during Cycle 17. Observations of the star cluster, NGC 104,
are made twice to check color transformations. We expect an accuracy
of 2% in the wide filter zeropoints relative to the HST photometric
system, and 5% in the medium- and narrow-band filters.

WFC3/UV 11923

UVIS Filter Wedge Check

The position of each UVIS filter will be checked to verify that the
filters meet the CEI (Contract End Item) specification for image
displacement. We will observe NGC 1850 with all full-frame UVIS
filters using a subarray (UVIS1-C512A) without moving the telescope,
as well as the quad filters with a 512x512 specifically designed
subarray. We will also acquire one grism exposure. The relative
displacement of the stars in each image will be measured from one
filter to the next.

WFC3/UVIS 11908

Cycle 17: UVIS Bowtie Monitor

Ground testing revealed an intermittent hysteresis type effect in the
UVIS detector (both CCDs) at the level of ~1%, lasting hours to days.
Initially found via an unexpected bowtie-shaped feature in flatfield
ratios, subsequent lab tests on similar e2v devices have since shown
that it is also present as simply an overall offset across the entire
CCD, i.e., a QE offset without any discernable pattern. These lab
tests have further revealed that overexposing the detector to count
levels several times full well fills the traps and effectively
neutralizes the bowtie. Each visit in this proposal acquires a set of
three 3x3 binned internal flatfields: the first unsaturated image will
be used to detect any bowtie, the second, highly exposed image will
neutralize the bowtie if it is present, and the final image will allow
for verification that the bowtie is gone.

WFC3/UVIS 11907

UVIS Cycle 17 Contamination Monitor

The UV throughput of WFC3 during Cycle 17 is monitored via weekly
standard star observations in a subset of key filters covering
200-600nm and F606W, F814W as controls on the red end. The data will
provide a measure of throughput levels as a function of time and
wavelength, allowing for detection of the presence of possible
contaminants.

WFC3/UVIS 11905

WFC3 UVIS CCD Daily Monitor

The behavior of the WFC3 UVIS CCD will be monitored daily with a set
of full-frame, four-amp bias and dark frames. A smaller set of 2Kx4K
subarray biases are acquired at less frequent intervals throughout the
cycle to support subarray science observations. The internals from
this proposal, along with those from the anneal procedure (Proposal
11909), will be used to generate the necessary superbias and superdark
reference files for the calibration pipeline (CDBS).

ACS/WFC3 11887

CCD Stability Monitor

This program will verify that the low frequency flat fielding, the
photometry, and the geometric distortion are stable in time and across
the field of view of the CCD arrays. A moderately crowded stellar
field in the cluster 47 Tuc is observed with the ACS (at the cluster
core) and WFC3 (6 arcmin West of the cluster core) using the full
suite of broad and narrow band imaging filters. The positions and
magnitudes of objects will be used to monitor local and large scale
variations in the plate scale and the sensitivity of the detectors and
to derive an independent measure of the detector CTE. The UV
sensitivity for the SBC and ACS will be addressed in the UV
contamination monitor program (11886, PI=Smith).

One additional orbit will be obtained at the beginning of the cycle
will allow a verification of the CCD gain ratios for WFC3 using gain
2.0, 1.4, 1.0, 0.5 and for ACS using gain 4.0 and 2.0. In addition,
one subarray exposure with the WFC3 will allow a verification that
photometry obtained in full-frame and in sub-array modes are
repeatable to better than 1%. This test is important for the ACS
Photometric Cross-Calibration program (11889, PI=Bohlin) which uses
sub-array exposures.

ACS/WFC3 11879

CCD Daily Monitor (Part 1)

This program comprises basic tests for measuring the read noise and
dark current of the ACS WFC and for tracking the growth of hot pixels.
The recorded frames are used to create bias and dark reference images
for science data reduction and calibration. This program will be
executed four days per week (Mon, Wed, Fri, Sun) for the duration of
Cycle 17. To facilitate scheduling, this program is split into three
proposals. This proposal covers 352 orbits (22 weeks) from 31 August
2009 to 31 January 2010.

STIS/MA 11863

STIS MAMA Fold Distribution

The performance of MAMA microchannel plates can be monitored using a
MAMA fold analysis procedure. The fold analysis provides a measurement
of the distribution of charge cloud sizes incident upon the anode
giving some measure of changes in the pulse-height distribution of the
MCP and, therefore, MCP gain. This proposal executes the same steps as
the STIS MAMA Fold Analysis (10035) during Cycle 12.

STIS/CCD 11846

CCD Bias Monitor-Part 1

The purpose of this proposal is to monitor the bias in the 1x1, 1x2,
2x1, and 2x2 bin settings at gain=1, and 1x1 at gain = 4, to build up
high-S/N superbiases and track the evolution of hot columns.

STIS/CCD 11844

CCD Dark Monitor Part 1

The purpose of this proposal is to monitor the darks for the STIS CCD.

FGS 11788

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.

WFC3/UVIS 11732

The Temperature Profiles of Quasar Accretion Disks

We can now routinely measure the size of quasar accretion disks using
gravitational microlensing of lensed quasars. At optical wavelengths
we observe a size and scaling with black hole mass roughly consistent
with thin disk theory but the sizes are larger than expected from the
observed optical fluxes. One solution would be to use a flatter
temperature profile, which we can study by measuring the wavelength
dependence of the disk size over the largest possible wavelength
baseline. Thus, to understand the size discrepancy and to probe closer
to the inner edge of the disk we need to extend our measurements to UV
wavelengths, and this can only be done with HST. For example, in the
UV we should see significant changes in the optical/UV size ratio with
black hole mass. We propose monitoring 5 lenses spanning a broad range
of black hole masses with well-sampled ground based light curves,
optical disk size measurements and known GALEX UV fluxes during Cycles
17 and 18 to expand from our current sample of two lenses. We would
obtain 5 observations of each target in each Cycle, similar to our
successful strategy for the first two targets.

STIS/CCD 11721

Verifying the Utility of Type Ia Supernovae as Cosmological Probes:
Evolution and Dispersion in the Ultraviolet Spectra

The study of distant type Ia supernova (SNe Ia) offers the most
practical and immediate discriminator between popular models of dark
energy. Yet fundamental questions remain over possible
redshift-dependent trends in their observed and intrinsic properties.
High-quality Keck spectroscopy of a representative sample of 36
intermediate redshift SNe Ia has revealed a surprising, and
unexplained, diversity in their rest-frame UV fluxes. One possible
explanation is hitherto undiscovered variations in the progenitor
metallicity. Unfortunately, this result cannot be compared to local UV
data as only two representative SNe Ia have been studied near maximum
light. Taking advantage of two new `rolling searches' and the
restoration of STIS, we propose a non-disruptive TOO campaign to
create an equivalent comparison local sample. This will allow us to
address possible evolution in the mean UV spectrum and its diversity,
an essential precursor to the study of SNe beyond z~1.

ACS/WFC 11689

Direct Observations of Dark Matter from a Second Bullet: The
Spectacular Abell 2744

Vigorous cluster mergers provide a unique opportunity to directly
"see" dark matter and to probe its properties through the analysis of
the segregation of the baryonic and non-baryonic components. This is
accomplished through detailed comparison of the mass distributions as
traced by X-ray emitting gas and by gravitational lensing. This
condition is rare and so far only one cluster has met these
requirements, the so-called "bullet" cluster, producing exciting
results and placing constraints to the properties of dark matter.
These constraints have a broad impact on models for formation of
structure and on galaxy evolution. This multi-wavelength analysis has
the potential confront alternative gravity models such as MOND.
Therefore, it is crucial to find new bullet clusters to corroborate
and improve previous measurements. This is the most direct way to
constrain dark matter properties and A2744 is ideal for corroborating
this study since it maximizes all the requirements for this analysis.
Here, we propose to carry out such analysis through combined ACS and
Chandra observations of the cluster merger Abell 2744.

WFC3/UV/ACS/WFC 11688

Exploring the Bottom End of the White Dwarf Cooling Sequence in the
Open Cluster NGC6819

The recent discovery by our group of an unexpectedly bright end of the
white-dwarf (WD) luminosity function (LF) of the metal-rich, old open
cluster NGC 6791 casts serious doubts on our understanding of the
physical process which rules the formation and the cooling of WDs. It
is clear at this point that the theory badly needs more observations.
Here we propose WFC3/UVIS and ACS/WFC HST observations reaching the
bottom end of the WD LF, for the first time in a solar-metallicity,
2.5-Gyr-old, populous open cluster: NGC 6819.

ACS/WFC3 11670

The Host Environments of Type Ia Supernovae in the SDSS Survey

The Sloan Digital Sky Survey Supernova Survey has discovered nearly
500 type Ia supernovae and created a large, unique, and uniform sample
of these cosmological tools. As part of a comprehensive study of the
supernova hosts, we propose to obtain Hubble ACS images of a large
fraction of these galaxies. Integrated colors and spectra will be
measured from the ground, but we require high-resolution HST imaging
to provide accurate morphologies and color information at the site of
the explosion. This information is essential in determining the
systematic effects of population age on type Ia supernova luminosities
and improving their reliability in measuring dark energy. Recent
studies suggest two populations of type Ia supernovae: a class that
explodes promptly after star-formation and one that is delayed by
billions of years. Measuring the star-formation rate at the site of
the supernova from colors in the HST images may be the best way to
differentiate between these classes.

WFC3/IR 11666

Chilly Pairs: A Search for the Latest-type Brown Dwarf Binaries and
the Prototype Y Dwarf

We propose to use HST/NICMOS to image a sample of 27 of the nearest (
20 pc) and lowest luminosity T-type brown dwarfs in order to identify
and characterize new very low mass binary systems. Only 3 late-type T
dwarf binaries have been found to date, despite that fact that these
systems are critical benchmarks for evolutionary and atmospheric
models at the lowest masses. They are also the most likely systems to
harbor Y dwarf companions, an as yet unpopulated putative class of
very cold (T 600 K) brown dwarfs. Our proposed program will more
than double the number of T5-T9 dwarfs imaged at high resolution, with
an anticipated yield of ~5 new binaries with initial characterization
of component spectral types. We will be able to probe separations
sufficient to identify systems suitable for astrometric orbit and
dynamical mass measurements. We also expect one of our discoveries to
contain the first Y-type brown dwarf. Our proposed program complements
and augments ongoing ground-based adaptive optics surveys and provides
pathway science for JWST.

WFC3/UVIS/IR 11644

A Dynamical-Compositional Survey of the Kuiper Belt: A New Window Into
the Formation of the Outer Solar System

The eight planets overwhelmingly dominate the solar system by mass,
but their small numbers, coupled with their stochastic pasts, make it
impossible to construct a unique formation history from the dynamical
or compositional characteristics of them alone. In contrast, the huge
numbers of small bodies scattered throughout and even beyond the
planets, while insignificant by mass, provide an almost unlimited
number of probes of the statistical conditions, history, and
interactions in the solar system. To date, attempts to understand the
formation and evolution of the Kuiper Belt have largely been dynamical
simulations where a hypothesized starting condition is evolved under
the gravitational influence of the early giant planets and an attempt
is made to reproduce the current observed populations. With little
compositional information known for the real Kuiper Belt, the test
particles in the simulation are free to have any formation location
and history as long as they end at the correct point. Allowing
compositional information to guide and constrain the formation,
thermal, and collisional histories of these objects would add an
entire new dimension to our understanding of the evolution of the
outer solar system. While ground based compositional studies have hit
their flux limits already with only a few objects sampled, we propose
to exploit the new capabilities of WFC3 to perform the first ever
large-scale dynamical-compositional study of Kuiper Belt Objects
(KBOs) and their progeny to study the chemical, dynamical, and
collisional history of the region of the giant planets. The
sensitivity of the WFC3 observations will allow us to go up to two
magnitudes deeper than our ground based studies, allowing us the
capability of optimally selecting a target list for a large survey
rather than simply taking the few objects that can be measured, as we
have had to do to date. We have carefully constructed a sample of 120
objects which provides both overall breadth, for a general
understanding of these objects, plus a large enough number of objects
in the individual dynamical subclass to allow detailed comparison
between and within these groups. These objects will likely define the
core Kuiper Belt compositional sample for years to come. While we have
many specific results anticipated to come from this survey, as with
any project where the field is rich, our current knowledge level is
low, and a new instrument suddenly appears which can exploit vastly
larger segments of the population, the potential for discovery -- both
anticipated and not -- is extraordinary.

COS/FUV 11625

Beyond the Classical Paradigm of Stellar Winds: Investigating
Clumping, Rotation and the Weak Wind Problem in SMC O Stars

SMC O stars provide an unrivaled opportunity to probe star formation,
evolution, and the feedback of massive stars in an environment similar
to the epoch of the peak in star formation history. Two recent
breakthroughs in the study of hot, massive stars have important
consequences for understanding the chemical enrichment and buildup of
stellar mass in the Universe. The first is the realization that
rotation plays a major role in influencing the evolution of massive
stars and their feedback on the surrounding environment. The second is
a drastic downward revision of the mass loss rates of massive stars
coming from an improved description of their winds. STIS spectroscopy
of SMC O stars combined with state-of-the-art NLTE analyses has shed
new light on these two topics. A majority of SMC O stars reveal
CNO-cycle processed material brought at their surface by rotational
mixing. Secondly, the FUV wind lines of early O stars provide strong
indications of the clumped nature of their wind. Moreover, we first
drew attention to some late-O dwarfs showing extremely weak wind
signatures. Consequently, we have derived mass loss rates from STIS
spectroscopy that are significantly lower than the current theoretical
predictions used in evolutionary models. Because of the limited size
of the current sample (and some clear bias toward stars with
sharp-lined spectra), these results must however be viewed as
tentative. Thanks to the high efficiency of COS in the FUV range, we
propose now to obtain high-resolution FUV spectra with COS of a larger
sample of SMC O stars to study systematically rotation and wind
properties of massive stars at low metallicity. The analysis of the
FUV wind lines will be based on our 2D extension of CMFGEN to model
axi-symmetric rotating winds.

WFC3/UVIS 11594

A WFC3 Grism Survey for Lyman Limit Absorption at z=2

We propose to conduct a spectroscopic survey of Lyman limit absorbers
at redshifts 1.8 z 2.5, using WFC3 and the G280 grism. This
proposal intends to complete an approved Cycle 15 SNAP program
(10878), which was cut short due to the ACS failure. We have selected
64 quasars at 2.3 z 2.6 from the Sloan Digital Sky Survey
Spectroscopic Quasar Sample, for which no BAL signature is found at
the QSO redshift and no strong metal absorption lines are present at z
2.3 along the lines of sight. The survey has three main

observational goals. First, we will determine the redshift frequency
dn/dz of the LLS over the column density range 16.0 log(NHI) 20.3
cm^-2. Second, we will measure the column density frequency
distribution f(N) for the partial Lyman limit systems (PLLS) over the
column density range 16.0 log(NHI) 17.5 cm^-2. Third, we will
identify those sightlines which could provide a measurement of the
primordial D/H ratio. By carrying out this survey, we can also help
place meaningful constraints on two key quantities of cosmological
relevance. First, we will estimate the amount of metals in the LLS
using the f(N), and ground based observations of metal line
transitions. Second, by determining f(N) of the PLLS, we can constrain
the amplitude of the ionizing UV background at z~2 to a greater
precision. This survey is ideal for a snapshot observing program,
because the on-object integration times are all well below 30 minutes,
and follow-up observations from the ground require minimal telescope
time due to the QSO sample being bright.

WFC3/UV 11589

Hypervelocity Stars as Unique Probes of the Galactic Center and Outer
Halo

We propose to obtain high-resolution images of 11 new hypervelocity
stars in the Galactic halo in order to establish the first-epoch
astrometric frame, as a part of a long-term program to measure precise
proper motions in an absolute inertial frame. The origin of these
recently discovered stars with extremely large positive radial
velocities, in excess of the escape speed from the Galaxy, is
consistent only with being ejected from the deep potential well of the
massive black hole at the Galactic center. Reconstructing the full
three-dimensional space motion of the hypervelocity stars, through
astrometric proper motions, provides a unique opportunity to measure
the shape and orientation of the triaxial dark matter halo. The
hypervelocity stars allow determination of the Galactic potential out
to 120 kpc, independently of and at larger distances than is afforded
by tidal streams of satellite galaxies such as the Sagittarius dSph
galaxy. Proper motions of the full set of hypervelocity stars will
provide unique constraints on massive star formation in the
environment of the Galactic center and on the history of stellar
ejection by the supermassive black hole. We request one orbit with
WFC3 for each of the 11 hypervelocity stars to establish their current
positions relative to background galaxies. We request a repeated
observation of these stars in Cycle 19, which will conclusively
measure the astrometric proper motions.

STIS/CCD 11572

Charaterizing Atmospheric Sodium in the Transiting hot-Jupiter
HD189733b

We propose STIS transit observations of the exoplanet HD189733b with
the goal of measuring atmospheric atomic sodium. Our strategy is to
repeat the observing meathods used for HD209458b, which resulted in a
successful exoplanetary atmospheric sodium detection. Initial
ground-based measurements suggest that the sodium signature on
HD189733 could be up to three times larger than HD209458b, making a
robust 8? detection possible within a 12 orbit program observing three
transits. Transit transmission spectra resulting from space-based
measurements have the advantage of retaining absolute transit depths
when features are measured, which will make it possible to provide an
observational link between sodium and atmospheric haze detected with
ACS. Such a link can break modeling degeneracies and providing
stringent constraints on the overall atmospheric properties, making
such atmospheric information as abundances and the
temperature-pressure-altitude relation known. A successful measurement
will also allow for comparative atmospheric exoplanetology, as an
atmospheric feature will be measured with the same instrument in two
separate planets.

STIS/CCD 11567

Boron Abundances in Rapidly Rotating Early-B Stars

Models of rotation in early-B stars predict that rotationally driven
mixing should deplete surface boron abundances during the
main-sequence lifetime of many stars. However, recent work has shown
that many boron depleted stars are intrinsically slow rotators for
which models predict no depletion should have occurred, while
observations of nitrogen in some more rapidly rotating stars show less
mixing than the models predict. Boron can provide unique information
on the earliest stages of mixing in B stars, but previous surveys have
been biased towards narrow- lined stars because of the difficulty in
measuring boron abundances in rapidly rotating stars. The two targets
observed as part of our Cycle 13 SNAP program 10175, just before STIS
failed, demonstrate that it is possible to make useful boron abundance
measurements for early-B stars with Vsin(i) above 100 km/s. We propose
to extend that survey to a large enough sample of stars to allow
statistically significant tests of models of rotational mixing in
early-B stars.

WFC3/UVIS 11565

A Search for Astrometric Companions to Very Low-Mass, Population II
Stars

We propose to carry out a Snapshot search for astrometric companions
in a subsample of very low-mass, halo subdwarfs identified within 120
parsecs of the Sun. These ultra-cool M subdwarfs are local
representatives of the lowest-mass H burning objects from the Galactic
Population II. The expected 3-4 astrometric doubles that will be
discovered will be invaluable in that they will be the first systems
from which gravitational masses of metal-poor stars at the bottom of
the main sequence can be directly measured.

NIC2/WFC3/IR 11548

Infrared Imaging of Protostars in the Orion A Cloud: The Role of
Environment in Star Formation

We propose NICMOS and WFC3/IR observations of a sample of 252
protostars identified in the Orion A cloud with the Spitzer Space
Telescope. These observations will image the scattered light escaping
the protostellar envelopes, providing information on the shapes of
outflow cavities, the inclinations of the protostars, and the overall
morphologies of the envelopes. In addition, we ask for Spitzer time to
obtain 55-95 micron spectra of 75 of the protostars. Combining these
new data with existing 3.6 to 70 micron photometry and forthcoming
5-40 micron spectra measured with the Spitzer Space Telescope, we will
determine the physical properties of the protostars such as envelope
density, luminosity, infall rate, and outflow cavity opening angle. By
examining how these properties vary with stellar density (i.e.
clusters vs. groups vs. isolation) and the properties of the
surrounding molecular cloud; we can directly measure how the
surrounding environment influences protostellar evolution, and
consequently, the formation of stars and planetary systems.
Ultimately, this data will guide the development of a theory of
protostellar evolution.

COS/FUV 11524

COS-GTO: WARM AND HOT ISM IN AND NEAR THE MILKY WAY

COS G130M and G160M 20, 000 resolution observations will be obtained
for 10 AGNs situated beyond Milky Way high velocity clouds. For all
objects good O VI line profile observations exist from FUSE and high
velocity O VI is detected. The COS observations will be used to obtain
high quality absorption line profiles (S/N ~ 30 to 40) for C IV, Si IV
and N V in the low and high velocity gas toward each AGN. The high
ionization profiles of O VI (from FUSE), N V, C IV, and Si IV will be
compared to low ionization profiles (O I, S II, Si II, Fe II, etc.) in
order to evaluate the physical conditions and origins of the highly
ionized gas in and near the Milky Way at low and high velocity. The
HVCs include Complex C (four lines of sight), Complex A, WD, WB, and
several negative velocity O VI HVCs. Other studies to be undertaken
with this data set include studies of the physical conditions and
abundances in the cool and warm HVC gas and studies of the physical
conditions in low redshift IGM systems detected along the 10 lines of
sight.

WFC3/ACS/UVIS 11360

Star Formation in Nearby Galaxies

Star formation is a fundamental astrophysical process; it controls
phenomena ranging from the evolution of galaxies and nucleosynthesis
to the origins of planetary systems and abodes for life. The WFC3,
optimized at both UV and IR wavelengths and equipped with an extensive
array of narrow-band filters, brings unique capabilities to this area
of study. The WFC3 Scientific Oversight Committee (SOC) proposes an
integrated program on star formation in the nearby universe which will
fully exploit these new abilities. Our targets range from the
well-resolved R136 in 30 Dor in the LMC (the nearest super star
cluster) and M82 (the nearest starbursting galaxy) to about half a
dozen other nearby galaxies that sample a wide range of star-formation
rates and environments. Our program consists of broad band
multiwavelength imaging over the entire range from the UV to the
near-IR, aimed at studying the ages and metallicities of stellar
populations, revealing young stars that are still hidden by dust at
optical wavelengths, and showing the integrated properties of star
clusters. Narrow-band imaging of the same environments will allow us
to measure star-formation rates, gas pressure, chemical abundances,
extinction, and shock morphologies. The primary scientific issues to
be addressed a (1) What triggers star formation? (2) How do the
properties of star-forming regions vary among different types of
galaxies and environments of different gas densities and compositions?
(3) How do these different environments affect the history of star
formation? (4) Is the stellar initial mass function universal or
determined by local conditions?

WFC3/IR 11208

The Co-Evolution of Spheroids and Black Holes in the Last Six Billion
Years

The masses of giant black holes are correlated with the luminosities,
masses, and velocity dispersions of the bulges of their host galaxies.
This empirical correlation of phenomena on widely different scales
(from pcs to kpcs) suggests that the formation and evolution of
galaxies and central black holes are closely linked. In Cycle 13, we
have started a campaign to map directly the co-evolution of spheroids
and black-holes by measuring in observationally favorable redshift
windows the empirical correlations connecting their properties. By
focusing on Seyfert 1s, where the nucleus and the stars contribute
comparable fractions of total light, black hole mass and bulge
dispersion are obtained from Keck spectroscopy. HST is required for
accurate measurement of the non-stellar AGN continuum, the morphology
of the galaxy, and the structural parameters of the bulge. The results
at z=0.36 indicate a surprisingly fast evolution of bulges in the past
4 Gyrs (significant at the 95%CL), in the sense that bulges were
significantly smaller for a given black hole mass. Also, the large
fraction of mergers and disturbed galaxies (4+2 out of 20) identifies
gas-rich mergers as the mechanisms responsible for bulge-growth. Going
to higher redshift - where evolutionary trends should be stronger - is
needed to confirm these tantalizing results. We propose therefore to
push our investigation to the next suitable redshift window z=0.57
(lookback-time 6 Gyrs). Fifteen objects are the minimum number
required to map the evolution of the empirical correlations between
bulge properties and black-hole mass, and to achieve a conclusive
detection of evolution (99%CL).

NIC1 11205

The Effects of Multiplicity on the Evolution of Young Stellar Objects:
A NICMOS Imaging Study

We propose to use NICMOS to investigate the multiplicity of young
stellar objects (YSOs) in the Orion B molecular cloud. Previous
observations with the Spitzer Space Telescope have revealed a
remarkable star forming filament near the NGC 2068 reflection nebula.
The population of YSOs associated with the filament exhibit a
surprisingly wide range of circumstellar evolutionary states, from
deeply embedded protostars to T Tauri accretion disks. Many of the
circumstellar disks themselves show evidence for significant dust
evolution, including grain growth and settling and cleared inner
holes, apparently in spite of the very young age of these stars. We
will estimate the binary fraction of a representative sample of
objects in these various stages of evolution in order to test whether
companions may play a significant role in that evolution.

FLIGHT OPERATIONS SUMMARY:

Significant Spacecraft Anomalies: (The following are preliminary
reports of potential non-nominal performance that will be
investigated.)

HSTARS:

12061 - GSAcq(1,2,1) scheduled at 304/23:27:17 resulted in fine lock
backup (1,0,1).

Observations possibly affected: WFC3 138 - 142 Proposal ID#11548, STIS
67 Proposal ID#11844, STIS 68-70 Proposal ID#11846, ACS 119 and 120
Proposal ID#11879

12062 - GSAcq(1,2,1) scheduled at 305/19:04:37z failed due to search
radius limits exceeded on both FGS1 and FGS2.

Observations affected: ACS 127-138, proposal ID#11887.

For Day 295 and 296
12059 - GSAcq(2,1,2) required two attempts to achieve CT-DV @
295/13:41:55
12060 - GSAcq(1,2,1) Lost Lock @ 296/17:18:55

COMPLETED OPS REQUEST: (None)

COMPLETED OPS NOTES: (None)

SCHEDULED SUCCESSFUL
FGS GSAcq 32 31
FGS REAcq 22 22
OBAD with Maneuver 15 15
LOSS of LOCK

SIGNIFICANT EVENTS: (None)


 




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