Daily Report #4972

HUBBLE SPACE TELESCOPE - Continuing to Collect World Class Science

DAILY REPORT #4972

PERIOD COVERED: 5am November 13 - 5am November 16, 2009 (DOY 317/10:00z-320/10:00z)

OBSERVATIONS SCHEDULED

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/UVIS/IR 11909

UVIS Hot Pixel Anneal

The on-orbit radiation environment of WFC3 will continually generate
new hot pixels. This proposal performs the procedure required for
repairing those hot pixels in the UVIS CCDs. During an anneal, the
two-stage thermo-electric cooler (TEC) is turned off and the
four-stage TEC is used as a heater to bring the UVIS CCDs up to ~20
deg. C. As a result of the CCD warmup, a majority of the hot pixels
will be fixed; previous instruments such as WFPC2 and ACS have seen
repair rates of about 80%. Internal UVIS exposures are taken before
and after each anneal, to allow an assessment of the procedure's
effectiveness in WFC3, provide a check of bias, global dark current,
and hot pixel levels, as well as support hysteresis (bowtie)
monitoring and CDBS reference file generation. One IR dark is taken
after each anneal, to provide a check of the IR detector.

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 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).

COS/FUV 11897

FUV Spectroscopic Sensitivity Monitoring

The purpose of this proposal is to monitor sensitivity in each FUV
grating mode to detect any changes due to contamination or other
causes.

ACS/WFC 11881

ACS internal CTE Monitor

The charge transfer efficiency (CTE) of the ACS CCD detectors will
decline as damage due to on-orbit radiation exposure accumulates. This
degradation will be closely monitored at regular intervals, because it
is likely to determine the useful lifetime of the CCDs. All the data
for this program is acquired using internal targets (lamps) only, so
all of the exposures should be taken during Earth occultation time
(but not during SAA passages). This program emulates the ACS
pre-flight ground calibration and post-launch SMOV testing (program
8948), so that results from each epoch can be directly compared.
Extended Pixel Edge Response (EPER) and First Pixel Response (FPR)
data will be obtained over a range of signal levels for both the Wide
Field Channel (WFC), and the High Resolution Channel (HRC).

ACS/WFC3/WFC 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/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.

WFC3/UV 11801

Black Holes in Globular Clusters

Search for 3000 solar mass black holes at the centers of three
Galactic globular clusters using stellar proper motions.

FGS 11789

An Astrometric Calibration of Population II Distance Indicators

In 2002, HST produced a highly precise parallax for RR Lyrae. That
measurement resulted in an absolute magnitude, M(V)= 0.61+/-0.11, a
useful result, judged by the over ten refereed citations each year
since. It is, however, unsatisfactory to have the direct,
parallax-based, distance scale of Population II variables based on a
single star. We propose, therefore, to obtain the parallaxes of four
additional RR Lyrae stars and two Population II Cepheids, or W Vir
stars. The Population II Cepheids lie with the RR Lyrae stars on a
common K-band Period-Luminosity relation. Using these parallaxes to
inform that relationship, we anticipate a zero-point error of 0.04
magnitude. This result should greatly strengthen confidence in the
Population II distance scale and increase our understanding of RR
Lyrae star and Pop. II Cepheid astrophysics.

WFC3/IR/ACS/WFC 11731

Studying Cepheid Systematics in M81: H-band Observations

The local value of the Hubble Constant remains one of the most
important constraints in cosmology, but improving on the 10% accuracy
of the HST Key Project is challenging. No improvements will be
convincing until the metallicity dependence is well constrained and
blending effects are fully understood. M81 and its dwarf companion
Holmberg IX are superb laboratories for studying Cepheid systematics
because they contain large numbers of bright Cepheids with a good
spread in metallicity lying at a common, relatively close distance. We
have identified 180 12P 70 day Cepheids in these two galaxies using
the Large Binocular Telescope (compared to 30 in total by the KP), and
will expand the sample further in 2008-2009. We will use 10 orbits
with WFC3/IR to obtain H-band images of 100 Cepheids in M81 to add to
the ACS/BVI calibrations we will obtain from archival data and 1 orbit
with WFC3/UVIS to add B-band data for Holmberg IX. Four band BVIH
photometry will allow us to flux calibrate, estimate extinction,
measure metallicity effects and then check the results in detail. We
can also examine blending effects on WFC3/IR data in a relatively
nearby galaxy before it is applied to more distant galaxies. Our M81
sample is three times larger than the next best sample, that of
NGC4258, and suffers less from blending because M81 is at half the
distance, so it is an excellent laboratory for studying Cepheid
systematics even if it lacks as precise a geometric distance as
NGC4258.

FGS 11704

The Ages of Globular Clusters and the Population II Distance Scale

Globular clusters are the oldest objects in the universe whose age can
be accurately determined. The dominant error in globular cluster age
determinations is the uncertain Population II distance scale. We
propose to use FGS 1R to obtain parallaxes with an accuracy of 0.2
milliarcsecond for 9 main sequence stars with [Fe/H] -1.5. This will
determine the absolute magnitude of these stars with accuracies of
0.04 to 0.06mag. This data will be used to determine the distance to
24 metal-poor globular clusters using main sequence fitting. These
distances (with errors of 0.05 mag) will be used to determine the ages
of globular clusters using the luminosity of the subgiant branch as an
age indicator. This will yield absolute ages with an accuracy of 5%,
about a factor of two improvement over current estimates. Coupled with
existing parallaxes for more metal-rich stars, we will be able to
accurately determine the age for globular clusters over a wide range
of metallicities in order to study the early formation history of the
Milky Way and provide an independent estimate of the age of the
universe.

The Hipparcos database contains only 1 star with [Fe/H] -1.4 and an
absolute magnitude error less than 0.18 mag which is suitable for use
in main sequence fitting. Previous attempts at main sequence fitting
to metal-poor globular clusters have had to rely on theoretical
calibrations of the color of the main sequence. Our HST parallax
program will remove this source of possible systematic error and yield
distances to metal-poor globular clusters which are significantly more
accurate than possible with the current parallax data. The HST
parallax data will have errors which are 10 times smaller than the
current parallax data. Using the HST parallaxes, we will obtain main
sequence fitting distances to 11 globular clusters which contain over
500 RR Lyrae stars. This will allow us to calibrate the absolute
magnitude of RR Lyrae stars, a commonly used Population II distance
indicator.

WFC3/UVIS 11657

The Population of Compact Planetary Nebulae in the Galactic Disk

We propose to secure narrow- and broad-band images of compact
planetary nebulae (PNe) in the Galactic Disk to study the missing link
of the early phases of post-AGB evolution. Ejected AGB envelopes
become PNe when the gas is ionized. PNe expand, and, when large
enough, can be studied in detail from the ground. In the interim, only
the HST capabilities can resolve their size, morphology, and central
stars. Our proposed observations will be the basis for a systematic
study of the onset of morphology. Dust properties of the proposed
targets will be available through approved Spitzer/IRS spectra, and so
will the abundances of the alpha- elements. We will be able thus to
explore the interconnection of morphology, dust grains, stellar
evolution, and populations. The target selection is suitable to
explore the nebular and stellar properties across the galactic disk,
and to set constraints on the galactic evolutionary models through the
analysis of metallicity and population gradients.

WFC3/UV 11646

Light Echoes as Probes of Supernova Type Ia Environments

Environmental factors of Type Ia supernovae are key in understanding
their nature, lightcurve evolution, and utility as cosmological
standard candles. The progenitor ages (and many other properties) are
bimodal, differing by roughly an order of magnitude. Is this reflected
as well in the differences in their immediate surroundings in terms of
gas and dust? The most powerful and direct way to address this issue
is by imaging the reflected light from the dust itself via a light
echo. In order for this approach to work, however, one must start
imaging the vicinity of the supernova frequently and soon after the
explosion is seen. We propose to maintain the imaging sequences
crucial for understanding the three-dimensional dust distribution of
two recent and key Type Ia supernovae, in a timely manner that will
prevent otherwise significant holes in our knowledge. These
observations are likely to be important in determining if the
interstellar versus the circumstellar environments are more important
in determining the appearance of Type Ia explosions, and thereby offer
a clue as to the poorly-understood mass-loss history of SN Ia
progenitors.

STIS/CCD 11611

Are Narrow-Line Seyfert 1 Galaxies Viewed Pole-on?

We will obtain spatially resolved spectra of 3 Narrow-Line Seyfert 1
galaxies (NLS1s) with the STIS G430M grating centered on the bright [O
III] emission lines. We will measure the radial velocities of the [O
III] lines across the narrow-line regions of these AGN and determine
the inclinations of their torus/accretion-disk axes via our kinematic
models. Our goal is to answer the following question: are NLS1s viewed
pole-on? If so, then the narrow widths of their permitted lines may be
due to geometric effects, rather than low black hole masses and
correspondingly high Eddington ratios as indicated by the currently
popular paradigm for NLS1s.

STIS/CCD 11606

Dynamical Hypermassive Black Hole Masses

We will use STIS spectra to derive the masses of 5 hypermassive black
holes (HMBHs). From the observed scaling relations defined by less
massive spheroids, these objects are expected to reside at the nuclei
of host galaxies with stellar velocity dispersions greater than 320
km/s. These 5 targets have confirmed regular gas distributions on the
scales of the black hole sphere of influence. It is essential that the
sphere of influence is resolved for accurate determinations of black
hole mass (0.1"). These scales cannot be effectively observed from the
ground. Only two HMBHs have had their masses modeled so far; it is
impossible to draw any general conclusions about the connections
between HMBH mass and their massive host galaxies. With these 5
targets we will determine whether these HMBHs deviate from the scaling
relations defined by less massive spheroids. A larger sample will
allow us to firmly anchor the high mass end of the correlation between
black hole mass and stellar velocity dispersion, and other scaling
relations. Therefore we are also conducting a SNAPshot program with
which we expect to detect a further 24 HMBH candidates for STIS
observation in future cycles. At the completion of this project we
will have populated the high mass end of the scaling relations with
the sample sizes enjoyed by less massive spheroids.

ACS/WFC3 11599

Distances of Planetary Nebulae from SNAPshots of Resolved Companions

Reliable distances to individual planetary nebulae (PNe) in the Milky
Way are needed to advance our understanding of their spatial
distribution, birthrates, influence on galactic chemistry, and the
luminosities and evolutionary states of their central stars (CSPN).
Few PNe have good distances, however. One of the best ways to remedy
this problem is to find resolved physical companions to the CSPN and
measure their distances by photometric main-sequence fitting. We have
previously used HST to identify and measure probable companions to 10
CSPN, based on angular separations and statistical arguments only. We
now propose to use HST to re-observe 48 PNe from that program for
which additional companions are possibly present. We then can use the
added criterion of common proper motion to confirm our original
candidate companions and identify new ones in cases that could not
confidently be studied before. We will image the region around each
CSPN in the V and I bands, and in some cases in the B band. Field
stars that appear close to the CSPN by chance will be revealed by
their relative proper motion during the 13+ years since our original
survey, leaving only genuine physical companions in our improved and
enlarged sample. This study will increase the number of Galactic PNe
with reliable distances by 50 percent and improve the distances to Pne
with previously known companions.

WFPC2 11593

Dynamical Masses of the Coolest Brown Dwarfs

T dwarfs are excellent laboratories to study the evolution and the
atmospheric physics of both brown dwarfs and extrasolar planets. To
date, only a single T dwarf binary has a dynamical mass determination,
and more are sorely needed. The prospects of measuring more dynamical
masses over the next decade are limited to 6 known short-period T
dwarf binaries. We propose here to obtain Long-Term HST/ACS monitoring
for the 3 of the 6 binaries which cannot be resolved with AO from the
ground. Upon completion, our program will substantially increase the
number of T dwarf dynamical mass measurements and thereby provide key
benchmarks for testing theoretical models of ultracool objects.

COS/FUV 11592

Testing the Origin(s) of the Highly Ionized High-Velocity Clouds: A
Survey of Galactic Halo Stars at z3 kpc

Cosmological simulation predicts that highly ionized gas plays an
important role in the formation and evolution of galaxies and their
interplay with the intergalactic medium. The NASA HST and FUSE
missions have revealed high-velocity CIV and OVI absorption along
extragalactic sightlines through the Galactic halo. These highly
ionized high-velocity clouds (HVCs) could cover 85% of the sky and
have a detection rate higher than the HI HVCs. Two competing, equally
exciting, theories may explain the origin of these highly ionized
HVCs: 1) the "Galactic" theory, where the HVCs are the result of
feedback processes and trace the disk-halo mass exchange, perhaps
including the accretion of matter condensing from an extended corona;
2) the "Local Group" theory, where they are part of the local warm-hot
intergalactic medium, representing some of the missing baryonic matter
of the Universe. Only direct distance determinations can discriminate
between these models. Our group has found that some of these highly
ionized HVCs have a Galactic origin, based on STIS observations of one
star at z5.3 kpc. We propose an HST FUV spectral survey to search for
and characterize the high velocity NV, CIV, and SiIV interstellar
absorption toward 24 stars at much larger distances than any previous
searches (4d21 kpc, 3|z|13 kpc). COS will provide atomic to highly
ionized species (e.g., OI, CII, CIV, SiIV) that can be observed at
sufficient resolution (R~22, 000) to not only detect these highly
ionized HVCs but also to model their properties and understand their
physics and origins. This survey is only possible because of the high
sensitivity of COS in the FUV spectral range.

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

Characterizing 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.

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.

WFC3/ACS/IR 11563

Galaxies at z~7-10 in the Reionization Epoch: Luminosity Functions to
0.2L* from Deep IR Imaging of the HUDF and HUDF05 Fields

The first generations of galaxies were assembled around redshifts
z~7-10+, just 500-800 Myr after recombination, in the heart of the
reionization of the universe. We know very little about galaxies in
this period. Despite great effort with HST and other telescopes, less
than ~15 galaxies have been reliably detected so far at z7,
contrasting with the ~1000 galaxies detected to date at z~6, just
200-400 Myr later, near the end of the reionization epoch. WFC3 IR can
dramatically change this situation, enabling derivation of the galaxy
luminosity function and its shape at z~7-8 to well below L*,
measurement of the UV luminosity density at z~7-8 and z~8-9, and
estimates of the contribution of galaxies to reionization at these
epochs, as well as characterization of their properties (sizes,
structure, colors). A quantitative leap in our understanding of early
galaxies, and the timescales of their buildup, requires a total sample
of ~100 galaxies at z~7-8 to ~29 AB mag. We can achieve this with 192
WFC3 IR orbits on three disjoint fields (minimizing cosmic variance):
the HUDF and the two nearby deep fields of the HUDF05. Our program
uses three WFC3 IR filters, and leverages over 600 orbits of existing
ACS data, to identify, with low contamination, a large sample of over
100 objects at z~7-8, a very useful sample of ~23 at z~8-9, and limits
at z~10. By careful placement of the WFC3 IR and parallel ACS
pointings, we also enhance the optical ACS imaging on the HUDF and a
HUDF05 field. We stress (1) the need to go deep, which is paramount to
define L*, the shape, and the slope alpha of the luminosity function
(LF) at these high redshifts; and (2) the far superior performance of
our strategy, compared with the use of strong lensing clusters, in
detecting significant samples of faint z~7-8 galaxies to derive their
luminosity function and UV ionizing flux. Our recent z~7.4 NICMOS
results show that wide-area IR surveys, even of GOODS-like depth,
simply do not reach faint enough at z~7-9 to meet the LF and UV flux
objectives. In the spirit of the HDF and the HUDF, we will waive any
proprietary period, and will also deliver the reduced data to STScI.
The proposed data will provide a Legacy resource of great value for a
wide range of archival science investigations of galaxies at redshifts
z~2-9. The data are likely to remain the deepest IR/optical images
until JWST is launched, and will provide sources for spectroscopic
followup by JWST, ALMA and EVLA.

WFC3/UVI/IR 11557

The Nature of Low-Ionization BAL QSOs

The rare subclass of optically-selected QSOs known as low-ionization
broad absorption line (LoBAL) QSOs show signs of high-velocity gas
outflows and reddened continua indicative of dust obscuration. Recent
studies show that galaxies hosting LoBAL QSOs tend to be ultraluminous
infrared systems that are undergoing mergers, and that have dominant
young ( 100 Myr) stellar populations. Such studies support the idea
that LoBAL QSOs represent a short- lived phase early in the life of
QSOs, when powerful AGN-driven winds are blowing away the dust and gas
surrounding the QSO. If so, understanding LoBALs would be critical in
the study of phenomena regulating black hole and galaxy evolution,
such as AGN feedback and the early stages of nuclear accretion. These
results, however, come from very small samples that may have serious
selection biases. We are therefore taking a more aggressive approach
by conducting a systematic multiwavelength study of a volume limited
sample of LoBAL QSOs at 0.5 z 0.6 drawn from SDSS. We propose to
image their host galaxies in two bands using WFC3/UVIS and WFC3/IR to
study the morphologies for signs of recent tidal interactions and to
map their interaction and star forming histories. We will thus
determine whether LoBAL QSOs are truly exclusively found in young
merging systems that are likely to be in the early stages of nuclear
accretion.

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/NUV/FUV 11522

COS-GTO: STAR FORMATION/LYMAN-ALPHA

A sample of 20 star-forming galaxies will be observed with COS G130M.
The galaxies were selected from the Kitt Peak International
Spectroscopic Survey (KISSR) data release and cover a broad range of
luminosity, oxygen abundance, and reddening. The goal of the program
is to characterize the Lyman-alpha properties and establish
correlations with fundamental galaxy properties. Each galaxy will be
observed for one orbit.

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/ACS/IR 11142

Revealing the Physical Nature of Infrared Luminous Galaxies at
0.3z2.7 Using HST and Spitzer

We aim to determine physical properties of IR luminous galaxies at
0.3z2.7 by requesting coordinated HST/NIC2 and MIPS 70um
observations of a unique, 24um flux-limited sample with complete
Spitzer mid-IR spectroscopy. The 150 sources investigated in this
program have S(24um) 0.8mJy and their mid-IR spectra have already
provided the majority targets with spectroscopic redshifts
(0.3z2.7). The proposed 150~orbits of NIC2 and 66~hours of MIPS 70um
will provide the physical measurements of the light distribution at
the rest-frame ~8000A and better estimates of the bolometric
luminosity. Combining these parameters together with the rich suite of
spectral diagnostics from the mid-IR spectra, we will (1) measure how
common mergers are among LIRGs and ULIRGs at 0.3z2.7, and establish
if major mergers are the drivers of z1 ULIRGs, as in the local
Universe, (2) study the co-evolution of star formation and blackhole
accretion by investigating the relations between the fraction of
starburst/AGN measured from mid-IR spectra vs. HST morphologies,
L(bol) and z, and (3) obtain the current best estimates of the far-IR
emission, thus L(bol) for this sample, and establish if the relative
contribution of mid-to-far IR dust emission is correlated with
morphology (resolved vs. unresolved).

FLIGHT OPERATIONS SUMMARY:

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

HSTARS:

12072 - GSAcq(2,1,1) results in fine lock backup (2,0,2) using FGS-2 @
318/21:25:56z

Observations possibly affected: WFC3 187 - 191 Proposal ID# 11548

12074 - GSAcq(1,2,1) fails during LOS due to scan step exceeded @
320/07:59z

Observations affected: ACS 5-8, Proposal ID# 11879; STIS 3, Proposal
ID# 10897; and COS 2 Proposal ID# 11895

COMPLETED OPS REQUEST:

18758-0 - NCS CPL from Standby to Pressure Prime @ 317/1558z

COMPLETED OPS NOTES: (None)

SCHEDULED SUCCESSFUL
FGS GSAcq 32 31
FGS REAcq 19 19
OBAD with Maneuver 15 15

SIGNIFICANT EVENTS: (None)