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Daily Rpt #4996



 
 
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Old December 22nd 09, 02:18 AM posted to sci.astro.hubble
Bassford, Lynn[_2_]
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Posts: 91
Default Daily Rpt #4996

HUBBLE SPACE TELESCOPE - Continuing to Collect World Class Science

DAILY REPORT #4996

PERIOD COVERED: 5am December 18 - 5am December 21, 2009 (DOY 352/10:00z-355/10:00z)

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 11914

UVIS Earth Flats

This program is an experimental path finder for Cycle 18 calibration.
Visible-wavelength flat fields will be obtained by observing the dark
side of the Earth during periods of full moon illumination. The
observations will consist of full-frame streaked WFC3 UVIS imagery:
per 22-min total exposure time in a single "dark-sky" orbit, we
anticipate collecting 7000 e/pix in F606W or 4500 e/pix in F814W. To
achieve Poisson S/N 100 per pixel, we require at least 2 orbits of
F606W and 3 orbits of F814W.

For UVIS narrowband filters, exposures of 1 sec typically do not
saturate on the sunlit Earth, so we will take sunlit Earth flats for
three of the more-commonly used narrowband filters in Cycle 17 plus
the also-popular long-wavelength quad filters, for which we get four
filters at once.

Why not use the Sunlit Earth for the wideband visible-light filters?
It is too bright in the visible for WFC3 UVIS minimum exposure time of
0.5 sec. Similarly, for NICMOS the sunlit-Earth is too bright which
saturates the detector too quickly and/or induces abnormal behaviors
such as super-shading (Gilmore 1998, NIC 098-011). In the narrowband
visible and broadband near-UV its not too bright (predictions in Cox
et al. 1987 "Standard Astronomical Sources for HST: 6. Spatially Flat
Fields." and observations in ACS Program 10050).

Other possibilities? Cox et al.'s Section II.D addresses many other
possible sources for flat fields, rejecting them for a variety of
reasons. A remaining possibility would be the totally eclipsed moon.
Such eclipses provide approximately 2 hours (1 HST orbit) of
opportunity per year, so they are too rare to be generically useful.
An advantage of the moon over the Earth is that the moon subtends less
than 0.25 square degree, whereas the Earth subtends a steradian or
more, so scattered light and light potentially leaking around the
shutter presents additional problems for the Earth. Also, we're unsure
if HST can point 180 deg from the Sun.

WFC3/UVIS 11912

UVIS Internal Flats

This proposal will be used to assess the stability of the flat field
structure for the UVIS detector throughout the 15 months of Cycle 17.
The data will be used to generate on- orbit updates for the delta-flat
field reference files used in the WFC3 calibration pipeline, if
significant changes in the flat structure are seen.

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).

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.

FGS 11872

Monitoring FGS1R's Interferometric Response as a Function of Spectral
Color

This proposal uses FGS1R in Transfer mode to observe four stars with
B-V values 0.2, 0.6, 1.4, and 2.0, to form the basis of the FGS point
source library of interference fringes as a function of a star's
spectral color. This library will be used to analyze binary star
science observations, and to monitor any long-term changes in the
FGS1R S-curves. In addition, this proposal uses FGS1R in Position mode
to observe the B-V = 0.2 and 2.0 stars and several nearby reference
stars, all of which "fit" in the FGS1R pickle at the selected HST
orients in visits 01 and 02. These Visits are to execute when the
target field is in the anti-Sun direction (Dec 20-23, 2009). The
orient of visit 01 differs from that of visit 02 by ~195 degrees so
that the "lateral color" induced shift of the star's centroid can be
determined as a function of B-V. Visit 03 (Upgren69) is to execute
before SM4. Visit 04 (HD233877) is to execute Feb-April 2010 as a
stability monitor.

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/ACS/UVIS 11803

Observing Cluster Assembly Around the Massive Cluster RXJ0152-13

We request ACS imaging for groups and filaments in the outskirts of
two z=0.8 forming clusters of galaxies. These images will be combined
with an unparalleled dataset of wide-field spectroscopy from Magellan,
with ~2200 confirmed members (~3200 by the summer) of the
superstructures surrounding the two clusters. We will estimate merger
rates and determine the morphological composition of the galaxy
populations within the infalling groups and filaments identified in
our spectroscopic dataset. The HST data are critical to understand how
the early-type galaxy fraction remains constant in cluster centers,
while clusters double in mass through the steady accretion of lower
mass groups. One possibility is that the galaxies in the filaments and
infalling groups already have predominantly early-type morphologies,
while another is that galaxies transform during, and possibly even in
connection with, the process of infall. Our unique dataset of
spectroscopic membership, when combined with the exquisite
high-resolution imaging of ACS and WF3, will enable us to witness the
accretion of galaxies unto massive clusters and how this process
affects their properties.

COS/NUV/FUV 11727

UV Spectroscopy of Local Lyman Break Galaxy Analogs: New Clues to
Galaxy Formation in the Early Universe

Much of our information about galaxy evolution and the interaction
between galaxies and the IGM at high-z has been provided by the Lyman
Break Galaxies (LBGs). However, it is difficult to investigate these
faint and distant objects in detail. To address this, we have used the
GALEX All-Sky Imaging Survey and the SDSS to identify for the first
time a rare population of low-redshift galaxies with properties
remarkably similar to the high-redshift LBGs. These local "Lyman Break
Analogs" (LBAs) resemble LBGs in terms of morphology, size, UV
luminosity, star formation rate, UV surface brightness, stellar mass,
velocity dispersion, metallicity, and dust content. We are assembling
a wide range of data on these objects with the goal of using them as
local laboratories for better understanding the relevant astrophysical
processes in LBGs. These data include HST imaging (95 orbits in Cy15
and 16), Spitzer photometry and spectroscopy, Chandra and XMM X-ray
imaging and spectroscopy, and near-IR integral field spectroscopy
(VLT, Keck, and Gemini). In this proposal we are requesting the most
important missing puzzle piece: far-UV spectra with a signal-to-noise
and spectral resolution significantly better than available for
typical LBGs. We will use these spectra to study the LBA's galactic
winds, probe the processes that regulate the escape of Ly-a and Lyman
continuum radiation, determine chemical abundances for the stars and
gas, and constrain the form of the high-end of the Initial Mass
Function. Adding these new COS data will give us vital information
about these extraordinary sites of star formation in the local
universe. In so-doing it will also shed new light on the processes
that led to the formation of stars, the building of galaxies, and the
enrichment and heating of the IGM in the early universe.

COS/NUV/FUV 11720

Detailed Analysis of Carbon Atmosphere White Dwarfs

We propose to obtain UV spectra for the newly discovered white dwarf
stars with a carbon-dominated atmosphere. Model calculations show that
these stars emit most of their light in the UV part of the
electromagnetic spectrum and that an accurate determination of the
flux in this region is crucial for an accurate determination of the
atmospheric parameters. It will also provide a unique opportunity to
test the atomic data and broadening theory in stellar conditions never
met before. This will play a primordial role in our path to understand
the origin of these objects as well to obtain a better understanding
of the evolution of stars in general. The principal objective we hope
to achieve with these observations are 1) obtain accurate surface
gravity/mass for these stars, 2) constrain/determine the abundance of
other elements (O, He, Mg, Ne etc.), especially oxygen, 3) verify the
accuracy of the various theoretical atomic data used in the model
calculations, 4) understand the origin and evolution of carbon
atmosphere white dwarfs, in particular whether progenitor stars as
massive as 10.5 solar masses can produce white dwarfs, rather than
supernovae. We propose to observe 5 objects chosen carefully to cover
the range of observed properties among carbon atmosphere white dwarfs
(effective temperature, surface gravity, abundance of hydrogen/helium
and magnetic field).

WFC3/IR 11712

Calibration of Surface Brightness Fluctuations for WFC3/IR

We aim to characterize galaxy surface brightness fluctuations (SBF),
and calibrate the SBF distance method, in the F110W and F160W filters
of the Wide Field Camera 3 IR channel. Because of the very high
throughput of F110W and the good match of F160W to the standard H
band, we anticipate that both of these filters will be popular choices
for galaxy observations with WFC3/IR. The SBF signal is typically an
order of magnitude brighter in the near-IR than in the optical, and
the characteristics (sensitivity, FOV, cosmetics) of the WFC3/IR
channel will be enormously more efficient for SBF measurements than
previously available near-IR cameras. As a result, our proposed SBF
calibration will allow accurate distance derivation whenever an
early-type or bulge- dominated galaxy is observed out to a distance of
150 Mpc or more (i.e., out to the Hubble flow) in the calibrated
passbands. For individual galaxy observations, an accurate distance is
useful for establishing absolute luminosities, black hole masses,
linear sizes, etc. Eventually, once a large number of galaxies have
been observed across the sky with WFC3/IR, this SBF calibration will
enable accurate mapping of the total mass density distribution in the
local universe using the data available in the HST archive. The
proposed observations will have additional important scientific value;
in particular, we highlight their usefulness for understanding the
nature of multimodal globular cluster color distributions in giant
elliptical galaxies.

WFC3/UVIS/IR 11700

Bright Galaxies at z7.5 with a WFC3 Pure Parallel Survey

The epoch of reionization represents a special moment in the history
of the Universe as it is during this era that the first galaxies and
star clusters are formed. Reionization also profoundly affects the
environment where subsequent generations of galaxies evolve. Our
overarching goal is to test the hypothesis that galaxies are
responsible for reionizing neutral hydrogen. To do so we propose to
carry out a pure parallel WFC3 survey to constrain the bright end of
the redshift z7.5 galaxy luminosity function on a total area of 176
arcmin^2 of sky. Extrapolating the evolution of the luminosity
function from z~6, we expect to detect about 20 Lyman Break Galaxies
brighter than M_* at z~8 significantly improving the current sample of
only a few galaxies known at these redshifts. Finding significantly
fewer objects than predicted on the basis of extrapolation from z=6
would set strong limits to the brightness of M_*, highlighting a fast
evolution of the luminosity function with the possible implication
that galaxies alone cannot reionize the Universe. Our observations
will find the best candidates for spectroscopic confirmation, that is
bright z7.5 objects, which would be missed by small area deeper
surveys. The random pointing nature of the program is ideal to beat
cosmic variance, especially severe for luminous massive galaxies,
which are strongly clustered. In fact our survey geometry of 38
independent fields will constrain the luminosity function like a
contiguous single field survey with two times more area at the same
depth. Lyman Break Galaxies at z7.5 down to m_AB=26.85 (5 sigma) in
F125W will be selected as F098M dropouts, using three to five orbits
visits that include a total of four filters (F606W, F098M, F125W,
F160W) optimized to remove low-redshift interlopers and cool stars.
Our data will be highly complementary to a deep field search for
high-z galaxies aimed at probing the faint end of the luminosity
function, allowing us to disentangle the degeneracy between faint end
slope and M_* in a Schechter function fit of the luminosity function.
We waive proprietary rights for the data. In addition, we commit to
release the coordinates and properties of our z7.5 candidates within
one month from the acquisition of each field.

WFC3/IR 11696

Infrared Survey of Star Formation Across Cosmic Time

We propose to use the unique power of WFC3 slitless spectroscopy to
measure the evolution of cosmic star formation from the end of the
reionization epoch at z6 to the close of the galaxy-building era at
z~0.3.Pure parallel observations with the grisms have proven to be
efficient for identifying line emission from galaxies across a broad
range of redshifts. The G102 grism on WFC3 was designed to extend this
capability to search for Ly-alpha emission from the first galaxies.
Using up to 250 orbits of pure parallel WFC3 spectroscopy, we will
observe about 40 deep (4-5 orbit) fields with the combination of G102
and G141, and about 20 shallow (2-3 orbit) fields with G141 alone.

Our primary science goals at the highest redshifts a (1) Detect Lya
in ~100 galaxies with z5.6 and measure the evolution of the Lya
luminosity function, independent of of cosmic variance; 2) Determine
the connection between emission line selected and continuum-break
selected galaxies at these high redshifts, and 3) Search for the
proposed signature of neutral hydrogen absorption at re-ionization. At
intermediate redshifts we will (4) Detect more than 1000 galaxies in
Halpha at 0.5z1.8 to measure the evolution of the
extinction-corrected star formation density across the peak epoch of
star formation. This is over an order-of-magnitude improvement in the
current statistics, from the NICMOS Parallel grism survey. (5) Trace
``cosmic downsizing" from 0.5z2.2; and (6) Estimate the evolution in
reddening and metallicty in star-forming galaxies and measure the
evolution of the Seyfert population. For hundreds of spectra we will
be able to measure one or even two line pair ratios -- in particular,
the Balmer decrement and [OII]/[OIII] are sensitive to gas reddening
and metallicity. As a bonus, the G102 grism offers the possibility of
detecting Lya emission at z=7-8.8.

To identify single-line Lya emitters, we will exploit the wide
0.8--1.9um wavelength coverage of the combined G102+G141 spectra. All
[OII] and [OIII] interlopers detected in G102 will be reliably
separated from true LAEs by the detection of at least one strong line
in the G141 spectrum, without the need for any ancillary data. We
waive all proprietary rights to our data and will make high-level data
products available through the ST/ECF.

COS/NUV/FUV/STIS/CCD/MA1 11692

The LMC as a QSO Absorption Line System

We propose to obtain high resolution, high signal-to-noise
observations of QSOs behind the Large Magellanic Clouds. These QSOs
are situated beyond the star forming disk of the galaxy, giving us the
opportunity to study the distribution of metals and energy in regions
lacking significant star formation. In particular, we will derive the
metallicities and study the ionization characteristics of LMC gas at
impact parameters 3-17 kpc. We will compare our results with high-z
QSO absorption line systems.

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.

STIS/CCD 11596

Coronagraphic Imaging of Debris Disks Containing Gas

We recently found a new sample of edge-on debris disks using the
Spitzer Space Telescope. These disks are particularly valuable because
they have observable circumstellar gas as well as dust. They double
the small number of debris disks that can be used to study gas-dust
interactions in optically-thin disks, as well as the evolution of
circumstellar gas during the terrestrial planet-forming phase. We
propose HST-STIS coronagraphic imaging of the two closest disks from
our sample, in order to image light scattered from the dust disks in a
broad optical bandpass. These observations will provide a wealth of
information about the disks, including their sizes, radial surface
brightness profiles, and basic morphologies (ring-like or smooth
disk). They may also reveal dust structures (e.g. clumps) that are
often seen in optical images of debris disks and may be generated by
the influence of unseen planets. This proposed program is a crucial
step towards full characterization of the circumstellar material in
two important debris disks.

COS/FUV/STIS/CCD/MA1 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/UVIS 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.

WFC3/UVIS 11588

Galaxy-Scale Strong Lenses from the CFHTLS Survey

We aim to investigate the origin and evolution of early-type galaxies
using gravitational lensing, modeling the mass profiles of objects
over a wide range of redshifts. The low redshift (z = 0.2) sample is
already in place following the successful HST SLACS survey; we now
propose to build up and analyze a sample of comparable size (~50
systems) at high redshift (0.4 z 0.9) using HST WFC3 Snapshot
observations of lens systems identified by the SL2S collaboration in
the CFHT legacy survey.

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 methods 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/ACS/UVIS/IR 11570

Narrowing in on the Hubble Constant and Dark Energy

A measurement of the Hubble constant to a precision of a few percent
would be a powerful aid to the investigation of the nature of dark
energy and a potent "end-to end" test of the present cosmological
model. In Cycle 15 we constructed a new streamlined distance ladder
utilizing high-quality type Ia supernova data and observations of
Cepheids with HST in the near-IR to minimize the dominant sources of
systematic uncertainty in past measurements of the Hubble constant and
reduce its total uncertainty to a little under 5%. Here we propose to
exploit this new route to reduce the remaining uncertainty by more
than 30%, translating into an equal reduction in the uncertainty of
the equation of state of dark energy. We propose three sets of
observations to reach this goal: a mosaic of NGC 4258 with WFC3 in
F160W to triple its sample of long period Cepheids, WFC3/F160W
observations of the 6 ideal SN Ia hosts to triple their samples of
Cepheids, and observations of NGC 5584 the host of a new SN Ia, SN
2007af, to discover and measure its Cepheids and begin expanding the
small set of SN Ia luminosity calibrations. These observations would
provide the bulk of a coordinated program aimed at making the
measurement of the Hubble constant one of the leading constraints on
dark energy.

COS/FUV 11541

COS-GTO: Cool, Warm, and Hot Gas in the Cosmic Web and in Galaxy Halos

COS G130M and G160M 20, 000 resolution observations will be obtained
for 17 QSOs to study cool, warm and hot gas in the cosmic web and in
galaxy halos. 5 QSOs with z from 0.177 to 0.574 and sum z = 1.68 will
be observed with S/N = 40-50 per resolution element. 12 QSOs with z =
0.286 to 0.669 and sum z = 5.57 will be observed with S/N = 30-40. The
observations will allow a wide range of IGM studies including
determining the frequency of occurrence of the different types of
absorption systems detected, along with studies of the physical
conditions and elemental abundances in the different systems. Special
emphasis will be given to a study of the properties of highly ionized
IGM as traced by O VI, O V, O IV, N V, and C IV. The high S/N of the
observations will allow a search for broad Lyman alpha absorption and
weak metal line absorption that can be crucial for the evaluation of
physical conditions and elemental abundances. Supporting ground based
observations will allow studies of the association of the absorbers
with galaxy structures along the 17 lines of sight. The overall goal
of the program will be to obtain the information that will allow an
assessment of the baryonic content of the IGM as revealed by UV and
EUV absorption lines seen in the spectra of QSOs.

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).

NIC3/WFC3/IR 11153

The Physical Nature and Age of Lyman Alpha Galaxies

In the simplest scenario, strong Lyman alpha emission from high
redshift galaxies would indicate that stellar populations younger than
10 Myrs dominate the UV. This does not, however, constrain the stellar
populations older than 100 Myrs, which do not contribute to UV light.
Also, the Lyman alpha line can be boosted if the interstellar medium
is both clumpy and dusty. Different studies with small samples have
reached different conclusions about the presence of dust and old
stellar populations in Lyman alpha emitters. We propose HST-NICMOS and
Spitzer-IRAC photometry of 35 Lyman-alpha galaxies at redshift
4.5z6.5, in order to determine their spectral energy distribution
(SED) extending through rest-frame optical. This will allow us to
measure accurately (1) The total stellar mass in these objects,
including old stars which may have formed at redshifts (z 8) not
easily probed by any other means. (2) The dust extinction in the rest-
frame UV, and therefore a correction to their present star-formation
rates. Taken together, these two quantities will yield the
star-formation histories of Lyman alpha galaxies, which form fully
half of the known galaxies at z=4-6. They will tell us whether these
are young or old galaxies by straddling the 4000A break. Data from
NICMOS is essential for these compact and faint (i=25-26th magnitude
AB) high redshift galaxies, which are too faint for good near-IR
photometry from the ground.

NIC2/WFC3/IR 11143

NICMOS Imaging of Submillimeter Galaxies with CO and PAH Redshifts

We propose to obtain F110W and F160W imaging of 10 z~2.4 submillimeter
galaxies (SMGs) whose optical redshifts have been confirmed by the
detection of millimeter CO and/or mid-infrared PAH emission. With the
4000A break falling within/between the two imaging filters, we will be
able to study these sources' spatially resolved stellar populations
(modulo extinction) in the rest-frame optical. SMGs' large
luminosities appear to be due largely to merger-triggered starbursts;
high-resolution NICMOS imaging will help us understand the stellar
masses, mass ratios, and other properties of the merger progenitors,
valuable information in the effort to model the mass assembly history
of the universe.

ACS/WFC3 11138

The Physics of the Jets of Powerful Radio Galaxies and Quasars

We propose to obtain HST polarimetry of the jets of the quasars
1150+497 and PKS 1136-135. Our goal is to solve the riddle of their
high-energy emission mechanism, and tackle issues such as particle
acceleration and jet dynamics. Our targets are the optically brightest
quasar jets, and they span the range of luminosities and beaming
parameters seen in these objects. Recent observations with Spitzer,
HST and Chandra have shed new light on the spectral morphology of
quasar jets, throwing wide open the question of the nature of their
optical and X-ray emission. Three mechanisms are possible, including
synchrotron emission as well as two Comptonization processes.
Polarimetry can uniquely determine which of these mechanisms operates
in the optical. We will compare the optical polarimetry to in-hand
radio polarimetry as well as in-hand and new Spitzer, HST and Chandra
imaging to gain new insights on the structure of these jets, as well
as particle acceleration mechanisms and jet dynamics.

FLIGHT OPERATIONS SUMMARY:

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

HSTARS:

#12138 GSAcq(1,2,1) @352/22:59:07z and REAcq(1,2,1) @353/00:33:15z,
353/02:09:07z & 353/03:45:01z failed to gyro control due to search
radius limit exceeded on FGS-1

Observations affected: STIS #31-37 Proposal #11572; WFC3 #159-161
Proposal #11905

COMPLETED OPS REQUEST:

#18783-0 CONTINGENCY: Continuous FGS Loss of Lock Looping - updated
(Generic) 352/23:18z

COMPLETED OPS NOTES: (None)

SCHEDULED SUCCESSFUL
FGS GSAcq 27 26
FGS REAcq 15 12
OBAD with Maneuver 20 20

SIGNIFICANT EVENTS:

Final Gyro 3 Reconfiguration to Backup Heater Flash Report:

The Gyro 3 heater controller was switched to the backup controller at
350/21:45. Initial biases measurements up to 351/01:50 were nominal,
however the GS acquisition at 351/02:57 failed to Loss of Lock (LOL)
looping which was indicative of a bias issue. Subsequent biases
appeared to increase in the V2 and V3 axes and acquisitions between
06:07 and 10:27 failed due to search radius limit exceeds (SRLEX) or
LOL looping while efforts were made to correct the bias. The GS
acquisition at 12:01 was successful and performed an onboard bias
update. The GS acquisition at 13:05 failed due to a dim star. The full
GS acquisition at 19:01 was successful and subsequent successful
acquisitions confirm that the EOD transition signature has been
reduced back to a typical nominal gyro observer bias signature and
that the bias has stabilized. The transients across the EOD crossings
are less than 10 arcsec/hr and the bias subsequently returns to its
pre-EOD trend after the EOD crossing.
 




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