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Daily Report #5135



 
 
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Old July 12th 10, 04:58 PM posted to sci.astro.hubble
Cooper, Joe
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Default Daily Report #5135

HUBBLE SPACE TELESCOPE - Continuing to Collect World Class Science

DAILY REPORT #5135

PERIOD COVERED: 5am July 9 - 5am July 12, 2010 (DOY 190/09:00z-193/09:00z)

FLIGHT OPERATIONS SUMMARY:

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

HSTARS:

12325 - GSAcq(2,1,1) at 190/17:54:12z resulted in Fine lock Backup on
FGS2. The subsequent REAcqs at 190/19:29:27z and 190/21:05:20z also
resulted in fine lock backup on FGS2.

Observations possibly affected COS 98-109 Proposal ID# 11598; WFC3 135
Proposal ID# 11908

12326 - GSAcq(1,2,1) at 191/01:33:56z resulted in fine lock backup on
FGS2 after scan step limit exceeded on FGS2. The subsequent REAcq at
191/02:52:29z also resulted in fine lock backup on FGS2.

Observations possibly affected: STIS 36, 37 Proposal ID# 11845; STIS
38-40 Proposal ID# 11847; WFC3 140-142 Proposal ID# 11661

COMPLETED OPS REQUEST:

18871-0 - Execute ROP NS-12 to Reset STIS FSW Error Count @ 190/1450z
17543-3 - Dump OBAD Tables After Failed OBAD @ 191/2048z, 191/2049z
18870-1 - Eclipse Management for 192/18:26 Eclipse (July 11) @ 192/2141z

COMPLETED OPS NOTES: (None)

SCHEDULED SUCCESSFUL
FGS GSAcq 20 20
FGS REAcq 23 23
OBAD with Maneuver 16 16

SIGNIFICANT EVENTS:

Lunar Solar Eclipse 2010/192

OPS Request 18870 was successfully executed to configure the FSW
processing of CSS data and temporarily disable Rate of Charge (ROC)
safemode test during the moon shadow that occurred from 192/18:16z to
18:54z.

During the eclipse period, the minimum FSW SOC was approximately 438
A-hr, the maximum 482 A-hr and the FSW Benchmark was not reset.
However, the batteries were charged nominally on the following orbit
and benchmark reset was achieved.


OBSERVATIONS SCHEDULED:

S/C 12046

COS FUV DCE Memory Dump

Whenever the FUV detector high voltage is on, count rate and current
draw information is collected, monitored, and saved to DCE memory.
Every 10 msec the detector samples the currents from the HV power
supplies (HVIA, HVIB) and the AUX power supply (AUXI). The last 1000
samples are saved in memory, along with a histogram of the number of
occurrences of each current value.

In the case of a HV transient (known as a "crackle" on FUSE), where
one of these currents exceeds a preset threshold for a persistence
time, the HV will shut down, and the DCE memory will be dumped and
examined as part of the recovery procedure. However, if the current
exceeds the threshold for less than the persistence time (a
"mini-crackle" in FUSE parlance), there is no way to know without
dumping DCE memory. By dumping and examining the histograms regularly,
we will be able to monitor any changes in the rate of "mini-crackles"
and thus learn something about the state of the detector.

ACS/WFC 11996

CCD Daily Monitor (Part 3)

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 308 orbits (19.25 weeks) from 21 June
2010 to 1 November 2010.

WFC3/IR 11931

IR Signal Non-Linearity Calibration

These observations will be used to quantify the non-linear signal
behavior of the IR channel, as well as to create the IR channel
non-linearity calibration reference file. The non-linearity behavior
of each pixel in the detector will be investigated through the use of
flat fields, while the photometric behavior of point sources will be
studied using observations of 47 Tuc.

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/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/UV 11918

WFC3 UVIS Image Quality

The UVIS imaging performance over the detector will be assessed
periodically (every 4 months) in two passbands (F275W and F621M) to
check for image stability. The field around star 58 in the open
cluster NGC188 is the chosen target because it is sufficiently dense
to provide good sampling over the FOV while providing enough isolated
stars to permit accurate PSF (point spread function) measurement. It
is available year-round and used previously for ACS image quality
assessment. The field is astrometric, and astrometric guide stars will
be used, so that the plate scale and image orientation may also be
determined if necessary (as in SMOV proposals 11436 and 11442). Full
frame images will be obtained at each of 4 POSTARG offset positions
designed to improve sampling over the detector.

This proposal is a periodic repeat (once every 4 months) of visits
similar to those in SMOV proposal 11436 (activity ID WFC3-23). The
data will be analyzed using the code and techniques described in ISR
WFC3 2008-40 (Hartig). Profiles of encircled energy will be monitored
and presented in an ISR. If an update to the SIAF is needed, (V2, V3)
locations of stars will be obtained from the Flight Ops Sensors and
Calibrations group at GSFC, the (V2, V3) of the reference pixel and
the orientation of the detector will be determined by the WFC3 group,
and the Telescopes group will update and deliver the SIAF to the PRDB
branch.

The specific PSF metrics to be examined are encircled energy for
aperture diameter 0.15, 0.20, 0.25, and 0.35 arcsec, FWHM, and
sharpness. (See ISR WFC3 2008-40 tables 2 and 3 and preceding text.)
about 20 stars distributed over the detector will be measured in each
exposure for each filter. The mean, rms, and rms of the mean will be
determined for each metric. The values determined from each of the 4
exposures per filter within a visit will be compared to each other to
see to what extent they are affected by "breathing". Values will be
compared from visit to visit, starting with the values obtained during
SMOV after the fine alignment has been performed, to see if the
measures of the compactness of the PSF indicate degradation over time.
The analysis will be repeated for stars on the inner part of the
detector and stars on the outer part of the detector to check for
differential degradation of the PSF.

As an example of the analysis, one can examine the sharpness of the
F275W PSF exposures made during thermal vacuum testing (ISR WFC3
2008-40). To compare two samples, one can define the PSFs on each CCD
chip as a sample of 8. The mean, rms, and rms of the mean sharpness
are 0.0676, 0.0093, and 0.0035 for one chip, and 0.0701, 0.0085, and
0.0032 for the other. The difference of the means is 0.0025 and the
statistical error in that difference is 0.0048, so the difference is
not significant.

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 11882

CCD Hot Pixel Annealing

This program continues the monthly anneal that has taken place every
four weeks for the last three cycles. We now obtain WFC biases and
darks before and after the anneal in the same sequence as is done for
the ACS daily monitor (now done 4 times per week). So the anneal
observation supplements the monitor observation sets during the
appropriate week. Extended Pixel Edge Response (EPER) and First Pixel
Response (FPR) data will be obtained over a range of signal levels for
the Wide Field Channel (WFC). 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. The High
Resolution Channel (HRC) visits have been removed since it could not
be repaired during SM4.

This program also assesses the read noise, bias structure, and
amplifier cross-talk of ACS/WFC using the GAIN=1.4 A/D conversion
setting. This investigation serves as a precursor to a more
comprehensive study of WFC performance using GAIN=1.4.

STIS/CC 11847

CCD Bias Monitor-Part 2

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/CC 11845

CCD Dark Monitor Part 2

Monitor the darks for the STIS CCD.

ACS/WFC 11831

Probing X-Ray Jet Emission Mechanisms in a Complete Blazar Sample

We propose deep (70 ksec) followup Chandra X-ray observations and new
HST ACS/WFC/F475W observations of two quasars, viz., 0106+013 and
1641+399, belonging to the complete flux-limited MOJAVE Chandra blazar
sample. These two quasars have HST WFPC2/F702W data available in the
archive. Combining the existing optical and radio data with the new
Chandra and HST data at an additional optical band we aim to construct
a significantly more accurate multi-waveband (four frequency) spectral
energy distributions for distinct knots in the jets. This will serve
as a first step towards resolving longstanding ambiguities surrounding
the primary X-ray emission mechanisms in a well-defined sample of
powerful FR-II class jets.

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.

WFC3/UVIS 11697

Proper Motion Survey of Classical and SDSS Local Group Dwarf Galaxies

Using the superior resolution of HST, we propose to continue our
proper motion survey of Galactic dwarf galaxies. The target galaxies
include one classical dwarf, Leo II, and six that were recently
identified in the Sloan Digital Sky Survey data: Bootes I, Canes
Venatici I, Canes Venatici II, Coma Berenices, Leo IV, and Ursa Major
II. We will observe a total of 16 fields, each centered on a
spectroscopically-confirmed QSO. Using QSOs as standards of rest in
measuring absolute proper motions has proven to be the most accurate
and most efficient method. HST is our only option to quickly determine
the space motions of the SDSS dwarfs because suitable ground-based
imaging is only a few years old and such data need several decades to
produce a proper motion. The two most distant galaxies in our sample
will require time baselines of four years to achieve our goal of a
30-50 km/s uncertainty in the tangential velocity; given this and the
finite lifetime of HST, it is imperative that first-epoch observations
be taken in this cycle. The SDSS dwarfs have dramatically lower
surface brightnesses and luminosities than the classical dwarfs.
Proper motions are crucial for determining orbits of the galaxies and
knowing the orbits will allow us to test theories for the formation
and evolution of these galaxies and, more generally, for the formation
of the Local Group.

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.

WFC3/ACS/UVIS 11684

The First Proper Motion Measurement for M31: Dynamics and Mass of the
Local Group

We will perform observations to determine the proper motion of the
Andromeda galaxy M31, which has been sought for almost a century
without success. While challenging, this measurement has now become
possible due to the availability of existing deep ACS/WFC images of
several M31 fields. The requested second epoch images will yield the
average shift of the M31 stars with respect to compact galaxies in the
background. Our observing strategy uses six different fields (three
primary and three coordinated parallel) with two different instruments
(ACS and WFC3) to provide a maximum handle on possible systematic
effects. The expected result will be sufficiently accurate to: (a)
discriminate between different histories for the dynamics of the Local
Group; (b) constrain the mass distribution of the Local Group; (c)
determine the details of the expected future merger between M31 and
the Milky Way; (d) infer the past interaction history between M31 and
M33; (e) constrain the internal proper motion kinematics of the M31
spheroid, outer disk, and tidal stream; and (f) obtain a pilot
estimate of the M31 distance through the method of rotational
parallax.

WFC3/UVI 11680

The Main Sequence Luminosity Function of Low-Mass Globular Clusters

Theoretical work indicates that the dynamical evolution of globular
clusters of low mass and low central concentration is strongly
determined by mass-loss processes, such as stellar evaporation and
tidal stripping, that can eventually lead to cluster dissolution. In
fact, mass loss and cluster disruption is now considered to be a
viable explanation for the form of the faint end of the Milky Way
globular cluster luminosity function. A clear observational
demonstration of the prevalence of cluster mass-loss would have
ramifications not only for the dynamical evolution of individual
globular clusters and their internal stellar mass distributions, but
also for the relationships between halo field and cluster stars and
the properties of globular cluster systems in galaxies. Our previous
WFPC2 imaging of the low-mass diffuse halo cluster Palomar 5 revealed
a main sequence deficient in stars compared to other low-concentration
globular clusters of much higher mass, consistent with there having
been a considerable loss of stars from this system. But is Pal 5
typical of low-mass, low-concentration halo clusters? We propose to
place the mass-loss scenario on a firm observational footing (or
otherwise) by using WFC3 imaging to measure the main-sequence stellar
mass functions of two of the lowest-mass lowest-concentration globular
clusters in the Milky Way, AM-4 and Palomar 13, in order to search for
analogous evidence of stellar depletion.

WFC3/UVIS 11661

The Black Hole Mass - Bulge Luminosity Relationship for the Nearest
Reverberation-Mapped AGNs

We propose to obtain WFC3 host galaxy images of the eight nearest AGNs
with masses from reverberation mapping, and one star as a PSF model.
These images will allow us to determine with unprecedented accuracy
the bulge luminosities of the host galaxies, a goal which is not
achievable from the ground due to the blurring of the very bright PSF
component under typical, and even very good, seeing conditions.
High-resolution ACS images of the host galaxies of more luminous AGNs
reveal that the black hole mass-bulge luminosity and black hole
mass-bulge mass relationships for AGNs are not well constrained and
arise from what appear to be fundamentally flawed data sets. With the
addition of the images proposed here to our current sample of ACS
images, we will be able to extend our determinations of the black hole
mass- bulge luminosity and black hole mass-bulge mass relationships
for AGNs by an order of magnitude and test our preliminary results for
these fundamentally important relationships against those previously
determined for quiescent galaxies.

COS/NUV/ACS/WFC/FUV 11658

Probing the Outer Regions of M31 with QSO Absorption Lines

We propose HST-COS spectroscopy of 10 quasars behind M31. Absorption
lines due to MgII, FeII, CIV, and a variety of other lines will be
searched for and measured. Six quasars lie between 1 and 4.2 Holmberg
radii near the major axis on the southwest side, where confusion with
Milky Way gas is minimized. Two lie even farther out on the southwest
side of the major axis. One lies within 1 Holmberg radius. Two of the
10 pass through M31's high velocity clouds seen in a detailed 21 cm
emission map. Exposure time estimates were based on SDSS magnitudes
and available GALEX magnitudes. Thus, using the most well-studied
external spiral galaxy in the sky, our observations will permit us to
check, better than ever before, the standard picture that quasar
metal-line absorption systems such as MgII and CIV arise in an
extended gaseous halo/disk of a galaxy well beyond its observable
optical radius. The observations will yield insights into the nature
of the gas and its connection to the very extended stellar components
of M31 that have recently been studied. Notably the observations have
the potential of extending M31's rotation curve to very large
galactocentric distances, thereby placing new constrants on M31's dark
matter halo.

Finally, we also request that the coordinated parallel orbits be
allocated to this program so that we may image the resolved stellar
content of M31's halo and outer disk.

WFC3/IR 11648

WFC3 Spectroscopy of an X-ray Luminous Galaxy Cluster at z2

We propose to obtain deep WFC3+G141 grism observations to
spectroscopically confirm a remarkable z2 cluster of galaxy
candidate. Over a 1000 arcmin^2 field imaged with Spitzer's IRAC we
have discovered a compact (30ÕÕ diameter) concentration of extremely
red galaxies with a factor of 40 overdensity over the adjacent field.
Among these galaxies for which we can derive meaningful photometric
redshifts, 17 are consistent with zphot=2-2.5, making it very likely
that the concentration is a real cluster at such high redshift. This
is further supported by a 3.5 sigma detection of extended X-Ray
emission on XMM-Newton data, by a likely color magnitude sequence of
red galaxies, and by the presence of a giant galaxy consistent with a
BCG at the cluster redshift. The general faintness of the red galaxies
in all optical bands and their high redshifts prevent confirmation of
this cluster with ordinary optical spectroscopy. The WFC3 camera with
G141 grism provides the only way to confirm this record high-z cluster
and measure its redshift from spectral breaks typical of old stellar
populations. Our deep integrations will reveal redshifts for at least
19 ultra-red galaxies in the area and of a similar number of bluer
galaxies at the cluster redshift. Knowledge of the cluster redshift
based on the HST spectra will allow us to reach important scientific
aims: find the most distant Xray emitting evolved galaxy cluster,
determine membership of the other galaxies from photometric SED
analysis, study their stellar population properties, characterize the
color-magnitude relation with constraints on the formation redshift.
The proposed observations will establish a first z2 benchmark for
cluster field comparisons of galaxy formation at this highest redshift
and will firmly establish the progenitors of local rich Abell
clusters.

STIS/CC 11626

Searching for the Upper Mass Limit in NGC 3603, the Nearest Giant H II
Region

What is the mass of the highest mass star? 100Mo? 150Mo? 200Mo? Or
higher? Theory gives us little guidance as to what physics sets the
upper mass limit, presuming one exists. Is it due to limitations in
the highest masses that can coalesce? Or is it due to stability issues
in such a behemoth? Observationally, the upper mass limit is poorly
constrained at present, with the strongest evidence coming from the
K-band luminosity function of the Arches cluster near the Galactic
Center. Here we propose to investigate this question by determining
the Initial Mass Function of NGC 3603, the nearest giant H II region.
This cluster is known to contain a wealth of O3 and hydrogen-rich
Wolf-Rayets, the most luminous and massive of stars. By constructing
an accurate H-R diagram for the cluster, we will construct a present
day mass function using newly computed high mass evolutionary tracks,
and convert this to an initial mass function using the inferred ages.
This will allow us to see whether or not there is a true deficit of
high mass stars, evidence of an upper mass cutoff. At the same time we
are likely to establish good masses for the highest mass stars ever
determined. We have laid the groundwork for this project using the
Magellan 6.5-m telescope and the excellent seeing found on Las
Campanas, plus analysis of archival ACS/HRS frames, but we now need to
obtain spectra of the stars unobservable from the ground. This can
only be done with HST and a reburbished STIS.

COS/NUV/FUV 11598

How Galaxies Acquire their Gas: A Map of Multiphase Accretion and
Feedback in Gaseous Galaxy Halos

We propose to address two of the biggest open questions in galaxy
formation - how galaxies acquire their gas and how they return it to
the IGM - with a concentrated COS survey of diffuse multiphase gas in
the halos of SDSS galaxies at z = 0.15 - 0.35. Our chief science goal
is to establish a basic set of observational facts about the physical
state, metallicity, and kinematics of halo gas, including the sky
covering fraction of hot and cold material, the metallicity of infall
and outflow, and correlations with galaxy stellar mass, type, and
color - all as a function of impact parameter from 10 - 150 kpc.
Theory suggests that the bimodality of galaxy colors, the shape of the
luminosity function, and the mass-metallicity relation are all
influenced at a fundamental level by accretion and feedback, yet these
gas processes are poorly understood and cannot be predicted robustly
from first principles. We lack even a basic observational assessment
of the multiphase gaseous content of galaxy halos on 100 kpc scales,
and we do not know how these processes vary with galaxy properties.
This ignorance is presently one of the key impediments to
understanding galaxy formation in general. We propose to use the
high-resolution gratings G130M and G160M on the Cosmic Origins
Spectrograph to obtain sensitive column density measurements of a
comprehensive suite of multiphase ions in the spectra of 43 z 1 QSOs
lying behind 43 galaxies selected from the Sloan Digital Sky Survey.
In aggregate, these sightlines will constitute a statistically sound
map of the physical state and metallicity of gaseous halos, and
subsets of the data with cuts on galaxy mass, color, and SFR will seek
out predicted variations of gas properties with galaxy properties. Our
interpretation of these data will be aided by state-of-the-art
hydrodynamic simulations of accretion and feedback, in turn providing
information to refine and test such models. We will also use Keck,
MMT, and Magellan (as needed) to obtain optical spectra of the QSOs to
measure cold gas with Mg II, and optical spectra of the galaxies to
measure SFRs and to look for outflows. In addition to our other
science goals, these observations will help place the Milky Way's
population of multiphase, accreting High Velocity Clouds (HVCs) into a
global context by identifying analogous structures around other
galaxies. Our program is designed to make optimal use of the unique
capabilities of COS to address our science goals and also generate a
rich dataset of other absorption-line systems.

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.

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 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.

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 11219

Active Galactic Nuclei in Nearby Galaxies: A New View of the Origin of
the Radio-Loud Radio- Quiet Dichotomy?

Using archival HST and Chandra observations of 34 nearby early-type
galaxies (drawn from a complete radio selected sample) we have found
evidence that the radio-loud/radio-quiet dichotomy is directly
connected to the structure of the inner regions of their host galaxies
in the following sense: [1] Radio-loud AGN are associated with
galaxies with shallow cores in their light profiles [2] Radio-quiet
AGN are only hosted by galaxies with steep cusps. Since the brightness
profile is determined by the galaxy's evolution, through its merger
history, our results suggest that the same process sets the AGN
flavor. This provides us with a novel tool to explore the co-evolution
of galaxies and supermassive black holes, and it opens a new path to
understand the origin of the radio-loud/radio-quiet AGN dichotomy.
Currently our analysis is statistically incomplete as the brightness
profile is not available for 82 of the 116 targets. Most galaxies were
not observed with HST, while in some cases the study is obstructed by
the presence of dust features. We here propose to perform an infrared
NICMOS snapshot survey of these 82 galaxies. This will enable us to i)
test the reality of the dichotomic behavior in a substantially larger
sample; ii) extend the comparison between radio-loud and radio-quiet
AGN to a larger range of luminosities.

WFC3/IR 11202

The Structure of Early-type Galaxies: 0.1-100 Effective Radii

The structure, formation and evolution of early-type galaxies is still
largely an open problem in cosmology: how does the Universe evolve
from large linear scales dominated by dark matter to the highly
non-linear scales of galaxies, where baryons and dark matter both play
important, interacting, roles? To understand the complex physical
processes involved in their formation scenario, and why they have the
tight scaling relations that we observe today (e.g. the Fundamental
Plane), it is critically important not only to understand their
stellar structure, but also their dark-matter distribution from the
smallest to the largest scales. Over the last three years the SLACS
collaboration has developed a toolbox to tackle these issues in a
unique and encompassing way by combining new non-parametric strong
lensing techniques, stellar dynamics, and most recently weak
gravitational lensing, with high-quality Hubble Space Telescope
imaging and VLT/Keck spectroscopic data of early-type lens systems.
This allows us to break degeneracies that are inherent to each of
these techniques separately and probe the mass structure of early-type
galaxies from 0.1 to 100 effective radii. The large dynamic range to
which lensing is sensitive allows us both to probe the clumpy
substructure of these galaxies, as well as their low-density outer
haloes. These methods have convincingly been demonstrated, by our
team, using smaller pilot-samples of SLACS lens systems with HST data.
In this proposal, we request observing time with WFC3 and NICMOS to
observe 53 strong lens systems from SLACS, to obtain complete
multi-color imaging for each system. This would bring the total number
of SLACS lens systems to 87 with completed HST imaging and effectively
doubles the known number of galaxy-scale strong lenses. The deep HST
images enable us to fully exploit our new techniques, beat down
low-number statistics, and probe the structure and evolution of early-
type galaxies, not only with a uniform data-set an order of magnitude
larger than what is available now, but also with a fully-coherent and
self-consistent methodological approach!

NIC3/WFC3/IR 11149

Characterizing the Stellar Populations in Lyman-Alpha Emitters and
Lyman Break Galaxies at 5.7z7 in the Subaru Deep Field

The epoch of reionization marks a major phase transition of the
Universe, during which the intergalactic space became transparent to
UV photons. Determining when this occurred and the physical processes
involved represents the latest frontier in observational cosmology.
Over the last few years, searches have intensified to identify the
population of high-redshift (z6) galaxies that might be responsible
for this process, but the progress is hampered partly by the
difficulty of obtaining physical information (stellar mass, age, star
formation rate/history) for individual sources. This is because the
number of z6 galaxies that have both secure spectroscopic redshifts
and high-quality infrared photometry (especially with Spitzer/IRAC) is
still fairly small. Considering that only several photometric points
are available per source, and that many model SEDs are highly
degenerate, it is crucial to obtain as many observational constraints
as possible for each source to ensure the validity of SED modeling. To
better understand the physical properties of high-redshift galaxies,
we propose here to conduct HST/NICMOS (72 orbits) and Spitzer/IRAC
(102 hours) imaging of spectroscopically confirmed, bright (z26 mag
(AB)) Ly-alpha emitters (LAEs) and Lyman-break galaxies (LBGs) at
5.7z7 selected from the Subaru Deep Field. Spectroscopic redshifts
remove one critical free parameter from SED modeling while bright
source magnitudes ensure high-quality photometric data. By making
accurate determinations of stellar masses, ages, and star-formation
histories, we will specifically address the following major questions:
(1) Do LAEs and LBGs represent physically different galaxy populations
at z6 as suggested recently? (2) Is Ly-alpha emission systematically
suppressed at z6 with respect to continuum emission? (i.e., are we
reaching the epoch of incomplete reionization?), and (3) Do we see any
sign of abnormally young stellar population in any of the z6
galaxies?
 




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