Notice:
Due to the conversion of some ACS WFC or HRC observations into
WFPC2,
or NICMOS observations after the loss of ACS CCD science
capability
in January, there may be an occasional discrepancy between a
proposal's
listed (and correct) instrument usage and the abstract that
follows
it.
HUBBLE
SPACE TELESCOPE - Continuing to collect World Class Science
DAILY
REPORT # 4493
PERIOD
COVERED: UT November 20,21,22,23,24,25, 2007 (DOY 324,325,326,327,328,329)
OBSERVATIONS
SCHEDULED
NIC1/NIC2/NIC3
8794
NICMOS Post-SAA calibration - CR Persistence Part 5
A
new procedure proposed to alleviate the CR-persistence problem of
NICMOS.
Dark frames will be obtained immediately upon exiting the SAA
contour
23, and every time a NICMOS exposure is scheduled within 50
minutes
of coming out of the SAA. The darks will be obtained in parallel
in
all three NICMOS Cameras. The POST-SAA darks will be non- standard
reference
files available to users with a USEAFTER date/time mark. The
keyword
'USEAFTER=date/time' will also be added to the header of each
POST-SAA
DARK frame. The keyword must be populated with the time, in
addition
to the date, because HST crosses the SAA ~8 times per day so
each
POST-SAA DARK will need to have the appropriate time specified, for
users
to identify the ones they need. Both the raw and processed images
will
be archived as POST-SAA DARKs. Generally we expect that all NICMOS
science/calibration
observations started within 50 minutes of leaving an
SAA
will need such maps to remove the CR persistence from the science
images.
Each observation will need its own CRMAP, as different SAA
passages
leave different imprints on the NICMOS detectors.
WFPC2
11289
SL2S:
The Strong Lensing Legacy Survey
Recent
systematic surveys of strong galaxy-galaxy lenses {CLASS, SLACS,
GOODS,
etc.} are producing spectacular results for galaxy masses roughly
below
a transition mass M~10^13 Mo. The observed lens properties and
their
evolution up to z~0.2, consistent with numerical simulations, can
be
described by isothermal elliptical potentials. In contrast, modeling
of
giant arcs in X-ray luminous clusters {halo masses M >~10^13 Mo}
favors
NFW mass profiles, suggesting that dark matter halos are not
significantly
affected by baryon cooling. Until recently, lensing
surveys
were neither deep nor extended enough to probe the intermediate
mass
density regime, which is fundamental for understanding the assembly
of
structures. The CFHT Legacy Survey now covers 125 square degrees, and
thus
offers a large reservoir of strong lenses probing a large range of
mass
densities up to z~1. We have extracted a list of 150 strong lenses
using
the most recent CFHTLS data release via automated procedures.
Following
our first SNAPSHOT proposal in cycle 15, we propose to
continue
the Hubble follow-up targeting a larger list of 130 lensing
candidates.
These are intermediate mass range candidates {between
galaxies
and clusters} that are selected in the redshift range of 0.2-1
with
no a priori X-ray selection. The HST resolution is necessary for
confirming
the lensing candidates, accurate modeling of the lenses, and
probing
the total mass concentration in galaxy groups up to z~1 with the
largest
unbiased sample available to date.
ACS/SBC
11225
The
Wavelength Dependence of Accretion Disk Structure
We
can now routinely measure the size of quasar accretion disks using
gravitational
microlensing of lensed quasars. The next step to testing
accretion
disk models is to measure the size of accretion disks as a
function
of wavelength, particularly at the UV and X-ray wavelengths
that
should probe the inner, strong gravity regime. Here we focus on two
four-image
quasar lenses that already have optical {R band} and X-ray
size
measurements using microlensing. We will combine the HST
observations
with ground-based monitoring to measure the disk size as a
function
of wavelength from the near-IR to the UV. We require HST to
measure
the image flux ratios in the ultraviolet continuum near the
Lyman
limit of the quasars. The selected targets have estimated black
hole
masses that differ by an order of magnitude, and we should find
wavelength
scalings for the two systems that are very different because
the
Blue/UV wavelengths should correspond to parts of the disk near the
inner
edge for the high mass system but not in the low mass system. The
results
will be modeled using a combination of simple thin disk models
and
complete relativistic disk models. While requiring only 18 orbits,
success
for one system requires observations in both Cycles 16 and 17.
WFPC2
11222
Direct
Detection and Mapping of Star Forming Regions in Nearby, Luminous
Quasars
We
propose to carry out narrow-band emission line imaging observations
of
8 quasars at z=0.05-0.15 with the WFPC2 ramp filters and with the
NICMOS
narrow-band filters. We will obtain images in the [O II], [O
III],
H-beta, and Pa-alpha emission line bands to carry out a series of
diagnostic
tests aimed at detecting and mapping out star-forming regions
in
the quasar host galaxies. This direct detection of star-forming
regions
will confirm indirect indications for star formation in quasar
host
galaxies. It will provide a crucial test for models of quasar and
galaxy
evolution, that predict the co-existence of starbursts and
"monsters"
and will solve the puzzle of why different indicators of star
formation
give contradictory results. A secondary science goal is to
assess
suggested correlations between quasar luminosity and the size of
the
narrow-line region.
WFPC2
11216
HST
/ Chandra Monitoring of a Dramatic Flare in the M87 Jet
As
the nearest galaxy with an optical jet, M87 affords an unparalleled
opportunity
to study extragalactic jet phenomena at the highest
resolution.
During 2002, HST and Chandra monitoring of the M87 jet
detected
a dramatic flare in knot HST-1 located ~1" from the nucleus.
Its
optical brightness eventually increased seventy-fold and peaked in
2005;
the X- rays show a similarly dramatic outburst. In both bands
HST-1
is still extremely bright and greatly outshines the galaxy
nucleus.
To our knowledge this is the first incidence of an optical or
X-ray
outburst from a jet region which is spatially distinct from the
core
source -- this presents an unprecedented opportunity to study the
processes
responsible for non- thermal variability and the X-ray
emission.
We propose five epochs of HST/WFPC2 flux monitoring during
Cycle
16, as well as seven epochs of Chandra/ACIS observation {5ksec
each,
six Chandra epochs contemporary with HST}. At two of the HST/WFPC2
epochs
we also gather spectral information, and at one epoch we will map
the
magnetic field structure. The results of this investigation are of
key
importance not only for understanding the nature of the X-ray
emission
of the M87 jet, but also for understanding flares in blazar
jets,
which are highly variable, but where we have never before been
able
to resolve the flaring region in the optical or X-rays. These new
observations
will allow us to track the decay phase of the giant flare,
and
study smaller secondary flares such as seen late in 2006. Ultimately
we
will test synchrotron emission models for the X-ray outburst,
constrain
particle acceleration and loss timescales, and study the jet
dynamics
associated with this flaring component.
FGS
11211
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
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.
WEPC2
11196
An
Ultraviolet Survey of Luminous Infrared Galaxies in the Local
Universe
At
luminosities above 10^11.4 L_sun, the space density of far-infrared
selected
galaxies exceeds that of optically selected galaxies. These
Luminous
Infrared Galaxies {LIRGs} are primarily interacting or merging
disk
galaxies undergoing starbursts and creating/fueling central AGN. We
propose
far {ACS/SBC/F140LP} and near {WFPC2/PC/F218W} UV imaging of a
sample
of 27 galaxies drawn from the complete IRAS Revised Bright Galaxy
Sample
{RBGS} LIRGs sample and known, from our Cycle 14 B and I-band ACS
imaging
observations, to have significant numbers of bright {23 < B < 21
mag}
star clusters in the central 30 arcsec. The HST UV data will be
combined
with previously obtained HST, Spitzer, and GALEX images to {i}
calculate
the ages of the clusters as function of merger stage, {ii}
measure
the amount of UV light in massive star clusters relative to
diffuse
regions of star formation, {iii} assess the feasibility of using
the
UV slope to predict the far- IR luminosity {and thus the star
formation
rate} both among and within IR-luminous galaxies, and {iv}
provide
a much needed catalog of rest-frame UV morphologies for
comparison
with rest-frame UV images of high-z LIRGs and Lyman Break
Galaxies.
These observations will achieve the resolution required to
perform
both detailed photometry of compact structures and spatial
correlations
between UV and redder wavelengths for a physical
interpretation
our IRX-Beta results. The HST UV data, combined with the
HST
ACS, Spitzer, Chandra, and GALEX observations of this sample, will
result
in the most comprehensive study of luminous starburst galaxies to
date.
WFPC2
11178
Probing
Solar System History with Orbits, Masses, and Colors of
Transneptunian
Binaries
The
recent discovery of numerous transneptunian binaries {TNBs} opens a
window
into dynamical conditions in the protoplanetary disk where they
formed
as well as the history of subsequent events which sculpted the
outer
Solar System and emplaced them onto their present day heliocentric
orbits.
To date, at least 47 TNBs have been discovered, but only about a
dozen
have had their mutual orbits and separate colors determined,
frustrating
their use to investigate numerous important scientific
questions.
The current shortage of data especially cripples scientific
investigations
requiring statistical comparisons among the ensemble
characteristics.
We propose to obtain sufficient astrometry and
photometry
of 23 TNBs to compute their mutual orbits and system masses
and
to determine separate primary and secondary colors, roughly tripling
the
sample for which this information is known, as well as extending it
to
include systems of two near-equal size bodies. To make the most
efficient
possible use of HST, we will use a
optimally
schedule our observations.
WFPC2
11176
Location
and the Origin of Short Gamma-Ray Bursts
During
the past decade extraordinary progress has been made in
determining
the origin of long-duration gamma-ray bursts. It has been
conclusively
shown that these objects derive from the deaths of massive
stars.
Nonetheless, the origin of their observational cousins,
short-duration
gamma-ray bursts {SGRBs} remains a mystery. While SGRBs
are
widely thought to result from the inspiral of compact binaries, this
is
a conjecture. A number of hosts of SGRBs have been identified, and
have
been used by some to argue that SGRBs derive primarily from an
ancient
population {~ 5 Gyr}; however, it is not known whether this
conclusion
more accurately reflects selection biases or astrophysics.
Here
we propose to employ a variant of a technique that we pioneered and
used
to great effect in elucidating the origins of long-duration bursts.
We
will examine the degree to which SGRB locations trace the red or blue
light
of their hosts, and thus old or young stellar populations. This
approach
will allow us to study the demographics of the SGRB population
in
a manner largely free of the distance dependent selection effects
which
have so far bedeviled this field, and should give direct insight
into
the age of the SGRB progenitor population.
ACS/SBC
WFPC2 11175
UV
Imaging to Determine the Location of Residual Star Formation in
Galaxies
Recently Arrived on the Red Sequence
We
have identified a sample of low-redshift {z = 0.04 - 0.10} galaxies
that
are candidates for recent arrival on the red sequence. They have
red
optical colors indicative of old stellar populations, but blue
UV-optical
colors that could indicate the presence of a small quantity
of
continuing or very recent star formation. However, their spectra lack
the
emission lines that characterize star-forming galaxies. We propose
to
use ACS/SBC to obtain high- resolution imaging of the UV flux in
these
galaxies, in order to determine the spatial distribution of the
last
episode of star formation. WFPC2 imaging will provide B, V, and I
photometry
to measure the main stellar light distribution of the galaxy
for
comparison with the UV imaging, as well as to measure color
gradients
and the distribution of interstellar dust. This detailed
morphological
information will allow us to investigate the hypothesis
that
these galaxies have recently stopped forming stars and to compare
the
observed distribution of the last star formation with predictions
for
several different mechanisms that may quench star formation in
galaxies.
NIC2
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.
WFPC2
11134
WFPC2
Tidal Tail Survey: Probing Star Cluster Formation on the Edge
The
spectacular HST images of the interiors of merging galaxies such as
the
Antennae and NGC 7252 have revealed rich and diverse populations of
star
clusters created over the course of the interaction. Intriguingly,
our
WFPC2 study of tidal tails in these and other interacting pairs has
shown
that star cluster birth in the tails does not follow a similarly
straightforward
evolution. In fact, cluster formation in these
relatively
sparse environments is not guaranteed -- only one of six
tails
in our initial study showed evidence for a significant population
of
young star clusters. The tail environment thus offers the opportunity
to
probe star cluster formation on the edge of the physical parameter
space
{e.g., of stellar and gas mass, density, and pressure} that
permits
it to occur. We propose to significantly extend our pilot sample
of
optically bright, gas-rich tidal tails by a factor of 4 in number to
include
a more diverse population of tails, encompassing major and minor
mergers,
gas-rich and gas-poor tails, as well as early, late, and merged
interaction
stages. With 21 orbits of HST WFPC2 imaging in the F606W and
F814W
filters, we can identify, roughly age-date, and measure sizes of
star
clusters to determine what physical parameters affect star cluster
formation.
WFPC2 imaging has been used effectively in our initial study
of
four mergers, and it will be possible in this program to reach
similar
limits of Mv=-8.5 for each of 16 more tails. With the much
larger
sample we expect to isolate which factors, such as merger stage,
HI
content, and merger mass ratio, drive the formation of star clusters.
WFPC2
11130
AGNs
with Intermediate-mass Black Holes: Testing the Black Hole-Bulge
Paradigm,
Part II
The
recent progress in the study of central black holes in galactic
nuclei
has led to a general consensus that supermassive {10^6-10^9 solar
mass}
black holes are closely connected with the formation and
evolutionary
history of large galaxies, especially their bulge
component.
Two outstanding issues, however, remain unresolved. Can
central
black holes form in the absence of a bulge? And does the mass
function
of central black holes extend below 10^6 solar masses?
Intermediate-mass
black holes {<10^6 solar masses}, if they exist, may
offer
important clues to the nature of the seeds of supermassive black
holes.
Using the SDSS, our group has successfully uncovered a new
population
of AGNs with intermediate-mass black holes that reside in
low-luminosity
galaxies. However, very little is known about the
detailed
morphologies or structural parameters of the host galaxies
themselves,
including the crucial question of whether they have bulges
or
not. Surprisingly, the majority of the targets of our Cycle 14 pilot
program
have structural properties similar to dwarf elliptical galaxies.
The
statistics from this initial study, however, are really too sparse
to
reach definitive conclusions on this important new class of black
holes.
We wish to extend this study to a larger sample, by using the
Snapshot
mode to obtain WFPC2 F814W images from a parent sample of 175
AGNs
with intermediate-mass black holes selected from our final SDSS
search.
We are particularly keen to determine whether the hosts contain
bulges,
and if so, how the fundamental plane properties of the host
depend
on the mass of their central black holes. We will also
investigate
the environment of this unique class of AGNs.
WFPC2
11128
Time
Scales Of Bulge Formation In Nearby Galaxies
Traditionally,
bulges are thought to fit well into galaxy formation
models
of hierarchical merging. However, it is now becoming well
established
that many bulges formed through internal, secular evolution
of
the disk rather than through mergers. We call these objects
pseudobulges.
Much is still unknown about pseudobulges, the most
pressing
questions being: How, exactly, do they build up their mass? How
long
does it take? And, how many exist? We are after an answer to these
questions.
If pseudobulges form and evolve over longer periods than the
time
between mergers, then a significant population of pseudobulges is
hard
to explain within current galaxy formation theories. A pseudobulge
indicates
that a galaxy has most likely not undergone a major merger
since
the formation of the disk. The ages of pseudobulges give us an
estimate
for the time scale of this quiescent evolution. We propose to
use
24 orbits of HST time to complete UBVIH imaging on a sample of 33
nearby
galaxies that we have observed with Spitzer in the mid-IR. These
data
will be used to measure spatially resolved stellar population
parameters
{mean stellar age, metallicity, and star formation history};
comparing
ages to star formation rates allows us to accurately constrain
the
time scale of pseudobulge formation. Our sample of bulges includes
both
pseudo- and classical bulges, and evenly samples barred and
unbarred
galaxies. Most of our sample is imaged, 13 have complete UBVIH
coverage;
we merely ask to complete missing observations so that we may
construct
a uniform sample for studying bulge formation. We also wish to
compare
the stellar population parameters to a variety of bulge and
global
galaxy properties including star formation rates, dynamics,
internal
bulge morphology, structure from bulge-disk decompositions, and
gas
content. Much of this data set is already or is being assembled.
This
will allow us to derive methods of pseudobulge identification that
can
be used to accurately count pseudobulges in large surveys. Aside
from
our own science goals, we will present this broad set of data to
the
community. Thus, we waive proprietary periods for all observations.
WFPC2
11126
Resolving
the Smallest Galaxies
An
order of magnitude more dwarf galaxies are expected to inhabit the
Local
Group, based on currently accepted galaxy formation models, than
have
been observed. This discrepancy has been noted in environments
ranging
from the field to rich clusters, with evidence emerging that
lower
density regions contain fewer dwarfs per giant than higher density
regions,
in further contrast to model predictions. One possible
explanation
for this involves the effects of reionization on the forming
galaxies
and naturally explains both the dearth of dwarf galaxies and
the
apparent environmental dependence. However, before such theories can
be
fully tested, we require a better understanding of the distribution
of
dwarf galaxies. Currently, there is no complete census of the
faintest
dwarf galaxies in any environment. The discovery of the
smallest
and faintest dwarfs is hampered by the limitations in detecting
such
faint and low surface brightness galaxies, and this is compounded
by
the great difficulty in determining accurate distances to, or
ascertaining
group membership for, such faint objects. The M81 group
provides
a unique means for establishing membership for galaxies in a
low
density region complete to magnitudes as faint as M_R ~ -7. With a
distance
modulus of 27.8, the tip of the red giant branch {TRGB} appears
at
I ~ 24, just within the reach of ground based surveys. We currently
have
surveyed a 30 square degree region around M81 with the
CFHT/Megacam.
From these images we have detected 15 new candidate dwarf
galaxies.
We propose to use the HST with WFPC2 to image these 15
galaxies
in F606W and F814W bands in order to construct a
color-magnitude
diagram down to I = 25.5 from which to measure accurate
TRGB
distances to these candidate galaxies and determine star formation
and
metallicity histories. The overall project will provide a survey of
the
dwarf galaxies in the M81 group environment with unprecedented
completeness
to a limit of M_R < -7.
ACS/SBC
11109
Characterization
of the UV absorption feature in asteroid {1} Ceres
We
propose to obtain the UV spectrum of asteroid {1} Ceres from 120 nm
to
200 nm with ACS/SBC objective prism to characterize the broad and
deep
absorption feature within this wavelength range as reported by ACS
observations
of Ceres in 2003/04 {Li et al. 2006}. Our scientific goals
include,
1} to characterize the absorption band, 2} to determine the
origin
of this spectral feature and constrain the surface composition of
Ceres,
and 3} to understand the albedo and color features on Ceres. HST
is
the only observatory currently capable of obtaining spectroscopy in
this
wavelength range. This observation will help improve our knowledge
about
this largest and oldest asteroid, and support the planning of the
upcoming
NASA Discovery Program mission, Dawn, orbiting asteroids Vesta
and
Ceres.
WFPC2
11103
A
Snapshot Survey of The Most Massive Clusters of Galaxies
We
propose the continuation of our highly successful SNAPshot survey of
a
sample of 125 very X-ray luminous clusters in the redshift range
0.3-0.7.
As demonstrated by the 25 snapshots obtained so far in Cycle14
and
Cycle15 these systems frequently exhibit strong gravitational
lensing
as well as spectacular examples of violent galaxy interactions.
The
proposed observations will provide important constraints on the
cluster
mass distributions, the physical nature of galaxy-galaxy and
galaxy-gas
interactions in cluster cores, and a set of optically bright,
lensed
galaxies for further 8-10m spectroscopy. All of our primary
science
goals require only the detection and characterization of
high-surface-brightness
features and are thus achievable even at the
reduced
sensitivity of WFPC2. Because of their high redshift and thus
compact
angular scale our target clusters are less adversely affected by
the
smaller field of view of WFPC2 than more nearby systems.
Acknowledging
the broad community interest in this sample we waive our
data
rights for these observations. Due to a clerical error at STScI our
approved
Cycle15 SNAP program was barred from execution for 3 months and
only
6 observations have been performed to date - reinstating this SNAP
at
Cycle16 priority is of paramount importance to reach meaningful
statistics.
NIC2
11101
The
Relevance of Mergers for Fueling AGNs: Answers from QSO Host
Galaxies
The
majority of QSOs are known to reside in centers of galaxies that
look
like ellipticals. Numerical simulations have shown that remnants of
galaxy
mergers often closely resemble elliptical galaxies. However, it
is
still strongly debated whether the majority of QSO host galaxies are
indeed
the result of relatively recent mergers or whether they are
completely
analogous to inactive ellipticals to which nothing
interesting
has happened recently. To address this question, we recently
obtained
deep HST ACS images for five QSO host galaxies that were
classified
morphologically as ellipticals {GO-10421}. This pilot study
revealed
striking signs of tidal interactions such as ripples, tidal
tails,
and warped disks that were not detected in previous studies. Our
observations
show that at least some "elliptical" QSO host galaxies are
the
products of relatively recent merger events rather than old galaxies
formed
at high redshift. However, the question remains whether the host
galaxies
of classical QSOs are truly distinct from inactive ellipticals
and
whether there is a connection between the merger events we detect
and
the current nuclear activity. We must therefore place our results
into
a larger statistical context. We are currently conducting an HST
archival
study of inactive elliptical galaxies {AR-10941} to form a
control
sample. We now propose to obtain deep HST/WFPC2 images of 13
QSOs
whose host galaxies are classified as normal ellipticals. Comparing
the
results for both samples will help us determine whether classical
QSOs
reside in normal elliptical galaxies or not. Our recent pilot study
of
five QSOs indicates that we can expect exciting results and deep
insights
into the host galaxy morphology also for this larger sample of
QSOs.
A statistically meaningful sample will help us determine the true
fraction
of QSO hosts that suffered strong tidal interactions and thus,
whether
a merger is indeed a requirement to trigger nuclear activity in
the
most luminous AGNs. In addition to our primary science observations
with
WFPC2, we will obtain NICMOS3 parallel observations with the
overall
goal to select and characterize galaxy populations at high
redshifts.
The imaging will be among the deepest NICMOS images: These
NICMOS
images are expected to go to a limit a little over 1 magnitude
brighter
than HUDF-NICMOS data, but over 13 widely separated fields,
with
a total area about 1.5 times larger than HUDF-NICMOS. This
separation
means that the survey will tend to average out effects of
cosmic
variance. The NICMOS3 images will have sufficient resolution for
an
initial characterization of galaxy morphologies, which is currently
one
of the most active and promising areas in approaching the problem of
the
formation of the first massive galaxies. The depth and area coverage
of
our proposed NICMOS observations will also allow a careful study of
the
mass function of galaxies at these redshifts. This provides a large
and
unbiased sample, selected in terms of stellar mass and unaffected by
cosmic
variance, to study the on-going star formation activity as a
function
of mass {i.e. integrated star formation} at this very important
epoch.
NIC3
11082
NICMOS
Imaging of GOODS: Probing the Evolution of the Earliest Massive
Galaxies,
Galaxies Beyond Reionization, and the High Redshift Obscured
Universe
(uses
ACS/SBC and WFPC2)
Deep
near-infrared imaging provides the only avenue towards
understanding
a host of astrophysical problems, including: finding
galaxies
and AGN at z > 7, the evolution of the most massive galaxies,
the
triggering of star formation in dusty galaxies, and revealing
properties
of obscured AGN. As such, we propose to observe 60 selected
areas
of the GOODS North and South fields with NICMOS Camera 3 in the
F160W
band pointed at known massive M > 10^11 M_0 galaxies at z > 2
discovered
through deep Spitzer imaging. The depth we will reach {26.5
AB
at 5 sigma} in H_160 allows us to study the internal properties of
these
galaxies, including their sizes and morphologies, and to
understand
how scaling relations such as the Kormendy relationship
evolved.
Although NIC3 is out of focus and under sampled, it is currently
our
best opportunity to study these galaxies, while also sampling enough
area
to perform a general NIR survey 1/3 the size of an ACS GOODS field.
These
data will be a significant resource, invaluable for many other
science
goals, including discovering high redshift galaxies at z > 7,
the
evolution of galaxies onto the Hubble sequence, as well as examining
obscured
AGN and dusty star formation at z > 1.5. The GOODS fields are
the
natural location for HST to perform a deep NICMOS imaging program,
as
extensive data from space and ground based observatories such as
Chandra,
GALEX, Spitzer, NOAO, Keck, Subaru, VLT, JCMT, and the VLA are
currently
available for these regions. Deep high-resolution
near-infrared
observations are the one missing ingredient to this
survey,
filling in an important gap to create the deepest, largest, and
most
uniform data set for studying the faint and distant universe. The
importance
of these images will increase with time as new facilities
come
on line, most notably WFC3 and ALMA, and for the planning of future
JWST
observations.
WFPC2
11035
Photometric
Zero Points Closeout
Updated
zero points will be obtained by observing NGC 2419 for which
extensive
BVRI ground based observations exist, and the field in 47 Tuc
used
for frequent monitoring of ACS. For NGC 2419 emphasis is given to
repeating
observations obtained in earlier epochs, and to covering
filters
near standard BVRI. For 47 Tuc emphasis is given to covering a
large
set of broadband filters from F300W through F850LP to maximise
transformation
capabilities between filters of WFPC2 and ACS.
WFPC2
10798
Dark
Halos and Substructure from Arcs & Einstein Rings
The
surface brightness distribution of extended gravitationally lensed
arcs
and Einstein rings contains super-resolved information about the
lensed
object, and, more excitingly, about the smooth and clumpy mass
distribution
of the lens galaxies. The source and lens information can
non-parametrically
be separated, resulting in a direct "gravitational
image"
of the inner mass-distribution of cosmologically-distant galaxies
{Koopmans 2005; Koopmans et al. 2006 [astro-ph/0601628]}. With
this goal
in mind,
we propose deep HST ACS-F555W/F814W and NICMOS-F160W WFC
imaging
of 20 new gravitational-lens systems with spatially resolved
lensed
sources, of the 35 new lens systems discovered by the Sloan Lens
ACS
Survey {Bolton et al. 2005} so far, 15 of which are being imaged in
Cycle-14.
Each system has been selected from the SDSS and confirmed in
two
time- efficient HST-ACS snapshot programs {cycle 13&14}.
High-fidelity
multi-color HST images are required {not delivered by the
420s
snapshots} to isolate these lensed images {properly cleaned,
dithered
and extinction-corrected} from the lens galaxy surface
brightness
distribution, and apply our "gravitational maging" technique.
Our
sample of 35 early-type lens galaxies to date is by far the largest,
still
growing, and most uniformly selected. This minimizes selection
biases
and small-number statistics, compared to smaller, often
serendipitously
discovered, samples. Moreover, using the WFC provides
information
on the field around the lens, higher S/N and a better
understood
PSF, compared with the HRC, and one retains high spatial
resolution
through drizzling. The sample of galaxy mass distributions -
determined
through this method from the arcs and Einstein ring HST
images
- will be studied to: {i} measure the smooth mass distribution of
the
lens galaxies {dark and luminous mass are separated using the HST
images
and the stellar M/L values derived from a joint stellar-dynamical
analysis
of each system}; {ii} quantify statistically and individually
the
incidence of mass-substructure {with or without obvious luminous
counter-
parts such as dwarf galaxies}. Since dark-matter substructure
could
be more prevalent at higher redshift, both results provide a
direct
test of this prediction of the CDM hierarchical
structure-formation
model.
FLIGHT
OPERATIONS SUMMARY:
Significant
Spacecraft Anomalies: (The following are preliminary reports
of
potential non-nominal performance that will be investigated.)
HSTARS:
11076
- GSacq(1,3,1) failed, Scan Step Limit exceeded on FGS 1
GSACQ(1,3,1) at 326/06:01:11 failed due to scan step limit
exceeded on
FGS 1 while vehicle was LOS. No ESB messages were received, #44
commands
did not update from their values prior to LOS.
11077
- REacq(1,2,2) failed to RGA Hold
At AOS at 326/12:16:45, REacq(1,2,2) scheduled at 11:46:45 had
failed to
RGA hold due to receiving QF1STOPF on FGA 1. OBAD2 had RSS value
of 2.44
arcseconds.
11078
- GSacq(1,2,1) failed, Search Radius Limit exceeded on FGS 1
GSacq(1,2,1) at 327/08:13:07 failed at 08:18:58 with search radius
limit
exceeded on FGS 1. One 486 status buffer "A05" message
(FGS Coarse Track
failed- search Radius Limit exceeded) was received. OBAD prior to
GSACQ
had RSS error of 14.39 arcseconds.
11079
- GSacq(1,3,1) not attempted, Open Loop Timer expired
GSACQ(1,3,1) at 330/04:14:05 failed while vehicle was LOS, was not
attempted due to open loop timer expiration. 27 ESB messages were
received beginning at 04:11:31, see attached dump file.
COMPLETED
OPS REQUEST: (None)
COMPLETED
OPS NOTES: (None)
SCHEDULED
SUCCESSFUL
FGS
GSacq
43
40
FGS
REacq
26
25
OBAD
with Maneuver 134
134
SIGNIFICANT
EVENTS: (None)