HUBBLE
SPACE TELESCOPE - Continuing to collect World Class Science
DAILY
REPORT #4637
PERIOD
COVERED: 5am June 20 - 5am June 23, 2008 (DOY 172/0900z-175/0900z)
OBSERVATIONS
SCHEDULED
NIC1/NIC2/NIC3
8795
NICMOS Post-SAA Calibration - CR Persistence Part 6
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 DARKSs. 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 i
mages.
Each observation will need its own CRMAP, as different SAA
passages
leave different imprints on the NICMOS detectors.
WFPC2
11235
HST
NICMOS Survey of the Nuclear Regions 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 enhanced star formation and Active
Galactic
Nuclei {AGN} activity, possibly triggered as the objects
transform
into massive S0 and elliptical merger remnants. We propose
NICMOS
NIC2 imaging of the nuclear regions of a complete sample of 88
L_IR
> 10^11.4 L_sun luminous infrared galaxies in the IRAS Revised
Bright
Galaxy Sample {RBGS: i.e., 60 micron flux density > 5.24 Jy}.
This
sample is ideal not only in its completeness and sample size, but
also
in the proximity and brightness of the galaxies. The superb
sensitivity
and resolution of NICMOS NIC2 on HST enables a unique
opportunity
to study the detailed structure of the nuclear regions,
where
dust obscuration may mask star clusters, AGN and additional nuclei
from
optical view, with a resolution significantly higher than possible
with
Spitzer IRAC. This survey thus provides a crucial component to our
study
of the dynamics and evolution of IR galaxies presently underway
with
Wide-Field, HST ACS/WFC and Spitzer IRAC observations of these 88
galaxies.
Imaging will be done with the F160W filter {H-band} to examine
as
a function of both luminosity and merger stage {i} the luminosity and
distribution
of embedded star clusters, {ii} the presence of optically
obscured
AGN and nuclei, {iii} the correlation between the distribution
of
1.6 micron emission and the mid- IR emission as detected by Spitzer
IRAC,
{iv} the evidence of bars or bridges that may funnel fuel into the
nuclear
region, and {v} the ages of star clusters for which photometry
is
available via ACS/WFC observations. The NICMOS data, combined with
the
HST ACS, Spitzer, and GALEX observations of this sample, will result
in
the most comprehensive study of merging and interacting galaxies to
date.
WFPC2
11233
Multiple
Generations of Stars in Massive Galactic Globular Clusters
This
is a follow-up to recent HST imaging of NGC 2808, which discovered
that
its main sequence is triple, with three well-separated parallel
branches
{Fig.~1}. Along with the double MS of Omega Centauri, this
challenges
the long-held paradigm that globular clusters are simple,
single
stellar populations. The cause of this main sequence multiplicity
in
both clusters is likely to be differences in helium abundance, which
could
play a fundamental role in the understanding of stellar
populations.
We propose to image seven more of the most massive globular
clusters,
to examine their main sequences for indications of splitting.
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 W Vir
stars.
The Population II Cepheids lie with the RR Lyrae stars on a
common
K-band Period-Luminosity relation. Using these parallaxes to
inform
that relationship, we anticipate a zero-point error of 0.04
magnitude.
This result should greatly strengthen confidence in the
Population
II distance scale and increase our understanding of RR Lyrae
star
and Pop II Cepheid astrophysics.
WFPC2
11206
At the
Cradle of the Milky Way: Formation of the Most Massive Field Disk
Galaxies
at z>1
We
propose to obtain 2 orbit WFPC2 F814W images of a sample of the 15
most
massive galaxies found at $1 < z < 1.3$. These were culled from
over
20,000 Keck spectra collected as part of DEEP and are unique among
high
redshift massive galaxy samples in being kinematically selected.
Through
a recent HST NICMOS-2 imaging program {GO-10532}, we have
confirmed
that these galaxies have regular stellar disks, and their
emission
line kinematics are not due to gradients from merging
components.
These potentially very young galaxies are likely precursors
to
massive local disks, assuming no further merging. The proposed WFPC2
and
existing NIC-2 data provide colors, stellar masses, and ages of
bulge
and disk subcomponents, to assess whether old stellar bulges and
disks
are in place at that time or still being built, and constrain
their
formation epochs. Finally, this sample will yield the first
statistically
significant results on the $z > 1$ evolution of the
size-velocity-luminosity
scaling relations, for massive galaxies at
different
wavelengths, and constrain whether this evolution reflects
stellar
mass growth, or passive evolution, of either bulge or disk
components.
WFPC2
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
WFPC2
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!
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.
NIC3
11147
The
Origin of Diffuse UV Light from Spiral Disks
The
ultraviolet light from galaxies has been used as a beacon for
tracing
the cosmic star formation history of the Universe, yet we have
an
incomplete understanding of many characteristics of this light. Most
of
the UV emission from nearby, normal star--forming galaxies is
unresolved
and "diffuse", and GALEX has shown that in spiral disks it
permeates
the inter-arm regions. The nature of this diffuse inter- arm
component
is under debate. Recent results suggest that it may arise from
non-
ionizing UV photons which originate in star forming regions in the
spiral
arms, travel in the plane of the galaxy, and then scatter off of
diffusely
distributed cold dust grains. Alternatively, an in-situ,
unresolved
stellar population could produce the observed inter-arm UV
emission.
This project seeks to establish which of the two competing
scenarios
is responsible for the bulk of this diffuse emission. We
propose
to use HST's UV imaging capability (ACS/SBC) to obtain deep
observations
of selected fields in the nearby spiral galaxy M101, for
which
available (low angular resolution) data favor the 'scattered
light'
scenario. Our observations are designed to detect any faint,
UV-luminous
stellar population down to main sequence B5 stars. With
these
data, we will establish the nature of the bulk of the diffuse UV
light
in this spiral galaxy by: (i) quantifying the contribution from
dust-scattered
light; (ii) measuring the contribution to the ubiquitous
diffuse
ionized medium from in- situ ionizing stars; and (iii) providing
constraints
on the observed stellar mass function in the field. Only HST
has
the UV sensitivity and angular resolution to discriminate in-situ
stellar
populations from scattered light. The ultimate goal of this
project
is to re-'calibrate' the UV emission as a star formation rate
indicator,
which will need to account for any scattered component.
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
11137
First
Accurate Geometric Distance to a Galactic Wolf-Rayet Star: Knots
in
the Ejecta M1-67
M
1-67 is the youngest known ejection nebula surrounding a Population I
Wolf-Rayet
star, in this case the WN8 star WR 124. Our deep H-alpha
HST/WFPC2
image of this object in March 1997 revealed, for the first
time
in such a nebula, numerous bright, mostly unresolved knots (typical
diameters
0.1-0.2") often surrounded by what appear to be their own
local
spherical diffuse 'wind' bubbles. We propose to obtain a second
epoch
H-alpha image of M 1-67, essentially repeating the Epoch1
instrumental
set-up. By measuring the proper motions of the knots, we
will
derive a relatively precise and assumption-free geometric distance
(thus
also a luminosity) to a Galactic Wolf-Rayet star, the first of its
kind.
This will help to confirm the suspected runaway status of WR 124
and
shed new light on the nature of progenitors of gamma-ray bursts.
Moreover,
we intend to document and measure the anticipated
morphology/brightness
changes in the fine-stucture features of the
nebula
over the 11-year interval, as they relate to wind-embedded
shocks.
This will provide important input for interaction models of a
stellar
wind with circumstellar matter.
ACS/SBC
11110
Searching
for Lyman Apha Emission from FUSE Lyman Continuum Candidates
We
have recently been granted time on FUSE to characterize the escape
fraction
of hydrogen Lyman continuum (Lyc) photons from a
morphologically
diverse set of star forming galaxies. The FUSE program
is
designed to provide ~ 5 sigma detections of Lyc photons emitted from
star
forming galaxies with escape fractions ~5%. With this proposal we
seek
hydrogen Lyman alpha (Lya) observations of a representative subset
of
the FUSE program targets to constrain the observational relationship
between
Lyc, Lya, and hydrogen Balmer line emission in these systems.
Such
observations explore the detailed balance between the simple
optically
thin (Case A) and optically thick (Case B) limits in
recombination
theory. The ultimate goal of this program is to quantify
the
relationship between escaping Lya and Lyc emission and the first
structures
that form in the early universe.
WFPC2
11079
Treasury
Imaging of Star Forming Regions in the Local Group:
Complementing
the GALEX and NOAO Surveys
We
propose to use WFPC2 to image the most interesting star-forming
regions
in the Local Group galaxies, to resolve their young stellar
populations.
We will use a set of filters including F170W, which is
critical
to detect and characterize the most massive stars, to whose hot
temperatures
colors at longer wavelengths are not sensitive. WFPC2's
field
of view ideally matches the typical size of the star-forming
regions,
and its spatial resolution allows us to measure individual
stars,
given the proximity of these galaxies. The resulting H-R diagrams
will
enable studies of star-formation properties in these regions, which
cover
largely differing metallicities {a factor of 17, compared to the
factor
of 4 explored so far} and characteristics. The results will
further
our understanding of the star-formation process, of the
interplay
between massive stars and environment, the properties of dust,
and
will provide the key to interpret integrated measurements of
star-formation
indicators {UV, IR, Halpha} available for several
hundreds
more distant galaxies. Our recent deep surveys of these
galaxies
with GALEX {FUV, NUV} and ground-based imaging {UBVRI, Halpha,
[OIII]
and [SII]} provided the identification of the most relevant SF
sites.
In addition to our scientific analysis, we will provide catalogs
of HST
photometry in 6 bands, matched corollary ground-based data, and
UV,
Halpha and IR integrated measurements of the associations, for
comparison
of integrated star-formation indices to the resolved
populations.
We envisage an EPO component.
WFPC2
11032
CTE
Extended Targets Closeout
Measuring
the charge transfer efficiency {CTE} of an astronomical CCD
camera
is crucial to determining the CCD's photometric fidelity across
the
field of view. WFPC2's CTE has degraded steadily over the last 13
years
because of continuous exposure to trapped particles in HST's
radiation
environment. The fraction of photometric signal lost from
WFPC2's
CTI {change transfer inefficiency} is a function of WFPC2's time
in
orbit, the integrated signal in the image, the location of the image
on
the CCD, and the background signal. Routine monitoring of WFPC2's
degrading
CTE over the last 13 years has primarily concerned the effects
of
CTI on point-source photometry. However, most of the sources imaged
by
WFPC2 are extended rather than point- like. This program aims to
characterize
the effects of CTI on the photometry and morphology of
extended
sources near the end of WFPC2's functional life. Images of a
standard
field within the rich galaxy cluster Abell 1689 are recorded
with
each WFPC2 camera using the F606W and F814W filters. These images
will
be compared with contemporaneous images of Abell 1689 recorded with
the
field rotated by approximately 180 degrees to assess differences
between
extended sources imaged near and far from the serial register.
The
images will also be compared with similar images recorded in Cycle 8
{Program
8456} to characterize the rate of CTE degradation over the
lifetime
of WFPC2.
WFPC2
11022
WFPC2
Cycle 15 Decontaminations and Associated Observations
This
proposal is for the WFPC2 decons. Also included are instrument
monitors
tied to decons: photometric stability check, focus monitor,
pre-
and post-decon internals {bias, intflats, kspots, & darks}, UV
throughput
check, VISFLAT sweep, and internal UV flat check.
FLIGHT
OPERATIONS SUMMARY:
Significant
Spacecraft Anomalies: (The following are preliminary reports
of
potential non-nominal performance that will be investigated.)
HSTARS:
11350
- REacq(1,2,1) failed to RGA hold.
REacq(1,2,1) scheduled at 172/17:16:56 - 17:24:18 failed to RGA
hold
during LOS. At AOS there were no flags. During LOS we received an
ESB
a0a "FL Timeout". OBAD1 showed errors of V1=435.74,
V2=633.13,
V3=-307.65, and RSS=827.87. OBAD2 showed errors of V1=-0.75,
V2=-2.32,
V3=11.46, and RSS=11.71.
Observations affected: WFPC 152-155 Proposal ID# 11233
The REacq(1,2,1) scheduled at 172/18:52:49 - 19:00:00 also failed
during
LOS. There were no flags. OBAD1:V1=-365.74, V2=-546.47,V3=148.45,
RSS=674.11 OBAD2: V1=0.25, V2=0.89, V3=2.09, RSS=2.28
Observations affected: WFPC 156-159 Proposal ID# 11233
Reacq(1,2,1) scheduled at 172/20:28:42 also failed to RGA hold.
ESB
message a0a "FL Timeout" was received.
OBAD1: V1=-435.55, V2=-648.68, V3=189.11, RSS=803.90
OBAD2: V1=1.45, V2=4.26, V3=8.64, RSS=9.73
Observations affected: WFPC 160-162 Proposal ID#11233
Upon acquisition of signal at 172/22:39:30, the REacq(1,2,1)
scheduled
at 172/22:09:38 had failed to RGA Hold with (QF1SRLEX), (QF1STOPF)
indication flags set on FGS-1. One 486 ESB message "a07"
(FGS Coarse
Track failed - Timed out waiting for data valid FGS-1) was
received.
Pre-acq OBADs attitude corrections (RSS) values are not available
due to
LOS. Post-acq OBAD/MAP had not been scheduled.
Observations affected: WFPC 164, 165 Proposal ID#11233
COMPLETED
OPS REQUEST: (None)
COMPLETED
OPS NOTES: (None)
SCHEDULED
SUCCESSFUL
FGS
GSacq
17
17
FGS
REacq
10
06
OBAD
with Maneuver
54
54
SIGNIFICANT
EVENTS: (None)