HUBBLE
SPACE TELESCOPE - Continuing to collect World Class Science
DAILY
REPORT # 4561
PERIOD
COVERED: UT March 05, 2008 (DOY 065)
OBSERVATIONS
SCHEDULED
FGS
11210
The
Architecture of Exoplanetary Systems
Are
all planetary systems coplanar? Concordance cosmogony makes that
prediction.
It is, however, a prediction of extrasolar planetary system
architecture
as yet untested by direct observation for main sequence
stars
other than the Sun. To provide such a test, we propose to carry
out
FGS astrometric studies on four stars hosting seven companions. Our
understanding
of the planet formation process will grow as we match not
only
system architecture, but formed planet mass and true distance from
the
primary with host star characteristics for a wide variety of host
stars
and exoplanet masses. We propose that a series of FGS astrometric
observations
with demonstrated 1 millisecond of arc per-observation
precision
can establish the degree of coplanarity and component true
masses
for four extrasolar systems: HD 202206 {brown dwarf+planet}; HD
128311
{planet+planet}, HD 160691 = mu Arae {planet+planet}, and HD
222404AB
= gamma Cephei {planet+star}. In each case the companion is
identified
as such by assuming that the minimum mass is the actual mass.
For
the last target, a known stellar binary system, the companion orbit
is
stable only if coplanar with the AB binary orbit.
NIC1/NIC2/NIC3
11330
NICMOS
Cycle 16 Extended Dark
This
takes a series of Darks in parallel to other instruments.
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.
NIC3
11153
The
Physical Nature and Age of Lyman Alpha Galaxies
In
the simplest scenario, strong Lyman alpha emission from high redshift
galaxies
would indicate that stellar populations younger than 10 Myrs
dominate
the UV. This does not, however, constrain the stellar
populations
older than 100 Myrs, which do not contribute to UV light.
Also,
the Lyman alpha line can be boosted if the interstellar medium is
both
clumpy and dusty. Different studies with small samples have reached
different
conclusions about the presence of dust and old stellar
populations
in Lyman alpha emitters. We propose HST- NICMOS and
Spitzer-IRAC
photometry of 35 Lyman-alpha galaxies at redshift
4.5<z<6.5,
in order to determine their spectral energy distribution
{SED}
extending through rest-frame optical. This will allow us to
measure
accurately {1} The total stellar mass in these objects,
including
old stars which may have formed at redshifts {z > 8} not
easily
probed by any other means. {2} The dust extinction in the
rest-frame
UV, and therefore a correction to their present
star-formation
rates. Taken together, these two quantities will yield
the
star-formation histories of Lyman alpha galaxies, which form fully
half
of the known galaxies at z=4-6. They will tell us whether these are
young
or old galaxies by straddling the 4000A break. Data from NICMOS is
essential
for these compact and faint {i=25-26th magnitude AB} high
redshift
galaxies, which are too faint for good near-IR photometry from
the
ground.
NIC3
11334
NICMOS
Cycle 16 Spectrophotometry
Observation
of the three primary WD flux standards must be repeated to
refine
the NICMOS absolute calibration and monitor for sensitivity
degradation.
So far, NICMOS grism spectrophotometry is available for
only
~16 stars with good STIS spectra at shorter wavelengths. There are
more
in the HST CALSPEC standard star data base with good STIS spectra
that
would also become precise IR standards with NICMOS absolute SED
measurements.
Monitoring the crucial three very red stars (M, L, T) for
variability
and better S/N in the IR. Apparent variability was
discovered
at shorter wavelengths during the ACS cross-calibration work
that
revealed a ~2% discrepancy of the cool star fluxes with respect to
the
hot primary WD standards. About a third of these stars are bright
enough
to do in one orbit, the rest require 2 orbits.
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
11122
Expanding
PNe: Distances and Hydro Models
We
propose to obtain repeat narrowband images of a sample of eighteen
planetary
nebulae {PNe} which have HST/WFPC2 archival data spanning time
baselines
of a decade. All of these targets have previous high
signal-to-noise
WFPC2/PC observations and are sufficiently nearby to
have
readily detectable expansion signatures after a few years. Our main
scientific
objectives are {a} to determine precise distances to these
PNe
based on their angular expansions, {b} to test detailed and highly
successful
hydrodynamic models that predict nebular morphologies and
expansions
for subsamples of round/elliptical and axisymmetric PNe, and
{c}
to monitor the proper motions of nebular microstructures in an
effort
to learn more about their physical nature and formation
mechanisms.
The proposed observations will result in high-precision
distances
to a healthy subsample of PNe, and from this their expansion
ages,
luminosities, CSPN properties, and masses of their ionized cores.
With
good distances and our hydro models, we will be able to determine
fundamental
parameters {such as nebular and central star masses,
luminosity,
age}. The same images allow us to monitor the changing
overall
ionization state and to search for the surprisingly
non-homologous
growth patterns to bright elliptical PNe of the same sort
seen
by Balick & Hajian {2004} in NGC 6543. Non-uniform growth is a sure
sign
of active pressure imbalances within the nebula that require
careful
hydro models to understand.
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
11146
The
Role of Stellar Feedback in Galaxy Evolution
Stellar
feedback - the return of mass and energy from star formation to
the
interstellar medium - is one of the primary engines of galaxy
evolution.
Yet, the observational canvass of feedback is incomplete. We
propose
to investigate this fundamental aspect of star formation on one
local
actively star-forming galaxy, He2-10, selected to occupy an
unexplored
niche in the key parameter space of stellar mass. The WFPC2
narrow-band
observations in the light of H-beta, [OIII], H-alpha, and
[SII]
will: {1} discriminate the feedback-induced shock fronts from the
photoionized
regions; {2} map, and provide a complete census of, the
shocks
inside and around the starburst regions; and {3} measure the
energy
budget of the star-formation-produced shocks. These observations,
joined
by our previous data and studies on starbursts, will yield: {1}
the
efficiency of the feedback, i.e. the fraction of the star
formation's
mechanical energy transported out of the starburst volume
rather
than radiated away, in the dual-parameter space of host's stellar
mass
and star formation intensity; {2} the conditions under which
feedback
morphs from a localized process to a galactic scale mechanism.
The
high angular resolution of HST is crucial for separating the
spatially
narrow shock fronts {~10 pc=0.2" at 10 Mpc} from the more
extended
photoionization fronts. This project will provide the most
comprehensive
quantitative foundation of stellar feedback and a gauge
for
determining the role of feedback in the energetics, structure and
star
formation history of galaxies.
WFPC2
11198
Pure
Parallel Imaging in the NDWFS Bootes Field
The
NOAO Deep-Wide Field Survey {NDWFS} Bootes field is the target of
one
of the most extensive multiwavelength campaigns in astronomy. In
addition
to ground-based optical and near-infrared imaging, deep radio
mapping,
and extensive spectroscopy, this entire region has been imaged
by
the Chandra, Spitzer {IRAC and MIPS}, and GALEX missions. Robust
photometric
redshifts {calibrated using over 20,000 spectroscopic
redshifts}
exist for all sources brighter than R=24.5 or than 13 uJy at
4.5
microns. To enhance the value of this data set, we propose pure
parallel
observations for all approved Cycle 16 programs in this region
that
lack coordinated parallel observations. The primary aim of this
program
will be to provide a database useful for the broad range of
science
programs underway in this region.
WFPC2
11297
Reducing
Systematic Errors on the Hubble Constant: Metallicity
Calibration
of the
Reducing
the systematic errors on the Hubble constant is still of
significance
and of immediate importance to modern cosmology. One of the
largest
remaining uncertainties in the Cepheid-based distance scale
(which
itself is at the foundation of the HST Key Project determination
of
H_o) which can now be addressed directly by HST, is the effect of
metallicity
on the Cepheid Period-Luminosity relation. Three chemically
distinct
regions in M101 will be used to directly measure and thereby
calibrate
the change in zero point of the
range
of metallicities that run from SMC-like, through Solar, to
metallicities
as high as the most metal-enriched galaxies in the pure
Hubble
flow. ACS for the first time offers the opportunity to make a
precise
calibration of this effect which currently accounts for at least
a
third of the total systematic uncertainty on Ho. The calibration will
be
made in the V and I bandpasses so as to be immediately and directly
applicable
to the entire HST Cepheid-based distance scale sample, and
most
especially to the highest-metallicity galaxies that were hosts to
the
Type Ia supernovae, which were then used to extend the the distance
scale
calibration out to cosmologically significant distances.
FLIGHT
OPERATIONS SUMMARY:
Significant
Spacecraft Anomalies: (The following are preliminary reports
of
potential non-nominal performance that will be investigated.)
HSTARS:
None
COMPLETED
OPS REQUEST:
17597-9
- FHST Stuck-on-Bottom Macro Execution
COMPLETED
OPS NOTES: (None)
SCHEDULED
SUCCESSFUL
FGS
GSacq
07
07
FGS
REacq
07
07
OBAD
with Maneuver
28
28
SIGNIFICANT
EVENTS: (None)