HUBBLE SPACE TELESCOPE - Continuing to collect World Class
Science
DAILY REPORT #4670
PERIOD COVERED: 5am August 7 - 5am August 8, 2008 (DOY
220/0900z-221/0900z)
OBSERVATIONS SCHEDULED
FGS 11212
Filling the Period Gap for Massive Binaries
The current census of binaries among the massive O-type
stars is
seriously incomplete for systems in the period range from
years to
millennia because the radial velocity variations are too
small and the
angular separations too close for easy detection. Here we
propose to
discover binaries in this observational gap through a
Faint Guidance
Sensor SNAP survey of relatively bright targets listed in
the Galactic O
Star Catalog. Our primary goal is to determine the binary
frequency
among those in the cluster/association, field, and runaway
groups. The
results will help us assess the role of binaries in
massive star
formation and in the processes that lead to the ejection
of massive
stars from their natal clusters. The program will also
lead to the
identification of new, close binaries that will be targets
of long term
spectroscopic and high angular resolution observations to
determine
their masses and distances. The results will also be
important for the
interpretation of the spectra of suspected and newly
identified binary
and multiple systems.
NIC1 11136
Resolving Ultracool Astrophysics with Brown Dwarf Binaries
We propose to obtain resolved far-red and near-IR
photometry of 13 brown
dwarf binaries with HST/NICMOS in order to study one of
the
long-standing puzzles in ultracool astrophysics, namely
the rapid change
in spectra from L dwarfs to T dwarfs at nearly constant
effective
temperature (a.k.a. the "L/T transition''). While
many nearby brown
dwarfs have been studied, use of such samples is
inevitably hindered by
the unknown ages, masses, and metallicities of the field
population.
Characterization of resolved ultracool binaries is a
promising avenue
for addressing this problem, by providing coeval systems
of the same
composition with comparable masses and temperatures. Our
proposed
HST/NICMOS (0.9-1.6 micron) observations will be combined
with longer
wavelength ground-based photometry and spectroscopy from
Keck laser
guide star adaptive optics. The resulting multiband
(0.9-2.5 micron)
dataset will be a unique resource for measuring the
evolution of
spectral energy distributions across the L/T transition,
to test
state-of-the-art atmospheric models, and to determine the
physical
process(es) that dominate the L/T transition.
Understanding the L/T
transition is important not only for testing brown dwarf
atmospheres,
but also provides a key pathway for understanding the same
physical
effects, namely the formation and removal of clouds, in the
atmospheres
of the extrasolar planets.
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.
NIC2 11164
Molecular Hydrogen Disks Around T Tauri Stars
We propose to measure the properties of planetary
system-sized disks
around Sun- like, pre-main sequence stars by imaging the
inner parts of
these disks for the first time in gaseous emission from their
most
dominant constituent, molecular hydrogen gas. Specifically,
we will use
the F212N filter and NICMOS to determine the spatial
distribution of
ro-vibrational H2 emission from protoplanetary disks
around selected
classical and weak-lined T Tauri stars. The target stars
are among those
detected by members of this team through high resolution,
ground-based
infrared spectroscopy. The spectra reveal H2 emission at
the rest
velocities of the stars and at positions spatially
coincident with the
stars at the spatial resolution of the spectroscopic data.
This imaging
experiment, which is impossible to do using ground- based
facilities, is
possible using the NICMOS camera aboard the HST because
the point spread
function of this system is extremely stable and can be
measured to a
very high accuracy. This experiment is an important test
of the
interpretation that the 2.122 micron H2 line emission seen
toward T
Tauri stars is produced at distances of 10 to 30 AU from
the stars, the
region in which giant planets are expected to form around
these stars.
These observations will contribute toward developing a
better
understanding of the process, likelihood, and timescale
for the
formation of planets around Sun-like stars.
NIC2/WFPC2 11142
Revealing the Physical Nature of Infrared Luminous
Galaxies at 0.3<z<2.7
Using HST and Spitzer
We aim to determine physical properties of IR luminous
galaxies at
0.3<z<2.7 by requesting coordinated HST/NIC2 and
MIPS 70um observations
of a unique, 24um flux-limited sample with complete
Spitzer mid-IR
spectroscopy. The 150 sources investigated in this program
have S{24um}
> 0.8mJy and their mid-IR spectra have already provided
the majority
targets with spectroscopic redshifts {0.3<z<2.7}.
The proposed
150~orbits of NIC2 and 66~hours of MIPS 70um will provide
the physical
measurements of the light distribution at the rest-frame
~8000A and
better estimates of the bolometric luminosity. Combining
these
parameters together with the rich suite of spectral
diagnostics from the
mid-IR spectra, we will {1} measure how common mergers are
among LIRGs
and ULIRGs at 0.3<z<2.7, and establish if major
mergers are the drivers
of z>1 ULIRGs, as in the local Universe. {2} study the
co-evolution of
star formation and blackhole accretion by investigating
the relations
between the fraction of starburst/AGN measured from mid-IR
spectra vs.
HST morphologies, L{bol} and z. {3} obtain the current
best estimates of
the far-IR emission, thus L{bol} for this sample, and
establish if the
relative contribution of mid-to-far IR dust emission is
correlated with
morphology {resolved vs. unresolved}.
NIC3 11072
Measuring the Physical Properties of the First Two WASP
Transiting
Extrasolar planets
We have recently discovered the first two transiting extrasolar
planets
from the Wide Angle Search for Planets {WASP} project and
confirmed both
as planets using SOPHIE radial velocity measurements. Both
WASP-1b and
WASP-2b orbit about stars brighter than V=12, and are thus
ideal targets
for HST followup. WASP-1b is probably inflated in a manner
similar to
HD209458b but is in a closer orbit about the parent, which
itself is the
earliest-type parent star yet announced for a transiting
extrasolar
planet. At 0.03 AU from the parent star, WASP-2b is close
to the minimum
separation at which planets of this mass range are thought
to survive.
We request DD observations of WASP-1b and WASP-2b, to
constrain the
masses and radii of both objects to a precision of a few
tenths of a
percent. Both parent stars have very similar brightnesses
to the TrES-1
parent star, thus we will achieve equivalent photometric
precision to
previous successful observations of TrES-1b. As all
further physical
investigations {such as interior heating} depend on
precise mass- and
radius-determinations, this investigation is the essential
next step in
uncovering the physical characteristics of these planets
and their
parent stars. We have requested 12 orbits, though 9 orbits
would provide
the minimum acceptable coverage for our program. The
consortium will
formally announce the discoveries of WASP-1b and WASP-2b
on Tuesday 26th
September 2006. We ask that all material in this proposal
be kept
confidential until that date. We can supply the discovery
paper on
request after this date.
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!
WFPC2 11796
WFPC2 Cycle 16 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.
WFPC2 11804
WFPC2 Closeout Calibration -- CTE Effects on Standard Star
Observations of the primary standard star GRW+70D5824 are
made at
several different places on the CCD to directly estimate
the impact of
CTE. All four CCDs are evaluated. Filters F170W and F555W
are used to
evaluate the effects of background and different PSF
shapes / sizes.
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: (None)
COMPLETED OPS NOTES: (None)
SCHEDULED
SUCCESSFUL
FGS GSacq
07
07
FGS REacq
08
08
OBAD with Maneuver
30
30
SIGNIFICANT EVENTS: (None)