HUBBLE
SPACE TELESCOPE - Continuing to collect World Class Science
DAILY
REPORT # 4599
PERIOD
COVERED: UT April 28, 2008 (DOY 119)
OBSERVATIONS
SCHEDULED
SIGNIFICANT
EVENTS: (None)
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.
FGS
11214
HST/FGS
Astrometric Search for Young Planets Around Beta Pic and AU Mic
Beta
Pic and AU Mic are two nearby Vega-type debris disk stars. Both of
these
disk systems have been spatially resolved in exquisite detail,
predominantly
via the ACS coronagraph and WFPC-2 cameras onboard HST.
These
images exhibit a wealth of morphological features which provide
compelling
indirect evidence that these systems likely harbor
short-period
planetary body{ies}. We propose to use the superlative
astrometric
capabilities of HST/FGS to directly detect these planets,
hence
provide the first direct planet detection in a Vega-type system
whose
disk has been imaged at high spatial resolution.
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
11120
A
Paschen-Alpha Study of Massive Stars and the ISM in the Galactic
Center
The
Galactic center (GC) is a unique site for a detailed study of a
multitude
of complex astrophysical phenomena, which may be common to
nuclear
regions of many galaxies. Observable at resolutions
unapproachable
in other galaxies, the GC provides an unparalleled
opportunity
to improve our understanding of the interrelationships of
massive
stars, young stellar clusters, warm and hot ionized gases,
molecular
clouds, large scale magnetic fields, and black holes. We
propose
the first large-scale hydrogen Paschen alpha line survey of the
GC
using NICMOS on the Hubble Space Telescope. This survey will lead to
a
high resolution and high sensitivity map of the Paschen alpha line
emission
in addition to a map of foreground extinction, made by
comparing
Paschen alpha to radio emission. This survey of the inner 75
pc
of the Galaxy will provide an unprecedented and complete search for
sites
of massive star formation. In particular, we will be able to (1)
uncover
the distribution of young massive stars in this region, (2)
locate
the surfaces of adjacent molecular clouds, (3) determine
important
physical parameters of the ionized gas, (4) identify compact
and
ultra-compact HII regions throughout the GC. When combined with
existing
Chandra and Spitzer surveys as well as a wealth of other
multi-wavelength
observations, the results will allow us to address such
questions
as where and how massive stars form, how stellar clusters are
disrupted,
how massive stars shape and heat the surrounding medium, and
how
various phases of this medium are interspersed.
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.
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
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
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!
FLIGHT
OPERATIONS SUMMARY:
Significant
Spacecraft Anomalies: (The following are preliminary reports
of
potential non-nominal performance that will be investigated.)
HSTARS:
11282
- GSAcq(1,2,1) Loss of Lock while guiding
Following a successful GSAcq (1,2,1), scheduled at 120/07:18:21, a
Loss
of Lock occurred while guiding under FGS 1 and 2 at 120/07:38:40.
(QF1STOPF) stop flag indication set on FGS-1. P4TAKDAT (Take Data
Flag)
went down at that time, causing ACS 779 Status Buffer Messages
("Fold
Mechanism Move Was Blocked") to occur at 120/07:38:40,
120/07:50:13,
120/08:01:46. The spacecraft entered T2G mode. The TERM EXP was
not
scheduled until 120/08:15:52.
COMPLETED
OPS REQUEST: (None)
COMPLETED
OPS NOTES: (None)
SCHEDULED
SUCCESSFUL FAILURE TIMES
FGS
GSacq
10
10
FGS
REacq
04
04
OBAD
with Maneuver
28
28
LOSS
of LOCK
120/07:38:40z
SIGNIFICANT
EVENTS: (None)