HUBBLE
SPACE TELESCOPE - Continuing to collect World Class Science
DAILY
REPORT # 4629
PERIOD
COVERED: 5am June 10 - 5am June 11, 2008 (DOY 162/0900z-163/0900z)
OBSERVATIONS
SCHEDULED
NIC1/NIC2
11155
Dust
Grain Evolution in Herbig Ae Stars: NICMOS Coronagraphic Imaging
and
Polarimetry
We
propose to take advantage of the sensitive coronagraphic capabilities
of
NICMOS to obtain multiwavelength coronagraphic imaging and
polarimetry
of primordial dust disks around young intermediate-mass
stars
{Herbig Ae stars}, in order to advance our understanding of how
dust
grains are assembled into larger bodies. Because the polarization
of
scattered light is strongly dependent on scattering particle size and
composition,
coronagraphic imaging polarimetry with NICMOS provides a
uniquely
powerful tool for measuring grain properties in spatially
resolved
circumstellar disks. It is widely believed that planets form
via
the gradual accretion of planetesimals in gas-rich, dusty
circumstellar
disks, but the connection between this suspected process
and
the circumstellar disks that we can now observe around other stars
remains
very uncertain. Our proposed observations, together with
powerful
3-D radiative transfer codes, will enable us to quantitatively
determine
dust grain properties as a function of location within disks,
and
thus to test whether dust grains around young stars are in fact
growing
in size during the putative planet-formation epoch. HST imaging
polarimetry
of Herbig Ae stars will complement and extend existing
polarimetric
studies of disks around lower-mass T Tauri stars and debris
disks
around older main-sequence stars. When combined with these
previous
studies, the proposed research will help us establish the
influence
of stellar mass on the growth of dust grains into larger
planetesimals,
and ultimately to planets. Our results will also let us
calibrate
models of the thermal emission from these disks, a critical
need
for validating the properties of more distant disks inferred on the
basis
of spectral information alone.
NIC1/NIC2/NIC3
11318
NICMOS
Cycle 16 Multiaccum Darks
The
purpose of this proposal is to monitor the dark current, read noise,
and
shading profile for all three NICMOS detectors throughout the
duration
of Cycle 16. This proposal is a slightly modified version of
proposal
10380 of cycle 13 and 9993 of cycle12 and is the same as Cycle
15.
Covers the period from April 08 to November 08 (inclusive)
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/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}.
WFPC2
11129
The
Star Formation History of the Fornax Dwarf Spheroidal Galaxy
The
Fornax dwarf spheroidal galaxy is one of the most luminous dwarf
satellites
of the Milky Way. It is unusual in many ways: it hosts 5
globular
clusters, shows some relatively young stars, and has faint
sub-structures
which have been interpreted as signs of recent
interactions.
It is thus of great interest to learn the complete star
formation
history {SFH} of Fornax to establish a link between its
evolutionary
path and the predictions from numerical simulations, as a
test
of our understanding of dwarf galaxy evolution. Yet many questions
remain
open. Is the old stellar population made up of stars formed in a
very
early burst, perhaps before the epoch of re-ionization, or the
result
of a more continuous star formation between 13 and 9 Gyr ago ?
How
quickly did Fornax increase its metallicity during its initial
assembly
and during subsequent episodes of star formation ? Are
accretion
episodes required to explain the age-metallicity history of
Fornax
? However, there has never been a comprehensive study of the
global
SFH of the Fornax field based on data of sufficient depth to
unambiguously
measure the age mixture of the stellar populations and
their
spatial variation. We propose to use the WFPC2 to obtain very deep
images
in several fields across the central region of Fornax in order to
reach
the oldest main-sequence turnoffs. The number of fields is
determined
by the need to measure the SFH over different regions with
distinct
kinematics and metallicity. The resolution achievable with HST
is
crucial to answer these questions because, to derive the age
distribution
of the oldest stars, we are interested in I magnitude
differences
of the order 0.2 mag in crowded fields at V=24.5. We will
directly
measure the time variation in star-formation rate over the
entire
galaxy history, from first stars coeval with the Milky Way halo
to
the youngest populations 200 Myr ago. The combination of detailed CMD
analysis
with WFPC2 with our existing metallicity and kinematic
information
will allow us to trace out the early phases of its
evolution.
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
11340
X-ray
Observations of 11 Millisecond Pulsars in M28
We
propose a deep X-ray survey of the globular cluster M28 which will
yield
a wealth of important and unique science, ranging from the first
direct
measurement of the magnetic field of a millisecond pulsar and
constraints
on the neutron star equation of state to likely
X-ray/optical
(HST) detection of a re-exchanged binary MSP. The proposed
joint
HST WFPC2 observation will tie the X-ray, optical, and radio data
to
a common astrometric frame allowing an unambiguous identification of
numerous
cataclysmic variables and active binaries in M28 as well as
making
possible the first direct optical detection of a millisecond
pulsar.
FLIGHT
OPERATIONS SUMMARY:
Significant
Spacecraft Anomalies: (The following are preliminary reports
of
potential non-nominal performance that will be investigated.)
HSTARS:
11334
- REAcq(2,1,2) failed to RGA Hold (Gyro Control)
Upon acquisition of signal at 162/12:34:30, REAcq(2,1,2) scheduled
at
162/12:30:52 - 12:38:57 was observed to have failed to RGA Hold
due to
stop flag (QF2STOPF) on FGS-2. Pre-acq OBAD1 attitude correction
(RSS)
value was not available due to LOS. OBAD2 had (RSS) value of 5.48
arcseconds. Post-acq OBAD/MAP had (RSS) value of 13.10 arcseconds.
Prior
GSAcq(2,1,2) at 162/10:55:26 was successful.
Possible Observations Affected: WFPCII 87 thru 91, Proposal #
11340.
NICMOS 19, 20, Proposal # 11318
At AOS 162/14:17:45, subsequent REAcq(2,1,2) at 162/14:06:46 also
failed
to RGA Hold due to stop flag on FGS-2.
Observations Affected: WFPC 92 thru 96 Proposal # 11340. NICMOS
24, 25
Proposal # 11318
11335
- NICMOS Status Buffer Message
Parameter=1, Time= 4274; NIC in Operate mode; next obs at
163/05:28:10z.#668 indicates MECH_UNSTABLE_INDUCTOSYN Description:
"While verifying the mechanical position following a
mechanism movement,
consecutive position calculations give inconsistent values. This
indicates the inductosyn coarse and fine positions are changing.
"FSW
Action: Status Buffer Message ERROR Parameter indicates: Mechanism
no.
(FW1=0, FW2=1, FW3=2, FOMX=3, FOMY=4). Ground Action: None.
Obs might be affected: NIC #26-28 of Proposal #11155.
Ops Request 18241-0, to reset the NICMOS error counter, was
successfully executed at 162/19:35:45.
COMPLETED
OPS REQUEST:
18241-0
- Execute ROP NS-11 Reset NICMOS Error Counter @ 162/1935z
COMPLETED
OPS NOTES: (None)
SCHEDULED
SUCCESSFUL
FGS
GSacq
06
06
FGS
REacq
08
06
OBAD
with Maneuver
28
27
SIGNIFICANT
EVENTS: (None)