Notice: Due to the conversion of some ACS WFC or HRC
observations into
WFPC2, or NICMOS observations after the loss of ACS CCD
science
capability in January, there may be an occasional
discrepancy between a
proposal's listed (and correct) instrument usage and the
abstract that
follows it.
HUBBLE SPACE TELESCOPE - Continuing to collect World Class
Science
DAILY REPORT # 4427
PERIOD COVERED: UT August 15, 2007 (DOY 227)
OBSERVATIONS SCHEDULED
ACS/SBC 10840
The FUV fluxes of Tauri stars in the Taurus molecular
cloud
Present and forthcoming ground-based and space surveys of
the T Tauri
stars in the Taurus molecular cloud will provide
information from high
energy stellar and accretion radiation to low energy solid
state and
molecular emission from the disk, making those stars
perfect
laboratories to carry out self-consistent studies of disk
physics and
evolution. We propose to complete this wealth of
information by
obtaining ACS/FUV spectra for a significant sample of
Taurus T Tauri
stars, covering a range of accretion properties and dust
evolutionary
stages. FUV fluxes carry ~ 10 - 100 more energy than
X-rays into these
disks and are thus crucial gas heating agents and key to
disk dispersal
by photoevaporation. These observations are a
pre-requisite to interpret
observations with Spitzer, SOFIA, Herschel, and ALMA, and
will become
one of the important legacies of HST to the star formation
community.
NIC1 11063
NICMOS Focus Monitoring
This program is a version of the standard focus sweep used
since cycle
7. It has been modified to go deeper and uses more narrow
filters for
improved focus determination. For Cycle14 a new source has
been added in
order to accommodate 2-gyro mode: the open cluster
NGC1850. The old
target, the open cluster NGC3603, will be used whenever
available and
the new target used to fill the periods when NGC3603 is
not visible.
Steps: a} Use refined target field positions as determined
from cycle 7
calibrations b} Use MULTIACCUM sequences of sufficient
dynamic range to
account for defocus c} Do a 17- point focus sweep, +/- 8mm
about the PAM
mechanical zeropoint for each cameras 1 and 2, in 1.0mm
steps. d} Use
PAM X/Y tilt and OTA offset slew compensations refined
from previous
focus monitoring/optical alignment activities
NIC1/NIC2/NIC3 8794
NICMOS Post-SAA calibration - CR Persistence Part 5
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 DARKs. 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
images. Each observation will need its own CRMAP, as
different SAA
passages leave different imprints on the NICMOS detectors.
NIC2 11133
Late-Time Photometry of SN 2005hk: A New Kind of Type Ia
Supernova
Our lack of understanding of Type Ia
supernova {SN Ia} explosions limits
our confidence in their use for cosmology. While there is
broad
agreement that these objects represent the explosions of
white dwarfs,
the details of the explosion mechanism are not well-
understood. Recent
observations have detected a previously unacknowledged
variant class of
SNe Ia whose photometric and
spectroscopic peculiarities make them quite
distinct from normal SNe
Ia. These objects represent a
challenge for
thermonuclear supernova models, as a complete theory of
exploding white
dwarfs must allow for their existence. A particularly
well-studied
example of this class of objects is the recent SN 2005hk,
whose
properties in some respects resemble those of models which
invoke a
subsonic burning front, called a deflagration. We propose
to test SN Ia
models by obtaining late-time photometry for this extreme
SN Ia using
WFPC2 and NICMOS on HST. We will accurately measure the
late-time
photometric decline rate and spectral energy distribution
{SED}. These
observations will allow us to test whether the ejecta
contain the large
amount of oxygen predicted by certain models, the
efficiency of energy
deposition by gamma rays and positrons, and possibly
detect major
evolution of the SED expected due to a change in the
dominant cooling
mechanism of the ejecta.
NIC2 11219
Active Galactic Nuclei in nearby galaxies: a new view of
the origin of
the radio-loud radio- quiet dichotomy?
Using archival HST and Chandra observations of 34 nearby
early-type
galaxies {drawn from a complete radio selected sample} we
have found
evidence that the radio-loud/radio-quiet dichotomy is
directly connected
to the structure of the inner regions of their host
galaxies in the
following sense: [1] Radio-loud AGN are associated with
galaxies with
shallow cores in their light profiles [2] Radio-quiet AGN
are only
hosted by galaxies with steep cusps. Since the brightness
profile is
determined by the galaxy's evolution, through its merger
history, our
results suggest that the same process sets the AGN
flavour. This
provides us with a novel tool to explore the co-evolution
of galaxies
and supermassive black holes, and it opens a new path to
understand the
origin of the radio-loud/radio-quiet AGN dichotomy.
Currently our
analysis is statistically incomplete as the brightness
profile is not
available for 82 of the 116 targets. Most galaxies were
not observed
with HST, while in some cases the study is obstructed by
the presence of
dust features. We here propose to perform an infrared
NICMOS snapshot
survey of these 82 galaxies. This will enable us to i}
test the reality
of the dichotomic behaviour in a substantially larger
sample; ii} extend
the comparison between radio-loud and radio-quiet AGN to a
larger range
of luminosities.
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
10
10
FGS REacq
04
04
OBAD with Maneuver
28
28
SIGNIFICANT EVENTS: (None)