HUBBLE
SPACE TELESCOPE - Continuing to collect World Class Science
DAILY
REPORT #4913
PERIOD
COVERED: 5am August 19 - 5am August 20, 2009 (DOY 231/09:00z-232/09:00z)
OBSERVATIONS
SCHEDULED
ACS/WFC3
11465
ACS
CCD Monitoring and Calibration for WFC3
This
program is a smaller version of our routine CCD monitoring program,
designed
to run throughout SMOV, after which our regular Cycle 17 CAL
proposal
will begin. This program obtains the bias and dark frames
needed
to generate reference files for calibrating science data, and
allows
us to monitor detector noise and the growth of hot pixels.
FGS
11874
Monitoring
FGS2R2 S-Curves after SMOV4
This
proposal satisfies the near-term requirement associated with SMOV4
activity
OTA/FGS-10, as well as the long term Cycle 17 requirement to
monitor
the post-SM4 evolution of the FGS2R2 S-curves stability during
its
first year on orbit. The S-curves will be obtained from Trans mode
observations
of stars (point sources) at several locations in the FGS2R2
FOV
in order to monitor both global and differential (i.e.,
field-dependent)
changes. At each location, both F583W and PUPIL
S-curves
will be obtained. Stars in the M35 cluster will be used for
this
proposal since the field lies very near the ecliptic and can
therefore
be observed by HST at two Orients from August to May.
STIS/CCD
11567
Boron
Abundances in Rapidly Rotating Early-B Stars
Models
of rotation in early-B stars predict that rotationally driven
mixing
should deplete surface boron abundances during the main-sequence
lifetime
of many stars. However, recent work has shown that many boron
depleted
stars are intrinsically slow rotators for which models predict
no
depletion should have occurred, while observations of nitrogen in
some
more rapidly rotating stars show less mixing than the models
predict.
Boron can provide unique information on the earliest stages of
mixing
in B stars, but previous surveys have been biased towards
narrow-lined
stars because of the difficulty in measuring boron
abundances
in rapidly rotating stars. The two targets observed as part of
our
Cycle 13 SNAP program 10175, just before STIS failed, demonstrate
that
it is possible to make useful boron abundance measurements for
early-B
stars with Vsin(i) above 100 km/s. We propose to extend that
survey
to a large enough sample of stars to allow statistically
significant
tests of models of rotational mixing in early-B stars.
STIS/CCD
11844
CCD
Dark Monitor Part 1
Monitor
the darks for the STIS CCD.
STIS/CCD
11846
CCD
Bias Monitor-Part 1
Monitor
the bias in the 1x1, 1x2, 2x1, and 2x2 bin settings at gain=1,
and
1x1 at gain = 4, to build up high-S/N superbiases and track the
evolution
of hot columns.
STIS/CCD
11852
STIS
CCD Spectroscopic Flats C17
Obtain
pixel-to-pixel lamp flat fields for the STIS CCD in spectroscopic
mode.
STIS/CCD/MA1/MA2
11690
EG
And: Providing the Missing Link Required for Modelling Red Giant
Mass-Loss
For
the majority of red giant stars the basic mass-loss processes at
work
are unknown. Indeed, for stars of spectral types between K0 III and
M5-M6
III, much remains unknown about the regions above the visible
photosphere
and the transportation of the processed material outwards to
the
ISM. Eclipsing symbiotic binary systems, consisting of an evolved
giant
in orbit with a white dwarf, provide an opportunity to take
advantage
of the finite size of the hot component to probe different
levels
of the chromosphere and wind acceleration region in absorption.
This
provides spatially resolved thermal, ionisation and dynamic
information
on the wind which can then be compared against predictions
of
hydrodynamical stellar atmosphere codes. The symbiotic binary EG And
can
be considered as a rosetta stone for understanding the winds of
these
objects. The system is ideal on a number of counts for utilising
the
ultraviolet eclipse of the white dwarf (WD) component to probe,
layer-by-layer,
the thermal and dynamic conditions at the very base of
the
wind and chromosphere of the RG. This information is vital for
constraining,
testing and calibrating the new generation of cool giant
wind+chromosphere
models and is not possible to obtain for isolated RGs.
This
team has studied the UV eclipses of this system in depth and
detail,
however in order to definitively constrain the wind acceleration
profile
and identify the location of the temperature rise just above the
photosphere
we require 4 STIS E140M observations of EG And at specific
orbital
phases. We are also requesting a E230M observation of an
isolated
spectral standard, corresponding to the RG in the binary, which
will
help place the EG And results into the context of the general RG
population
from analysis of the MgII wind diagnostic lines.
WFC3
11428
D2
Calibration Lamp Test
This
proposal verifies the health and performance of the calsystem
deuterium
lamp and assesses the status of the major UV filters by taking
a
full set of internal flatfields. A total of three nominal and one
short
exposure are obtained for each filter in order to establish an
initial
baseline of flatfield data as well as to confirm lamp
repeatability
and provide a contamination check. Additional iterations
of
D2 internal flatfields will be taken as part of WFC-19, UVIS Internal
Flats
(proposal 11432).
This
proposal corresponds to SMOV ID WFC3-15. It should not be run until
after
the successful completion of WFC-06, the UVIS detector functional
test
(proposal 11419) and WFC-11, the initial UVIS alignment (proposal
11424).
WFC3
11446
WFC3
UVIS Dark Current, Readnoise, and CTE
This
proposal obtains full-frame, four-amp readout bias and dark frames
at
regularly- spaced intervals throughout SMOV in order to assess and
monitor
dark current, bad (warm, hot, dead) pixels, and readnoise. In
addition,
a set of internals using the WFC3 calsystem are taken to
provide
a baseline CTE measurement. WFC3-33
WFC3/ACS/UVI
11360
Star
Formation in Nearby Galaxies
Star
formation is a fundamental astrophysical process; it controls
phenomena
ranging from the evolution of galaxies and nucleosynthesis to
the
origins of planetary systems and abodes for life. The WFC3,
optimized
at both UV and IR wavelengths and equipped with an extensive
array
of narrow-band filters, brings unique capabilities to this area of
study.
The WFC3 Scientific Oversight Committee (SOC) proposes an
integrated
program on star formation in the nearby universe which will
fully
exploit these new abilities. Our targets range from the
well-resolved
R136 in 30 Dor in the LMC (the nearest super star cluster)
and
M82 (the nearest starbursting galaxy) to about half a dozen other
nearby
galaxies that sample a wide range of star-formation rates and
environments.
Our program consists of broad band multiwavelength imaging
over
the entire range from the UV to the near-IR, aimed at studying the
ages
and metallicities of stellar populations, revealing young stars
that
are still hidden by dust at optical wavelengths, and showing the
integrated
properties of star clusters. Narrow-band imaging of the same
environments
will allow us to measure star-formation rates, gas
pressure,
chemical abundances, extinction, and shock morphologies. The
primary
scientific issues to be addressed are: (1) What triggers star
formation?
(2) How do the properties of star-forming regions vary among
different
types of galaxies and environments of different gas densities
and
compositions? (3) How do these different environments affect the
history
of star formation? (4) Is the stellar initial mass function
universal
or determined by local conditions?
WFC3/IR
11915
IR
Internal Flat Fields
This
program is the same as 11433 (SMOV) and depends on the completion
of
the IR initial alignment (program 11425). This version contains three
instances
of 37 internal orbits; to be scheduled early, middle, and near
the
end of Cycle 17, in order to use the entire 110-orbit allocation.
In
this test, we will study the stability and structure of the IR
channel
flat field images through all filter elements in the WFC3-IR
channel.
Flats will be monitored, i.e. to capture any temporal trends in
the
flat fields, and delta flats produced. High signal observations will
provide
a map of the pixel-to-pixel flat field structure, as well as
identify
the positions of any dust particles.
WFC3/IR
11937
IR
Grism Wavelength Calibration
This
program will determine the wavelength calibration for the IR G102
and
G141 grisms as a function of spatial position within the field of
view.
The planetary nebula Vy2-2 will be observed in a 9-point pattern
in
the IR field of view, which will provide FoV-dependent dispersion
maps
for the G102 and G141 grisms.
WFC3/UVI
11656
A
Comprehensive Survey of Neptune's Small Moons and Faint Rings
We
will use a subarray of the WFC3/UVIS to study the inner rings, arcs
and
moons of Neptune with a sensitivity that exceeds that achieved by
any
previous observations, including Voyager 2 during its 1989 flyby.
Our
study will reveal any inner moons down to V magnitude 25,
corresponding
to a radius ~ 20 km (assuming 9% albedo), to address a
peculiar,
apparent truncation in the size distribution of inner moons
and
to look for the "shepherds" and source bodies for Neptune's dusty
rings.
(For comparison, the radius of Neptune's smallest known regular
moon,
Naiad, is ~ 33 km.) Monitoring of the arcs at fine resolution and
sensitivity
will reveal their ongoing evolution more clearly and will
enable
us to assess the role of Galatea, whose resonant perturbations
are
widely believed to confine the arcs. Our study will also reveal any
broad,
faint rings with optical depth ~ 10^-6, comparable to those now
known
to encircle all of the other giant planets.
WFC3/UVI
11905
WFC3
UVIS CCD Daily Monitor
The
behavior of the WFC3 UVIS CCD will be monitored daily with a set of
full-frame,
four-amp bias and dark frames. A smaller set of 2Kx4K
subarray
biases are acquired at less frequent intervals throughout the
cycle
to support subarray science observations. The internals from this
proposal,
along with those from the anneal procedure (11909), will be
used
to generate the necessary superbias and superdark reference files
for
the calibration pipeline (CDBS).
WFC3/UVI
11908
Cycle
17: UVIS Bowtie Monitor
Ground
testing revealed an intermittent hysteresis type effect in the
UVIS
detector (both CCDs) at the level of ~1%, lasting hours to days.
Initially
found via an unexpected bowtie-shaped feature in flatfield
ratios,
subsequent lab tests on similar e2v devices have since shown
that
it is also present as simply an overall offset across the entire
CCD,
i.e., a QE offset without any discernable pattern. These lab tests
have
further revealed that overexposing the detector to count levels
several
times full well fills the traps and effectively neutralizes the
bowtie.
Each visit in this proposal acquires a set of three 3x3 binned
internal
flatfields: the first unsaturated image will be used to detect
any
bowtie, the second, highly-exposed image will neutralize the bowtie
if
it is present, and the final image will allow for verification that
the
bowtie is gone.
FLIGHT
OPERATIONS SUMMARY:
Significant
Spacecraft Anomalies: (The following are preliminary reports
of
potential non-nominal performance that will be investigated.)
HSTARS:
11985
- GSAcq(1,2,1) scheduled at 231/08:19:50 - 08:27:01 had resulted
in fine lock backup (2,0,2) using FGS-2 due to (QF1STOPF) stop
flag
indication on FGS-1.
Observations possibly affected, STIS 42 Proposal ID# 11567.
COMPLETED
OPS REQUEST: (None)
COMPLETED
OPS NOTES: (None)
SCHEDULED
SUCCESSFUL
FGS
GSAcq
7
7
FGS
REAcq
8
8
OBAD
with Maneuver
8
8
SIGNIFICANT
EVENTS: (None)