Daily #3979
- From: Joe Cooper <jcooper@xxxxxxxxxxxx>
- Date: Tue, 8 Nov 2005 15:39:42 +0000 (UTC)
HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science
DAILY REPORT # 3979
PERIOD COVERED: UT November 01, 2005 (DOY 305)
OBSERVATIONS SCHEDULED
ACS/HRC 10539
Coronagraphic Imaging of Bright New Spitzer Debris Disks
Fifteen percent of bright main sequence stars possess dusty
circumstellar debris disks revealed by far-infrared photometry. These
disks are signposts of planetary systems: collisions among larger,
unseen parent bodies maintain the observed dust population against
losses to radiation pressure and P-R drag. Images of debris disks at
optical, infrared, and millimeter wavelengths have shown central holes,
rings, radial gaps, warps, and azimuthal asymmetries which indicate the
presence of planetary mass perturbers. Such images provide unique
insights into the structure and dynamics of exoplanetary systems.
Relatively few debris disks have been spatially resolved. Only nine have
ever been resolved at any wavelength, and at wavelengths < 10 microns
{where subarcsec resolution is available}, only seven: beta Pictoris, HR
4796, HD 141569, AU Mic, HD 107146, HD 92945, and Fomalhaut. Imaging of
many other debris disk targets has been attempted with various HST
cameras/coronagraphs and adaptive optics, but without success. The key
property which renders a debris disk observable in scattered light is
its dust optical depth. The seven disks imaged so far all have a dust
excess luminosity >~ 0.01% that of the central star; no disks with
smaller optical depths have been detected. Most main sequence stars
known to meet this requirement have already been observed, so future
progress in debris disk imaging depends on discovering additional stars
with large infrared excess. The Spitzer Space Telescope offers the best
opportunity in 20 years to identify new examples of high optical depth
debris disk systems. We propose ACS coronagraphic imaging of nine
bright, new debris disks uncovered during the first year of the Spitzer
mission. Our goal is to obtain the first resolved images of these disks
at ~3 AU resolution, define the disk sizes and orientations, and uncover
disk substructures indicative of planetary perturbations. The results
should double the number of debris disks observed at 0.06" resolution,
and open a wider window into the structure of planetary systems.
ACS/WFC 10491
A Snapshot Survey of the most massive clusters of galaxies
We propose a snapshot survey of a sample of 124 high X-ray luminosity
clusters in the redshift range 0.3-0.7. Similarly luminous clusters at
these redshifts frequently exhibit strong gravitational lensing. The
proposed observations will provide important constraints on the nature
of the cluster mass distributions and a set of optically bright, lensed
galaxies for further 8-10m spectroscopy. We acknowledge the broad
community interest in this sample and waive our data rights for these
observations.
ACS/WFC 10496
Decelerating and Dustfree: Efficient Dark Energy Studies with Supernovae
and Clusters
We propose a novel HST approach to obtain a dramatically more useful
"dust free" Type Ia supernovae {SNe Ia} dataset than available with the
previous GOODS searches. Moreover, this approach provides a strikingly
more efficient search-and-follow-up that is primarily pre- scheduled.
The resulting dark energy measurements do not share the major systematic
uncertainty at these redshifts, that of the extinction correction with a
prior. By targeting massive galaxy clusters at z > 1 we obtain a
five-times higher efficiency in detection of Type Ia supernovae in
ellipticals, providing a well-understood host galaxy environment. These
same deep cluster images then also yield fundamental calibrations
required for future weak lensing and Sunyaev-Zel'dovich measurements of
dark energy, as well as an entire program of cluster studies. The data
will make possible a factor of two improvement on supernova constraints
on dark energy time variation, and much larger improvement in systematic
uncertainty. They will provide both a cluster dataset and a SN Ia
dataset that will be a longstanding scientific resource.
ACS/WFC 10592
An ACS Survey of a Complete Sample 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
ACS/WFC imaging 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, resolution, and field of view
of ACS/WFC on HST enables a unique opportunity to study the detailed
structure of galaxies that sample all stages of the merger process.
Imaging will be done with the F439W and F814W filters {B and I-band} to
examine as a function of both luminosity and merger state {i} the
evidence at optical wavelengths of star formation and AGN activity and
the manner in which instabilities {bars and bridges} in the galaxies may
funnel material to these active regions, {ii} the relationship between
star formation and AGN activity, and {iii} the structural properties
{AGN, bulge, and disk components} and fundamental parameters {effective
radius and surface brightness} of LIRGs and their similarity with
putative evolutionary byproducts {elliptical, S0 and classical AGN host
galaxies}. This HST survey will also bridge the wavelength gap between a
Spitzer imaging survey {covering seven bands in the 3.6-160 micron
range} and a GALEX UV imaging survey of these galaxies, but will resolve
complexes of star clusters and multiple nuclei at resolutions well
beyond the capabilities of either Spitzer or GALEX. The combined
datasets will result in the most comprehensive multiwavelength study of
interacting and merging galaxies to date.
ACS/WFC 10618
The Light Echoes around V838 Monocerotis: MHD in 3 Dimensions,
Circumstellar Mapping, and Dust
V838 Monocerotis, which burst upon the astronomical scene in early 2002,
is a completely unanticipated new object. It underwent a large-amplitude
and very luminous outburst, during which its spectrum remained that of
an extremely cool supergiant. A rapidly evolving set of light echoes
around V838 Mon was discovered soon after the outburst, and quickly
became the most spectacular display of the phenomenon ever seen. The
light echoes, which were imaged by us with HST during 2002, provide the
means to accomplish four unique types of measurements based on continued
HST imaging during the event: {1} Study effects of MHD turbulence at
high resolution and in 3 dimensions; {2} Construct the first unambiguous
and fully 3-D map of a circumstellar dust envelope in the Milky Way; {3}
Study dust physics in a unique setting where the spectrum and light
curve of the illumination, and the scattering angle, are unambiguously
known; and {4} Determine the distance to V838 Mon through two
independent direct geometric techniques {polarimetry and angular
expansion rates}. Because of the extreme rarity of light echoes, this is
almost certainly the only opportunity to achieve such results during the
lifetime of HST. We propose a campaign during Cycle 14 of imaging the
echoes every 8 days for a total of 6 epochs, in order to fully map a
thin slab through the dust shell and achieve the other goals listed
above.
NIC2 10527
Imaging Scattered Light from Debris Disks Discovered by the Spitzer
Space Telescope Around 20 Sun-like
We propose to use the high contrast capability of the NICMOS coronagraph
to image a sample of newly discovered circumstellar disks associated
with sun-like stars. These systems were identified by their strong
thermal infrared emission with the Spitzer Space Telescope as part of
the Spitzer Legacy Science program titled, "The Formation and Evolution
of Planetary Systems {FEPS}." Modelling of the thermal excess emission
in the form of spectral energy distributions alone cannot distinguish
between narrowly confined high opacity disks and broadly distributed,
low opacity disks. However, our proposed NICMOS observations can, by
imaging the light scattered from this material. Even non- detections
will place severe constraints on the disk geometry, ruling out models
with high optical depth. Unlike previous disk imaging programs, our
program contains a well defined sample of solar mass stars covering a
range of ages from ~10Myrs to a few Gyrs, allowing us to study the
evolution of disks from primordial to debris for the first time. These
results will greatly improve our understanding of debris disks around
Sun- like stars at stellar ages nearly 10x older than any previous
investigation. Thus we will have fit a crucial piece into the puzzle
concerning the formation and evolution of our own solar system.
WFPC2 10745
WFPC2 CYCLE 14 INTERNAL MONITOR
This calibration proposal is the Cycle 14 routine internal monitor for
WFPC2, to be run weekly to monitor the health of the cameras. A variety
of internal exposures are obtained in order to provide a monitor of the
integrity of the CCD camera electronics in both bays {both gain 7 and
gain 15 -- to test stability of gains and bias levels}, a test for
quantum efficiency in the CCDs, and a monitor for possible buildup of
contaminants on the CCD windows. These also provide raw data for
generating annual super-bias reference files for the calibration
pipeline.
WFPC2 10749
Earth Flats
This proposal monitors flatfield stability. This proposal obtains
sequences of Earth streak flats to construct high quality flat fields
for the WFPC2 filter set. These flat fields will allow mapping of the
OTA illumination pattern and will be used in conjuction with previous
internal and external flats to generate new pipeline superflats. These
Earth flats will complement the Earth flat data obtained during cycles
4-13.
WFPC2 10750
WFPC2 Cycle 14 UV Earth Flats
Monitor flat field stability. This proposal obtains sequences of earth
streak flats to improve the quality of pipeline flat fields for the
WFPC2 UV filter set. These Earth flats will complement the UV earth flat
data obtained during cycles 8-13.
WFPC2 10751
WFPC2 CYCLE 14 Intflat Linearity Check and Filter Rotation Anomaly
Monitor
Intflat observations will be taken to provide a linearity check: the
linearity test consists of a series of intflats in F555W, in each gain
and each shutter. A combination of intflats, visflats, and earthflats
will be used to check the repeatability of filter wheel motions.
{Intflat sequences tied to decons, visits 1-18 in prop 10363, have been
moved to the cycle 14 decon proposal 10744 for easier scheduling.} Note:
long-exposure WFPC2 intflats must be scheduled during ACS anneals to
prevent stray light from the WFPC2 lamps from contaminating long ACS
external exposures.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are preliminary reports
of potential non-nominal performance that will be investigated.)
HSTARS:
9997 - REAcq (1,2,1) failed, search radius limit exceeded on FGS 1 @ 305/2354z
REAcq (1,2,1) scheduled @ 305/23:49:47 failed due to search radius limit
exceeded on FGS 1. Received ESB "a05" (Exceeded_SRL). Contacted PCS/SE
and advised of situation.
MAP prior to REAcq showed following errors: V1 -15.74, V2 -18.96, V3
-16.86, RSS 29.85
9998 - GSAcq (1,2,1) resulted in finelock backup (1,0,1) @ 306/0450Z
GSAcq (1,2,1) scheduled @ 306/04:46:42 resulted in finelock backup
(1,0,1) due to scan step limit exceeded on FGS 2.
OBAD #1 = V1 -1884.60, V2 -2076.04, V3 -980.32, RSS 2970.30
OBAD #2 = V1 14.76, V2 3.81, V3 4.67, RSS 15.94
OBAD MAP = V1 -0.54, V2 -11.58, V3 4.70, RSS 12.51
COMPLETED OPS REQUEST: (None)
COMPLETED OPS NOTES: (None)
SCHEDULED SUCCESSFUL FAILURE TIMES
FGS GSacq 10 10
FGS REacq 4 3 305/2354z (HSTAR 9997)
OBAD with Maneuver 26 26
SIGNIFICANT EVENTS: (None)
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