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Daily 3708



 
 
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Old October 4th 04, 04:59 PM
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Default Daily 3708

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT # 3708

PERIOD COVERED: DOYs 275-277

OBSERVATIONS SCHEDULED

NIC1/NIC2/NIC3 8793

NICMOS Post-SAA calibration - CR Persistence Part 4

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 images. Each observation will need its
own CRMAP, as different SAA passages leave different imprints on the
NICMOS detectors.

NIC1/Spacecraft 10382

NICMOS Focus Stability

The purpose of this activity is to determine if the best focus. This
program will execute in one month intervals starting about 1 month
after the last execution of proposal 9994 {the previous focus
monitoring program}. The program starts with a focus sweep using only
the NIC1 camera {visit 11}. The following observation is with the NIC2
camera {visit 12} after about 45 days. This pattern is repeated
throughout the period except for Feb 15 where also the NIC3 camera is
used. In total this will result in 9 orbits. Notice that VISIT #1 #2
refers to visits for #1 sequential visit number for a given camera #2
camera in question visit 32 is therefore the third visit for camera 2.

ACS/HRC/WFC 10367

ACS CCDs daily monitor- cycle 13 - part 1

This program consists of a set of basic tests to monitor, the read
noise, the development of hot pixels and test for any source of noise
in ACS CCD detectors. The files, biases and dark will be used to
create reference files for science calibration. This programme will be
for the entire lifetime of ACS.

ACS/WFC 10361

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 conjunction with previous
internal and external flats to generate new pipeline superflats. These
Earth flats will complement the Earth flat data obtained during cycles
4-12.

ACS/HRC 10272

A Snapshot Survey of the Sites of Recent, Nearby Supernovae

During the past few years, robotic {or nearly robotic} searches for
supernovae {SNe}, most notably our Lick Observatory Supernova Search
{LOSS}, have found hundreds of SNe, many of them in quite nearby
galaxies {cz 4000 km/s}. Most of the objects were discovered before
maximum brightness, and have follow-up photometry and spectroscopy;
they include some of the best-studied SNe to date. We propose to
conduct a snapshot imaging survey of the sites of some of these nearby
objects, to obtain late-time photometry that {through the shape of the
light and color curves} will help reveal the origin of their lingering
energy. The images will also provide high-resolution information on
the local environment of SNe that are far superior to what we can
procure from the ground. For example, we will obtain color-color and
color-magnitude diagrams of stars in these SN sites, to determine
their progenitor masses and constraints on the reddening. Recovery of
the SNe in the new HST images will also allow us to actually pinpoint
their progenitor stars in cases where pre-explosion images exist in
the HST archive. Use of ACS rather than WFPC2 will make our snapshot
survey even more valuable than our Cycle 9 survey. This Proposal is
complementary to our Cycle 13 archival proposal, in which we outline a
plan for using existing HST images to glean information about SN
environments.

ACS/WFC/WFPC2 10265

The Formation History of Andromeda

We propose deep observations of Andromeda's outer disk and giant tidal
stream, to reconstruct their star formation histories. As the nearest
giant galaxy, Andromeda offers the best testing ground for
understanding galaxy formation and evolution. Given the dramatic
increase in sensitivity offered by the ACS, we can now resolve stars
on the old main sequence in the other giant spiral of the Local Group,
and employ the same direct age diagnostics that have been used for
decades in the study of Galactic globular clusters. In Cycle 11, we
successfully observed a field in the Andromeda halo and constructed a
deep color-magnitude diagram reaching well below the oldest main
sequence turnoff. In Cycle 13, we propose to extend these observations
to the outer disk and tidal stream of Andromeda, to constrain their
star formation histories and compare them to that of the halo. The
combined observations from these two programs will offer a dramatic
advance in our understanding of the overall evolution of spiral
galaxies.

ACS/WFC 10260

The Most Massive Star Clusters: Supermassive Globular Clusters or
Dwarf Galaxy Nuclei?

Evidence is mounting that the most massive globular clusters, such as
Omega Centauri and M31-G1, may be related to the recently discovered
"Ultra-Compact Dwarfs" and the dense nuclei of dE, N galaxies.
However, no systematic imaging investigation of these supermassive
globular clusters -- at the level of Omega Cen and beyond -- has been
done, and we do not know what fraction of them might bear the
signatures {such as large effective radii or tidal tails} of having
originated as dE nuclei. We propose to use the ACS/WFC to obtain deep
images of 18 such clusters in NGC 5128 and M31, the two nearest rich
globular cluster systems. These globulars are the richest star
clusters that can be found in nature, the biggest of them reaching
10^7 Solar masses, and they are likely to represent the results of
star formation under the densest and most extreme conditions known.
Using the profiles of the clusters including their faint outer
envelopes, we will carry out state-of-the-art dynamical modelling of
their structures, and look for any clear evidence which would indicate
that they are associated with stripped satellites. This study will
build on our previous work with STIS and WFPC2 imaging designed to
study the 'Fundamental Plane' of globular clusters. When our new work
is combined with Archival WFPC2, STIS, and ACS material, we will also
be able to construct the definitive mapping of the Fundamental Plane
of globular clusters at its uppermost mass range, and confirm whether
or not the UCD and dE, N objects occupy a different structural
parameter space.

ACS/HRC 10238

The nature of quasar host galaxies: combining ACS imaging and VLT
Integral Field Spectroscopy.

We propose to perform ACS/F606W imaging of a complete sample of 29
quasar host galaxies {0.08z0.34}. The spatial resolving power of the
ACS HRC, in combination with the acquisition of empirical PSFs and
advanced deconvolution techniques, will allow to study in detail
structures on scales of a few tens of parsecs, and to access the inner
regions of the host galaxies, even in the presence of bright nuclei.
We demonstrate that combining deep spectroscopy with high resolution
imaging in stable PSF conditions definitely constitutes the solution
to characterize the complex physical properties of quasar host
galaxies, from their outer regions to the inner 0.1 kpc, where most of
the information on the interplay between quasars and their hosts is
hidden. We propose to combine new ACS images with existing Integral
Field VLT Spectra. We will map the stellar and gas velocity fields in
2D, constrain the mass models, derive the radial host M/L ratios, map
and characterize the stellar populations and the ionization state of
the gas.

ACS/WFC 10235

Dark vs. luminous matter in the CenA/M83 galaxy complex

The distribution of dark vs. luminous matter on scales of 0.1-1.0 Mpc
remains poorly understood. For a nearby group, the total mass can be
determined from the radius of "the zero-velocity surface", which
separates the group from the general Hubble flow. This new method
requires the measurement of accurate distances and radial velocities
of galaxies around the group, but gives total mass estimates
independent of assumptions about the state of relaxation or orbital
characteristics. The mass pertains to the group at the full scale to
which it is bound. Upon application in several nearest groups, the
method yields mass estimates in agreement with the sum of the virial
masses of subcomponents. However, the typical total M/L ratio for the
nearby groups of ~30 Mo/Lo implies a local mean density of matter
which is only 1/7 the canonical global density . The nearby complex of
galaxies around Cen A and M83 resembles our Local Group by the
dumb-bell concentration of objects around a pair of dominant galaxies.
Accurate distances have been acquired recently for ~20 group members
by the TRGB method using HST. We will measure TRGB distances to the 17
remaining galaxies in the region. These observations will constrain
the dynamical state of the halo surrounding the nearest giant E-galaxy
Cen A, providing a comparison with the halos of the nearest spirals.

ACS/SBC 10183

A Deep Far-UV Search for the Interacting Binary Population in M80

We propose to carry out a deep, far-ultraviolet {FUV}, time-resolved
survey for cataclysmic variables {CVs} and other dynamically-formed
objects in the globular cluster {GC} M80. This will include a search
for FUV counterparts to the 17 Chandra sources in our field of view,
which include 2 LMXBs and 5 X-ray selected CV candidates. Our goal is
to confirm these sources as interacting binaries and find any
additional CVs below the Chandra detection limit. We will achieve this
with 6 orbits of FUV imaging with the ACS/SB, plus one additional
orbit of NUV imaging with ACS/HRC. Since crowding is not a problem in
the FUV, this will yield time-resolved FUV photometry of all blue
objects in the cluster core. Our CV census will be both deep enough to
be essentially complete and ``broad'' enough to involve all of the
following CV characteristics: {1} UV brightness; {2} blue FUV spectral
shape; {3} strong CIV and HeII emission; {4} short time-scale {$sim$
minutes} variability {flickering, WD spin}; {6} intermediate
time-scale {$sim$ hours} variability {orbital variations}; {7} long
time-scale {$sim$ weeks} variability {dwarf nova eruptions}. We will
thus uncover the interacting binary population in M80. In addition,
our survey will detect numerous blue stragglers and hot white dwarfs,
as well as any other blue objects in the central regions of this
cluster.

ACS/HRC 10182

Towards a Comprehensive Understanding of Type Ia Supernovae: The
Necessity of UV Observations

Type Ia supernovae {SNe Ia} are very important to many diverse areas
of astrophysics, from the chemical evolution of galaxies to
observational cosmology which led to the discovery of dark energy and
the accelerating Universe. However, the utility of SNe Ia as
cosmological probes depends on the degree of our understanding of SN
Ia physics, and various systematic effects such as cosmic chemical
evolution. At present, the progenitors of SNe Ia and the exact
explosion mechanisms are still poorly understood, as are evolutionary
effects on SN Ia peak luminosities. Since early-time UV spectra and
light curves of nearby SNe Ia can directly address these questions, we
propose an approach consisting of two observational components: {1}
Detailed studies of two very bright, young, nearby SNe Ia with HST UV
spectroscopy at 13 epochs within the first 1.5 months after discovery;
and {2} studies of correlations with luminosity for five somewhat more
distant Hubble-flow SNe Ia, for which relative luminosities can be
determined with precision, using 8 epochs of HST UV spectroscopy
and/or broad-band imaging. The HST data, along with extensive
ground-based optical to near-IR observations, will be analyzed with
state-of-the-art models to probe SN Ia explosion physics and constrain
the nature of the progenitors. The results will form the basis for the
next phase of precision cosmology measurements using SNe Ia, allowing
us to more fully capitalize on the substantial past {and future}
investments of time made with HST in observations of high-redshift SNe
Ia.

NIC2 10176

Coronagraphic Survey for Giant Planets Around Nearby Young Stars

A systematic imaging search for extra-solar Jovian planets is now
possible thanks to recent progress in identifying "young stars near
Earth". For most of the proposed young {~ 30 Myrs} and nearby {~ 60
pc} targets, we can detect a few Jupiter-mass planets as close as a
few tens of AUs from the primary stars. This represents the first time
that potential analogs of our solar system - that is planetary systems
with giant planets having semi-major axes comparable to those of the
four giant planets of the Solar System - come within the grasp of
existing instrumentation. Our proposed targets have not been observed
for planets with the Hubble Space Telescope previously. Considering
the very successful earlier NICMOS observations of low mass brown
dwarfs and planetary disks among members of the TW Hydrae Association,
a fair fraction of our targets should also turn out to posses low mass
brown dwarfs, giant planets, or dusty planetary disks because our
targets are similar to {or even better than} the TW Hydrae stars in
terms of youth and proximity to Earth. Should HST time be awarded and
planetary mass candidates be found, proper motion follow-up of
candidate planets will be done with ground-based AOs.

WFPC2 10170

Atmospheric Variability on Uranus and Neptune

We propose Snapshot observations of Uranus and Neptune to monitor
changes in their atmospheres on time scales of weeks, months, and
years. Uranus is rapidly approaching equinox in 2007, with another 4
degrees of latitude becoming visible every year. Recent HST
observations during this epoch {including 6818: Hammel, Lockwood, and
Rages; 7885: Hammel, Karkoschka, and Marley; 8680: Hammel, Rages,
Lockwood, and Marley; and 8634: Rages, Hammel, Lockwood, Marley, and
McKay} have revealed strongly wavelength-dependent latitudinal
structure and the presence of numerous visible-wavelength cloud
features in the northern hemisphere. Long-term ground-based
observations {Lockwood and Thompson 1999} show seasonal brightness
changes whose origins are not well understood. Recent near-IR images
of Neptune obtained using adaptive optics on the Keck Telescope
together with images from our Cycle 9 Snapshot program {8634} show a
general increase in activity at south temperate latitudes as well as
the possible development of another Great Dark Spot. Further Snapshot
observations of these two dynamic planets will elucidate the nature of
long-term changes in their zonal atmospheric bands and clarify the
processes of formation, evolution, and dissipation of discrete albedo
features.

NIC2 10169

Star Formation in Luminous Infrared Galaxies: giant HII Regions and
Super Star Clusters

Luminous Infrared Galaxies {LIRGs, LIR = 10^11-10^12Lsol} and
Ultraluminous Infrared Galaxies {LIR10^12Lsol} account for
approximately 75% of all the galaxies detected in the mid-infrared in
the redshift range z=0-1.5. In the local universe it is found that
LIRGs are predominantly powered by intense star formation {SF}.
However, the physical conditions and processes governing such dramatic
activity over scales of tens to a few hundred parsecs are poorly
known. In the last decade HST has been playing a significant role,
mainly with the discovery of super star clusters {SSCs}, and more
recently, giant HII regions. Based on observations of a few LIRGs, we
found that these giant HII regions and associated SSCs appear to be
more common in LIRGs than in normal galaxies, and may dominate the
star formation activity in LIRGs. A larger sample is required to
address fundamental questions. We propose an HST/NICMOS targeted
campaign of a volume limited sample {v5200km/s} of 24 LIRGs. This
proposal will probe the role of giant HII regions in the overall
energetics of the current star formation, their relation to SSCs, and
the dependence of star formation properties on other parameters of
LIRGs. Such detailed knowledge of the SF properties of LIRGs in the
local universe is essential for understanding galaxies at high
redshift.

FGS 10106

An Astrometric Calibration of the Cepheid Period-Luminosity Relation

We propose to measure the parallaxes of 10 Galactic Cepheid variables.
When these parallaxes {with 1-sigma precisions of 10% or better} are
added to our recent HST FGS parallax determination of delta Cep
{Benedict et al 2002}, we anticipate determining the Period-Luminosity
relation zero point with a 0.03 mag precision. In addition to
permitting the test of assumptions that enter into other Cepheid
distance determination techniques, this calibration will reintroduce
Galactic Cepheids as a fundamental step in the extragalactic distance
scale ladder. A Period-Luminosity relation derived from solar
metallicity Cepheids can be applied directly to extragalactic solar
metallicity Cepheids, removing the need to bridge with the Large
Magellanic Cloud and its associated metallicity complications.

WFPC2 10071

WFPC2 CYCLE 12 Supplemental Darks Part 3/3

This dark calibration program obtains 3 dark frames every day to
provide data for monitoring and characterizing the evolution of hot
pixels.

ACS/WFC 10006

Black Hole X-ray Novae in M31

During A01-3 we found 22 Black Hole X-ray Novae {BHXN} in M31 using
Chandra, and with HST {WFPC2} found two optical counterparts. Our
results suggest either a surprisingly high ratio of BH to NS binaries,
or a surprisingly high duty cycle for BHXN. We propose to continue
this program, with the goals of understanding the relative number of
BH vs. NS X-ray binaries in the M31 bulge, and determining the orbital
period distribution and duty cycles of these BHXN. Continued
observations can determine the duty cycle. The new ACS will allow us
to go 2 mags deeper than the WFPC2, and could triple the number of
optical counterparts and therefore orbital period estimates. M31 is
the only galaxy near enough to allow this extragalactic survey for
BHXN.

FLIGHT OPERATIONS SUMMARY:

Significant Spacecraft Anomalies: (The following are preliminary
reports of potential non-nominal performance that will be
investigated.) None

COMPLETED OPS REQs:
17281-0 - HGA Offset Test @ 275/0936z

OPS NOTES EXECUTED: None


SCHEDULED SUCCESSFUL FAILURE TIMES
FGS Gsacq 21 21
FGS Reacq 25 25
FHST Update 23 23
LOSS of LOCK

SIGNIFICANT EVENTS:

Successfully supported two HGA Offset Test sessions, in order to
assess communication link margins applicable to Two-Gyro Science mode
operations. All test objectives were met. Separation angle vs RF
performance indicated HGA null roll-off as expected, near 9 degree
offset.


 




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