Status Report

NASA Hubble Space Telescope Daily Report # 3805

By SpaceRef Editor
February 28, 2005
Filed under , ,
NASA Hubble Space Telescope Daily Report # 3805
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HUBBLE SPACE TELESCOPE – Continuing to collect World Class Science

DAILY REPORT        # 3805

PERIOD COVERED: DOYs 56-58

OBSERVATIONS SCHEDULED

NIC1/NIC2/NIC3 8792

NICMOS Post-SAA calibration – CR Persistence Part 3

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.

ACS/WFC 10417

Host Galaxies and Environments of the Most Massive Black Holes in the
Early Universe

The existence of luminous quasars with billion solar mass black holes
at high redshift poses important questions about the relation between
the formation and evolution of the earliest galaxies and quasars in
the universe: how could these high-redshift black holes accrete matter
so quickly and so efficiently? Is the quasar phase connected to the
formation of galactic bulge in the earliest epoch? Was the black
hole-bulge mass relation observed locally already established at
high-redshift? We will use ACS/WFC to obtain rest-frame UV imaging of
five quasars at z~4 with the highest estimated black hole mass, of the
order 10 billion solar masses. The goal of the HST observation is to
directly detect their host galaxies and to probe their galactic
environment. These quasars are likely among the most massive and
luminous host galaxies at high-redshift, providing ideal targets for
direct detection. The rest-frame UV properties measured with HST will
be combined with rest-frame optical, mid to far-IR oberservations of
these quasars to measure the star-formation rate, to estimate the
stellar age and mass of the host galaxy, and to probe the
quasar/starburst connection, quasar triggering mechanism and relation
between black hole and bulge formation at the highest possible
redshift. One of the targets, PSS 2322+1944 {z=4.17}, is a
gravitational lensed quasar with a nearly complete Einstein ring in CO
emission, providing a unique opportunity to study the small scale
structure of a high-redshift quasar host galaxy.

NIC3/WFPC2 10403

Ultraviolet Imaging of the UDF

The Hubble Deep Field North has uninterrupted observations at
wavelengths from Far- UV through NICMOS H-band, but the UDF goes no
bluer than B-band. We propose to complete the UDF coverage with deep
ultraviolet imaging of the Ultra-Deep Field {UDF} with the ACS-SBC in
the Far-UV {1500 Angstrom} and WFPC2 in the Near-UV {F300W}. We will
reach point source limits of ABmag=28.5, a factor of ten fainter than
the GALEX ultradeep surveys. Our dataset will add to the value of the
UDF legacy, and requires the unique capabilities of HST. In the spirit
of the UDF, we submit this proposal in the Treasury category. We
request a modest allocation of observing time for a Treasury program:
62 orbits. We will provide science quality images and photometric
catalogs to enable a range of research topics by the community. The
science goals of the team are to investigate the episode of strong
star formation activity in galaxies out to z=1, through the rest-frame
FUV luminosity function and the internal color structure of galaxies.
Far-UV number counts suggest that moderate redshift {z~0.5} starbursts
are undergoing a single, rapid burst of star-formation. We will
investigate this result by measuring the faint-end slope, alpha, of
the luminosity function. We will measure the star formation properties
of moderate redshift starburst galaxies and compare their morphologies
in the UV, optical, and near-IR. This catalog of starbursts will also
be important to the astronomical community in correlating unobscured
star-formation with the sources detected in the Spitzer Space
Telescope legacy observations of the field. With the high spatial
resolution data, will set strict limits on the flux escaping in
intermediate redshift {1 < z < 2} galaxies at wavelengths below the rest-frame Lyman limit, and thus infer the contribution of star forming galaxies at z~5 to the metagalactic ionizing radiation.

ACS/HRC 10401

A Proper Motion Search for Intermediate Mass Black Holes in Globular
Clusters

Establishing the presence or absence of intermediate-mass black holes
{IMBH} in globular clusters is crucial for understanding the evolution
of dense stellar systems. We propose a systematic search for IMBHs by
conducting an imaging/proper motion study of the centers of five of
the closest, most centrally concentrated Galactic globular clusters.
ACS/HRC observations allow for accurate proper motion measurements for
stars all the way into the center of each cluster. Our approach
consists of exploiting the blue/near-ultraviolet wavelength range in
each of cycles 13 and 14, in order to dim both the bright red giants
and the background of faint red stars, hence alleviating the crowding
problems experienced by previous studies. Both filter and target
selection are critical for the success of this project, and no
previous HST program has an appropriate combination to allow proper
motion measurements for most stars into the very centers of crowded
clusters. The velocity measurements will allow us to: {i} place
constraints on the mass of a central black hole in each cluster
{detailed calculations show that the proposed observations are
sufficient to detect any central black hole with a mass as low as 3000
solar masses at the greater than 3 sigma level}; {ii} derive the
internal velocity dispersion as a function of cluster radius; {iii}
verify or reject previous reports of cluster rotation; and {iv}
directly measure any velocity anisotropy as a function of radius.

ACS/HRC 10375

Stability of the ACS CCD: Flat fielding, Photometry, Geometry

This program will verify that the low frequency flat fielding, the
photometry, and the geometric distortion are stable in time and across
the field of view of the CCD detectors. A moderately crowded stellar
field, located ~6′ West of the center of the cluster 47 Tuc, is
observed every three months with the WFC and HRC using the full suite
of broad and narrow band filters. The same field has been observed
during SMOV to derive low frequency corrections to the ground flats
and to create a master catalogue of positions and magnitudes from
dithered observations of the cluster. In Cycles 11-12, this field was
observed again using single pointings at various roll angles. The
positions and magnitudes of objects are used to monitor local and
large scale variations in the plate scale and the sensitivity of the
detectors. The Cycle 13 program will continue to monitor these effects
and will derive an independent measure of the detector CTE.

ACS/WFC 10374

ACS photometric Stability

This program consists of three parts. In the first part we will
observe a subset of the ACS white dwarfs with HRC and ACS to verify
repeatability to ~0.2%, because the filter shifts are based on
photometric differences between stars of ~1%. These observations are
also required to establish relative magnitudes of the primary WD
standards at the 0.1% level. Targets should be GD153 and G191B2B,
which seems to have the largest V mag error of ~0.008 mag. One orbit
on the most important filters, including the grism and the prisms,
should be expended with each camera for both stars for a total of 4
orbits. In the second part will observe with HRC and WFC a solar
analog star, P330E, to estimate any shifts in the short and the long
wavelength cutoffs of selected filters. Complete filter bandpasses can
be derived directly from the ratio of grism observations with and
without the filter in place. The grism is on filter wheel 1, while
four filters of interest F330W, F344N, F660N, and F814W are on wheel
2. Each grism observation requires 3 settings: filter alone,
filter+grism, and grism alone. In the third part we obtain high S/N
photometric and spectroscopic observations of three red stars, VB-8
{M7}, 2M0038+18 {L3.5} and 2M0559-14 {T5} with HRC and WFC to verify
the photometry at the new standard position and to obtain accurate
calibration {1% or better} of the grism spectra.

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/NIC3 10339

PANS

Type Ia supernovae {SNe Ia} provide the only direct evidence for an
accelerating universe, an extraordinary result that needs the most
rigorous test. The case for cosmic acceleration rests on the
observation that SNe Ia at z = 0.5 are about 0.25 mag fainter than
they would be in a universe without acceleration. A powerful and
straightforward way to assess the reliability of the SN Ia measurement
and the conceptual framework of its interpretation is to look for
cosmic deceleration at z > 1. This would be a clear signature of a
mixed dark-matter and dark-energy universe. Systematic errors in the
SNe Ia result attributed to grey dust or cosmic evolution of the SN Ia
peak luminosity would not show this change of sign. We have obtained a
toehold on this putative “epoch of deceleration” with SN 1997ff at z
= 1.7, and 3 more at z > 1 from our Cycle 11 program, all found and
followed by HST. However, this is too important a test to rest on just
a few objects, anyone of which could be subject to a lensed
line-of-sight or misidentification. Here we propose to extend our
measurement with observations of twelve SNe Ia in the range 1.0 < z < 1.5 or 6 such SNe Ia and 1 ultradistant SN Ia at z = 2, that will be discovered as a byproduct from proposed Treasury and DD programs. These objects will provide a much firmer foundation for a conclusion that touches on important questions of fundamental physics.

ACS/WFC 10257

Astrometric and Photometric Study of NGC 6397 for Internal Motions,
Dark Binaries, and X-Ray Sources

We propose to observe the central regions of the globular cluster NGC
6397 with ACS/WFC once per month for the 10 months of its visibility
in Cycle 13. The project has three main goals: {1} Measure internal
motions for roughly 3000 stars within 150 arcseconds of the cluster
center, using archival WFPC2 as a first epoch. The motion of the
typical star will be measured to 10-20%. We will detect any central
black hole {BH} with a mass greater than 1000 solar masses, and will
also measure core-collapse signatures such as anisotropy. {2} Conduct
the first-ever search for heavy binaries by looking for the
astrometric “wobble” of the luminous secondary. We should find all
heavy binaries in the field with separations between 1 and 5 AU and
periods between 3 months and 5 years. {3} Search for opticall
counterparts to X-ray sources found by Chandra.

ACS/HRC 10198

Probing the Dynamics of the Galactic Bar through the Kinematics of
Microlensed Stars

The observed optical depths to microlensing of stars in the Galactic
bulge are difficult to reconcile with our present understanding of
Galactic dynamics. The main source of uncertainty in those comparisons
is now shifting from microlensing measurements to the dynamical models
of the Galactic bar. We propose to constrain the Galactic bar models
with proper motion observations of Bulge stars that underwent
microlensing by determining both the kinematic identity of the
microlensed sources and the importance of streaming motions. The
lensed stars are typically farther than randomly selected stars.
Therefore, our proper motion determinations for 36 targeted MACHO
events will provide valuable constraints on the dynamics of bulge
stars as a function of distance. The first epoch data for our proposed
events is already available in the HST archive so the project can be
completed within a single HST cycle. The exceptional spatial
resolution of HST is essential for completion of the project.
Constraints on the total mass in the bulge will ultimately lead to the
determination of the amount of dark matter in inner Galaxy.

NIC2 10173

Infrared Snapshots of 3CR Radio Galaxies

Radio galaxies are an important class of extragalactic objects: they
are one of the most energetic astrophysical phenomena and they provide
an exceptional probe of the evolving Universe, lying typically in high
density regions but well-represented across a wide redshift range. In
earlier Cycles we carried out extensive HST observations of the 3CR
sources in order to acquire a complete and quantitative inventory of
the structure, contents and evolution of these important objects.
Amongst the results, we discovered new optical jets, dust lanes,
face-on disks with optical jets, and revealed point-like nuclei whose
properties support FR-I/BL Lac unified schemes. Here, we propose to
obtain NICMOS infrared images of 3CR sources with z<0.3 as a major enhancement to an already superb dataset. We aim to deshroud dusty galaxies, study the underlying host galaxy free from the distorting effects of dust, locate hidden regions of star formation and establish the physical characteristics of the dust itself. We will measure frequency and spectral energy distributions of point-like nuclei, expected to be stronger and more prevalent in the IR, seek spectral turnovers in known synchrotron jets and find new jets. We will strongly test unified AGN schemes and merge these data with existing X-ray to radio observations. The resulting database will be an incredibly valuable resource to the astronomical community for years to come.

FLIGHT OPERATIONS SUMMARY:

Significant Spacecraft Anomalies: (The following are preliminary
reports of potential non-nominal performance that will be
investigated.)

HSTAR 9726 : GSAcq(2,1,1) results in finelock backup (2,0,2) @
58/2023z- The GSAcq(2,1,1) scheduled at 058/20:22:47 – 058/20:30:02
resulted to finelock backup (2,0,2) using FGS#2, due to scan step
limit exceeded on FGS2. The FM Updates scheduled prior GSacq both
passed with small error.Possible Observations affected: ACS 151 – 152,
NIC 59. Under investigation.

COMPLETED OPS REQs: None

OPS NOTES EXECUTED:

1308-0  Adjust Recharge Ratio Limits for HIGHSUN/ORBIT Time @058/2356z

                             SCHEDULED     SUCCESSFUL    FAILURE TIMES FGS Gsacq                  30                       30 FGS Reacq                  14                       14 FHST Update                35                       35 LOSS of LOCK

SIGNIFICANT EVENTS: None

SpaceRef staff editor.