NASA Hubble Space Telescope Daily Report # 3550

HUBBLE SPACE TELESCOPE – Continuing to collect World Class Science

DAILY REPORT # 3550

PERIOD COVERED: DOY 42

OBSERVATIONS SCHEDULED

ACS 9984

Cosmic Shear With ACS Pure Parallels

Small distortions in the shapes of background galaxies by foreground
mass provide a powerful method of directly measuring the amount and
distribution of dark matter. Several groups have recently detected
this weak lensing by large-scale structure, also called cosmic shear.
The high resolution and sensitivity of HST/ACS provide a unique
opportunity to measure cosmic shear accurately on small scales. Using
260 parallel orbits in Sloan textiti {F775W} we will measure for the
first time: beginlistosetlength sep0cm setlengthemsep0cm setlength
opsep0cm em the cosmic shear variance on scales <0.7 arcmin, em the
skewness of the shear distribution, and em the magnification effect.
endlist Our measurements will determine the amplitude of the mass
power spectrum sigma_8Omega_m^0.5, with signal-to-noise {s/n} ~ 20,
and the mass density Omega_m with s/n=4. They will be done at small
angular scales where non-linear effects dominate the power spectrum,
providing a test of the gravitational instability paradigm for
structure formation. Measurements on these scales are not possible
from the ground, because of the systematic effects induced by PSF
smearing from seeing. Having many independent lines of sight reduces
the uncertainty due to cosmic variance, making parallel observations
ideal.

ACS/HRC 9747

An Imaging Survey of the Statistical Frequency of Binaries Among
Exceptionally-Young Dynamical Families in the Main Asteroid Belt

We propose an ambitious SNAPSHOT program to determine the frequency of
binaries among two very young asteroid families in the Main Belt, with
potentially profound implications. These families {of C- and S-type}
have recently been discovered {Nesvorny et al. 2002, Nature 417, 720},
through dynamical modeling, to have been formed at 5.8 MY and 8.3 MY
ago in catastrophic impact events. This is the first time such
precise and young ages have been assigned to a family. Main-belt
binaries are almost certainly produced by collisions, and we would
expect a young family to have a significantly higher frequency of
binaries than the background, because they may not yet have been
destroyed by impact or longer-term gravitational instabilities. In
fact, one of the prime observables from such an event should be the
propensity for satellites. This is the best way that new numerical
models for binary production by collisions {motivated largely by our
ground-based discoveries of satellites among larger asteroids}, can be
validated and calibrated. HST is the only facility that can be used to
search for binaries among such faint objects {V>17.5}. We will also
measure two control clusters, one being an "old" family, and the other
a collection of background asteroids that do not have a family
association, and further compare with our determined value for the
frequency of large main-belt binaries {2%}. We request visits to 180
targets, using ACS/HRC.

ACS/HRC/WFC 10059

CCD Daily Monitor

This program consists of basic tests to monitor, the read noise, the
development of hot pixels and test for any source of noise in ACS CCD
detectors. This programme will be executed once a day for the entire
lifetime of ACS.

ACS/WFPC2 9488

Cosmic Shear – with ACS Pure Parallel Observations

The ACS, with greater sensitivity and sky coverage, will extend our
ability to measure the weak gravitational lensing of galaxy images
caused by the large scale distribution of dark matter. We propose to
use the ACS in pure parallel {non- proprietary} mode, following the
guidelines of the ACS Default Pure Parallel Program. Using the HST
Medium Deep Survey WFPC2 database we have measured cosmic shear at
arc-min angular scales. The MDS image parameters, in particular the
galaxy orientations and axis ratios, are such that any residual
corrections due to errors in the PSF or jitter are much smaller than
the measured signal. This situation is in stark contrast with
ground-based observations. We have also developed a statistical
analysis procedure to derive unbiased estimates of cosmic shear from a
large number of fields, each of which has a very small number of
galaxies. We have therefore set the stage for measurements with the
ACS at fainter apparent magnitudes and smaller, 10 arc-second scales
corresponding to larger cosmological distances. We will adapt existing
MDS WFPC2 maximum likelihood galaxy image analysis algorithms to work
with the ACS. The analysis would also yield an online database similar
to that in archive.stsci.edu/mds/

FGS 9969

FGS Astrometry of the Extrasolar Planet of Epsilon Eridani

We propose observations with HST/FGS in Position Mode to determine the
astrometric elements {perturbation orbit semimajor axis and
inclination} of the candidate extra-solar planet around the K2 V star
Epsilon Eridani that has been detected by Doppler spectroscopy. These
observations will also permit us to determine the actual mass of the
planet by providing the sin{i} factor which can not be determined with
the radial velocity method. High precision radial velocity {RV}
measurements spanning the years 1980.8–2000.0 for the nearby {3.22
pc} star Epsilon Eri show convincing variations with a period of ~ 7
yrs. These data represent a combination of six independent data sets
taken with four different telescopes. A least squares orbital solution
using robust estimation yields orbital parameters of period, P = 6.9
yrs, velocity K- amplitude = 19 m/s, eccentricity e = 0.6, projected
companion mass M_B sin{i} = 0.83 M_Jupiter. An estimate of the
inclination yields a perturbation semi-major axis, Alpha = 0arcs0022,
easily within the reach of HST/FGS astrometry.

NIC/NIC3 9865

The NICMOS Parallel Observing Program

We propose to continue managing the NICMOS pure parallel program.
Based on our experience, we are well prepared to make optimal use of
the parallel opportunities. The improved sensitivity and efficiency of
our observations will substantially increase the number of
line-emitting galaxies detected. As our previous work has
demonstrated, the most frequently detected line is Halpha at
0.7<z<1.9, which provides an excellent measure of current star
formation rate. We will also detect star-forming and active galaxies
in other redshift ranges using other emission lines. The grism
observations will produce by far the best available Halpha luminosity
functions over the crucial–but poorly observed–redshift range where
galaxies appear to have assembled most of their stellar mass. This key
process of galaxy evolution needs to be studied with IR data; we found
that observations at shorter wavelengths appear to have missed a large
fraction of the star-formation in galaxies, due to dust reddening. We
will also obtain deep F110W and F160W images, to examine the space
densities and morphologies of faint red galaxies. In addition to
carrying out the public parallels, we will make the fully reduced and
calibrated images and spectra available on-line, with some
ground-based data for the deepest parallel fields included.

NICMOS 8791

NICMOS Post-SAA calibration – CR Persistence Part 2

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.

STIS/CCD 10017

CCD Dark Monitor-Part 1

Monitor the darks for the STIS CCD.

STIS/CCD 10019

CCD Bias Monitor – Part 1

Monitor the bias in the 1×1, 1×2, 2×1, and 2×2 bin settings at gain=1,
and 1×1 at gain = 4, to build up high-S/N superbiases and track the
evolution of hot columns.

STIS/CCD 10085

STIS Pure Parallel Imaging Program: Cycle 12

This is the default archival pure parallel program for STIS during
cycle 12.

STIS/CCD 9776

Black Holes in Big Galaxies with Small Bulges

In early-type galaxies the black hole {BH} mass is tightly correlated
with the bulge velocity dispersion. This correlation suggests that the
BH mass is determined by local processes in the central part of the
galaxy. However, the bulge dispersion in these galaxies is correlated
with the disk circular speed which in turn correlates with the
inferred halo circular speed {the "disk-halo conspiracy"}. For this
reason, existing data cannot decide whether the BH mass is set by the
bulge dispersion or the disk or halo circular speed. We propose to
break this degeneracy by weighing the BH in 3 Sc galaxies in which the
ratio of bulge circular speed to bulge velocity dispersion is large,
leading to large differences between BH masses predicted from these
quantities. These measurements will increase the number of carefully
studied Sc bulges from one to four and will determine whether the
masses of nuclear BHs are set by {presumably baryonic} processes in
galaxy bulges or by {presumably non-baryonic} processes in their dark
halos.

STIS/CCD/MA1 9511

Connecting the UV and X-ray Warm Absorbers in NGC 5548

In the last Chandra cycle, we were awarded a joint Chandra/HST
proposal to study the warm absorber in NGC 5548 and to obtain a
definitive answer about the connection between the warm absorber and
the UV absorber in this object. We are confident that the deep Chandra
observation {500 ksec} will allow for an unprecedented determination
of the kinematic components in the warm absorber as well as accurate
column density measurements from several line series. However, two new
lines of investigation that appeared after the submission of the
Chandra/HST proposal, suggest that the original modest request for HST
time will not suffice to obtain reliable column density measurements
for the UV absorber. In view of the new evidence, we need a a higher
S/N in the proposed observations to allow for accurate UV column
densities determination. Absorption features in both the UV and warm
absorbers are known to be variable. Therefore, it will be highly
unfortunate if the large investment of Chandra time will not be
accompanied by enough simultaneous HST time to ensure an accurate
measurements of the UV absorber. Without these it will be very
difficult to draw conclusions concerning the relationship between the
two absorbers. We therefore ask for 20 additional STIS E140M Echelle
orbits.

STIS/CCD/MA1 9848

A SNAPSHOT Survey of Sharp-Lined Early B-Type Stars

Although spectrum synthesis studies of the UV spectra of sharp-lined
main sequence B stars provide us with some our best determinations of
the abundances of the Fe group and neutron capture elements and the
chemical evolution in our galaxy and the Magellanic Clouds, the HST
archive is virtually devoid of high resolution spectra of the bright
nearby B stars that have become to be regarded as abundance standards.
For example, there are NO observations of HR 1886, iota Her, and tau
Her, the sharpest-lined representatives {V sin i < 5 km/s} of spectral
classes B1 V, B3 IV-V and B5 IV, and only a few tiny spectral
intervals of gamma Peg {B2 IV}. Information on the abundances of the
Fe group is important for computing opacities for stellar evolution
calculations and for determining astrophysical f-values. There are no
suitable galactic standards in the HST database to compare with recent
HST/STIS observations of B stars in the Magellanic Clouds and the
likely future observations of similar objects in M31 and other nearby
galaxies. To correct this deficiency, we propose SNAPSHOT observations
with the STIS E140M and E230M gratings of 33 of the best bright
abundance standards in nearby clusters and the galactic field. Using
this data we will determine the abundances of the Fe group and heavy
elements using the technique of spectrum synthesis with LTE and NLTE
treatments. We waive the proprietary period.

WFPC2 10070

WFPC2 CYCLE 12 Supplemental Darks Part 2/3

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

WFPC2 10082

POMS Test Proposal: WFII backup parallel archive proposal

This is a POMS test proposal designed to simulate scientific plans

WFPC2 10084

WFII parallel archive proposal

This is the generic target version of the WFPC2 Archival Pure Parallel
program. The program will be used to take parallel images of random
areas of the sky, following the recommendations of the 2002 Parallels
Working Group.

FLIGHT OPERATIONS SUMMARY:

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

COMPLETED OPS REQs: None

OPS NOTES EXECUTED: None

                      SCHEDULED     SUCCESSFUL    FAILURE TIMES
FGS GSacq          06                        06
FGS REacq          08                        08
FHST Update        16                        16
LOSS of LOCK

SIGNIFICANT EVENTS: None