Status Report

Hubble Space Telescope Daily Report # 3183 – 21 Aug 2002

By SpaceRef Editor
August 21, 2002
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OBSERVATIONS SCHEDULED (see HSTARS below for possible observation problems)


NICMOS Post-SAA calibration – CR Persistence Part 1.

A new procedure proposed to alleviate the CR-persistence problem of NICMOS.
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
darks will be non-standard reference files available to users with a USEAFTER
date/time mark.


Dark Monitor-Part 2.

The Space Telescope Imaging Spectrograph (CCD) was used to monitor the darks.


Bias Monitor-Part 2.

The Space Telescope Imaging Spectrograph (CCD) was used to 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 in order
to build up high-S/N superbiases and track the evolution of hot columns.

STIS/MA1/MA2 8920

Cycle 10 MAMA Dark Measurements.

the MAMA detector dark noise, and is the primary means of checking on health of
the MAMA detectors systems through frequent monitoring of the background count

WFPC2 8938


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


Pure Parallel Imaging Program: Cycle 10.

The Space Telescope Imaging Spectrograph (CCD) was used to perform the default
archival pure parallel program for STIS during cycle 10.

FGS 9347

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
An estimate of the inclination yields a perturbation semi-major axis, Alpha =
0arcs0022, easily within the reach of HST/FGS astrometry.


Paschen-alpha Imaging of a SIRTF-Selected Nearby Galaxy Sample

We propose to carry out a NICMOS snapshot survey in the Paschen-alpha {PAlpha}
emission line and H-band of the sample of galaxies being observed at 3.5 — 160
microns as part of SIRTF Nearby Galaxies Survey {SINGS} and a related
time survey of starburst galaxies. The PAlpha images, accessible only from HST,
will be combined with groundbased HAlpha imaging to measure the extinction in
the star-forming centers of these galaxies, and obtain robust, extinction-
corrected maps of the massive star formation rate {SFR}. The PAlpha data by
themselves will provide reliable `extinction- free’ SFRs, and a
cross-calibration of the {dust–affected} HAlpha– and UV–based SFRs. The
PAlpha–based SFR measurements will extend the SFR-vs.-gas density law
{Schmidt–law} to surface densities at least 30 times higher than what is
accessible using HAlpha–based SFR measurements alone, bridging the gap between
normal galaxies and IR–luminous starbursts. Furthermore, the combination
of the
HST PAlpha images with the SIRTF images and spectra, as well as ancillary
ground–based UBVRIJHK images and GALEX UV images being obtained as part of the
SINGS project, will provide a definitive study of the radiative transfer of
starlight and dust heating in star–forming galaxies. The processed NICMOS
images will be incorporated into the public SINGS Legacy Data Archive, to
scores of follow-up studies by the astronomical community at large.


H_2 Imaging of Proto-Planetary Nebulae: Probing the Dynamics and Morphology

H_2 emission provides an excellent probe of the physical conditions in
nebulae {PNs} and also in proto- planetary nebulae {PPNs}, objects in
between the asymptotic giant branch {AGB} and PN phases. It is thought that the
shaping of the PN occurs when a fast wind interacts with the remnant of the AGB
progenitor during the PPN phase. The study of shock-excited H_2 in PPNs will
allow us to study this process. We request HST/NICMOS H_2 and complementary K
and H broad-band images of 13 PPNs with a range of spectral types of the
star. We presently have very high- resolution {~100, 000} H_2 spectra for 7 of
these, which we will use with the high-resolution images to study the velocity
structure of the fast wind. We will also explore the relationship between the
presence of H_2 and a bipolar shape for the nebula, as has been found in PNs.
However, the role of the equatorial torus is expected to be different in these
two cases, and in the PPNs it is expected to collimate the wind rather than
shield the molecules. Thus the H_2 in the PPNs is expected at the ends of the
lobes rather than in the torus. Radiatively-excited H_2 emission appears to be
common in PPNs with central stars of B spectral types; this appears to be a
transitional stage in the evolution of the H_2 in the nebula which these images
will help us to better understand.


A SNAPSHOT Survey of the Hot Interstellar Medium

We propose to obtain SNAPSHOT STIS echelle observations of key tracers of hot
interstellar gas {CIV, NV and SiIV} for selected FUSE Team OVI survey targets
with known UV fluxes. By taking advantage of the SNAPSHOT observing mode we
efficiently obtain a large number of spectra suitable for the study of the
highly ionized hot component of the interstellar medium {ISM}. Our goals are to
explore the physical conditions in and distribution of such gas, as well as to
explore the nature of the interfaces between the hot ISM and the other
interstellar gas phases. Using inter–comparisons of the various ionic ratios
for CIV, NV, OVI and SiIV, we will be able to discriminate between the various
models for the production of the highly ionized gas in the Galactic ISM. The
survey will also enable detailed studies of regions already known to
contain hot
gas through X-ray emission measurements {e.g., SNRs and radio loops}. The
proposed SNAPSHOT observations will extend our previous Cycle 9 survey {which
was compromised by the STIS side 1 failure}, and should roughly double the
number of stars for which high quality STIS observations of the important hot
gas tracers are available, enabling us to derive a truly global view of the hot

STIS 9435

Systematic Search for Rotation at the Base of Outflows from T Tauri Stars

We wish to search for rotation signatures in the initial portion {first 100 AU}
of a sample of outflows emanating from T Tauri stars {TTSs}. This project
originates from our detection of systematic transverse radial velocity
shifts in
STIS spectra of the DG Tau jet {Bacciotti et al., 2002}. The shifts,
observed in
a region where the flow is already collimated, but has not yet manifestly
interacted with its environment, are consistent with the predictions of
centrifugal launching models, and may constitute the first observed indication
for rotation in the initial portion of a jet flow. Rotation is a fundamental
ingredient in star formation theories, thus we propose to confirm the above
result by carrying out a systematic survey in similar flows. We plan to
take for
each jet a STIS spectrum in the 6300 — 6800 Angstrom range, with the slit
perpendicular to the flow direction and at a distance of about 0.”3 from the
source {i.e., in our targets, 40 — 70 AU along the jet depending on
angle}. Since the flows are resolved transversely with HST, the proposed slit
orientation allows for the direct detection of systematic velocity shifts.
found, we will check for consistency between the sense of rotation observed and
that of the underlying disk through CO interferometric measurements. As a
by-product, estimates of the excitation conditions across the flow {including
ionization fraction} and of the mass outflow rates will be derived.

GO 9449

UV Spectrum of the Massive X-ray Binary LS 5039

LS 5039 is a massive X-ray binary with non-thermal radio emission, relativistic
jets, and probably high energy Gamma- ray emission. It appears to be one of the
closest of the Galactic microquasars, stellar-sized engines that produce
relativistic jets like extragalactic quasars. We recently discovered that the
system is a 4.1 day binary with a very eccentric orbit {indicating large mass
loss in the supernova event that gave birth to the system}. The companion is
probably a neutron star, but a black hole companion is viable if the system
inclination is small. Here we propose to obtain the first UV observations
of the
binary to determine fundamental properties about the O6.5 V{{f}} optical star
and the mass transfer process. The UV spectrophotometry will allow us to
accurately the interstellar extinction and system distance, and the unreddened
spectrum will provide information on the optical star’s effective temperature,
spectral classification, and surface abundances. The stellar wind lines in the
FUV provide the means to measure the O- star’s wind terminal velocity and mass
loss rate, and these parameters will allow us to determine if the X-ray
luminosity can be generated by wind accretion alone. We plan to observe these
wind lines at both orbital conjunction phases to search for evidence of changes
in the wind structure caused by proximity to the X-ray source’s radiation
accretion disk wind, and jets.

ACS 9472

A Snapshot Survey for Gravitational Lenses among z >= 4.0 Quasars

Over the last few years, the Sloan Digital Sky Survey has revolutionized the
study of high-redshift quasars by discovering over 200 objects with redshift
greater than 4.0, more than doubling the number known in this redshift
The sample includes eight of the ten highest redshift quasars known. We propose
a snapshot imaging survey of a well-defined sample of 250 z > 4.0 quasars in
order to find objects which are gravitationally lensed. Lensing models
magnification bias predict that at least 4% of quasars in a flux-limited sample
at z > 4 will be multiply lensed. Therefore this survey should find of order 10
lensed quasars at high redshift; only one gravitationally lensed quasar is
currently known at z > 4. This survey will provide by far the best sample to
date of high-redshift gravitational lenses. The observed fraction of lenses can
put strong constraints on cosmological models, in particular on the
constant Lambda. In addition, magnification bias can significantly bias
estimates of the luminosity function of quasars and the evolution thereof; this
work will constrain how important an effect this is, and thereby give us a
better understanding of the evolution of quasars and black holes at early
epochs, as well as constrain models for black hole formation.

ACS 9480

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
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. NICMOS 9484 The NICMOS Parallel Observing Program We propose to manage the default set of pure parallels with NICMOS. Our experience with both our GO NICMOS parallel program and the public parallel NICMOS programs in cycle 7 prepared us to make optimal use of the parallel opportunities. The NICMOS G141 grism remains the most powerful survey tool for HAlpha emission-line galaxies at cosmologically interesting redshifts. It is particularly well suited to addressing two key uncertainties regarding the global history of star formation: the peak rate of star formation in the relatively unexplored but critical 1<= z <= 2 epoch, and the amount of star formation missing from UV continuum-based estimates due to high extinction. Our proposed deep G141 exposures will increase the sample of known HAlpha emission- line objects at z ~ 1.3 by roughly an order of magnitude. We will also obtain a mix of F110W and F160W images along random sight-lines to examine the space density and morphologies of the reddest galaxies. The nature of the extremely red galaxies remains unclear and our program of imaging and grism spectroscopy provides unique information regarding both the incidence of obscured star bursts and the build up of stellar mass at intermediate redshifts. In addition to carrying out the parallel program we will populate a public database with calibrated spectra and images, and provide limited ground- based optical and near-IR data for the deepest parallel fields. NICMOS 9485 Completing A Near-Infrared Search for Very Low Mass Companions to Stars within 10 pc of the Sun Most stars are fainter and less massive than the Sun. Nevertheless, our knowledge of very low mass {VLM} red dwarfs and their brown dwarf cousins is quite limited. Unknown are the true luminosity function {LF}, multiplicity fraction, mass function, and mass-luminosity relation for red and brown dwarfs, though they dominate the Galaxy in both numbers and total mass. The best way to constrain these relations is a search for faint companions to nearby stars. Such a search has several advantages over field surveys, including greater sensitivity to VLM objects and the availability of precise parallaxes from which luminosities and masses can be derived. We propose to complete our four-filter NICMOS snapshot search for companions to stars within 10 pc. With a 10 sigma detection limit of M_J ~ 20 at 10 pc, we can detect companions between 10 and 100 AU that are at least 9 mag fainter than the empirical end of the main sequence and at least 6.5 mag fainter than the brown dwarf Gl 229B. When completed, our search will be the largest, most sensitive, volume-limited search for VLM companions ever undertaken. Our four-filter search will permit unambiguous identification of VLM-companion candidates for follow-up observation. Together with IR speckle and deep imaging surveys, our program will firmly establish the LF for VLM companions at separations of 1-1000 AU and the multiplicity fraction of all stars within 10 pc. STIS 9505 The Evolution of Molecular Clouds. The combined STIS, FUSE and ground-based results will yield information needed to understand the role of ablation in the evolution of the central clouds. ACS/CAL 9558 ACS weekly Test 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 9565 ACS Post-SMOV UV Contamination Monitor This programme continues the UV sensitivity monitoring campaign {ACS SMOV proposal 9010} of the HRC and SBC after the end of the SMOV period. ACS 9567 SBC Dark Current Dark current measurements will be made for the ACS SBC once a week. ACS/WFC 9584 ACS Default {Archival} Pure Parallel Program II. The Advanced Camera for Surveys (WFC) was used to test ACS pure parallels. WFPC2 9634 POMS Test Proposal: WFII targeted parallel archive proposal The parallel opportunities available with WFPC2 in the neighborhood of bright galaxies are treated in a slightly different way from the normal pure parallels. Local Group galaxies offer the opportunity for a closer look at young stellar populations. Narrow-band images in F656N can be used both to identify young stars via their emission lines, and to map the gas distribution in star-forming regions. Thus, the filter F656N is added to the four standard filters. Near more distant galaxies, up to about 10 Mpc, we can map the population of globular clusters; for this purpose, F300W is less useful, and only F450W, F606W, and F814W will be used. ACS 9672 Grism/Prism Calibration A Planetary Nebula in the LMC and two Galactic White Dwarfs are observed through the prisms of the HRC and the SBC to measure: 1} the dispersion of the prisms and its field dependence; 2} the prisms throughput and its field dependence. Therefore, these measurements will be carried out at several positions on the chip including the centre and the corners of the HRC and SBC chips. WFPC2 9676 POMS Test Proposal: WFII parallel archive proposal used to take parallel images of random areas of the sky, following the recommendations of the 2002 Parallels Working Group. POMS 9677 POMS Test Proposal: WFII backup parallel archive proposal This is a POMS test proposal designed to simulate scientific plans. FLIGHT OPERATIONS SUMMARY: HSTARS (For details see HSTAR 8766 - Telemetry Bars on "A" string Reads 1 PCS Mnemonic Out of Limits @232/0303z CCS "A" String Telemetry Bar reads 1 PCS mnemonic OOL @ 232/03:30Z, but when clicked on, there are no mnemonics violated. Under investigation. COMPLETED OPS REQs: 16833-1 - Battery 1 Capacity Test Script @232/1800z (opened at 232/1851z) OPS NOTES EXECUTED: None SCHEDULED SUCCESSFUL FAILURE TIMES FGS GSacq 11 11 FGS REacq 3 3 FHST Update 24 24 LOSS of LOCK Operations Notes: SIGNIFICANT EVENTS: Battery 1 Capacity Test started 232/18:43Z (OR 16833-1). Discharge began nominally @ 232/22:07Z and is estimated to continue for 14 - 16 hours. EPS and SI SEs are monitoring test from the STOCC, a follow-on Flash Report will issued after discharge is terminate. NBL 02.3 (FGS 3, NOBL 5 (FF & RMS), STIK, filler - Parazynski, Williams, Nicollier), Day 3 of 5, 7 am - 5 pm @ JSC NBL HST On-Orbit Checkout of real-time WSC interface scheduled daily 231 - 238 with GDOC, STOCC Ops (SIMOR), HITT, and CCS using CCS "G" String with CCS Release 4.0.1 and PRD O06100Q1. The purpose of this testing is to verify CCS Release 4.0.1 (IP) capability to interface through the IP Packet Filters to WSC for real-time telemetry and commands.

SpaceRef staff editor.