Hubble Space Telescope Daily Report #2844 — 5 Apr 2001

HUBBLE SPACE TELESCOPE

DAILY REPORT #2844

PERIOD COVERED: 0000Z (UTC) 04/04/01 – 0000Z (UTC) 04/05/01

Daily Status Report as of 095/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

1.1 Completed STIS/CCD/MA2 8681 (Snapshot Survey of Variability of
Narrow and Broad Associated Absorption Lines in Quasars)

The Space telescope Imaging Spectrograph (CCD and MA2) was used to
investigate the variability in the strength of absorption lines in quasar
spectra which is definitive proof that we are observing material that is
physically associated with the quasars. This proposal will conduct a STIS
snapshot survey to provide second epoch observations of 37 quasars with
narrow associated or broad absorption lines {NALs and BALs}, previously
observed with the FOS. At high redshift several intrinsic NALs and about
two thirds of BALs are known to vary, often in accord with continuum
variability. The amplitudes increase and the timescales decrease with
decreasing quasar luminosity. The proposal completed nominally.

1.2 Completed Two Sets of WF/PC-2 8827 (Cycle 9 Supplemental Darks pt2/3)

The WF/PC-2 was used to obtain three dark frames every day to
provide data for monitoring and characterizing the evolution of hot
pixels. The proposal completed nominally.

1.3 Completed Three Sets of STIS/CCD 8864 (CCD Dark Monitor-Part 2)

The Space Telescope Imaging Spectrograph (CCD) was used to monitor
the darks for the CCD. The proposal completed nominally.

1.4 Completed STIS/CCD/MA1 8606 (Determining the Nature of the Variable
Absorption in AGN: Monitoring NGC 3783 with HST and Chandra)

The Space Telescope Imaging Spectrograph (CCD and MA1) was used to
investigate Seyfert 1 galaxies, many of which show intrinsic UV absorption
lines, characterized by high moderate widths, significant outflow
velocities, and variability on time scales as small as days. Seyferts with
UV absorption also show variable X-ray “warm absorbers”, characterized by
O VII and O VIII absorption edges, which suggests a common
origin. Variability monitoring is the key to understanding the absorbers,
by providing their radial locations, densities, and evolution in
ionization, column density, velocity, and coverage of the inner active
nucleus. The proposal completed with no problems.

1.5 Completed Four Sets of WF/PC-2 9244 (POMS Test Proposal: WFII
Parallel Archive Proposal Continuation)

The WF/PC-2 was used to perform a generic target version of the
Archival Pure Parallel program. The program will be used to take parallel
images of random areas of the sky, following the recommendations of the
Parallels Working Group. The observations completed with no anomalous
activity.

1.6 Completed Three Sets of WF/PC-2 8816 (Cycle 9 UV Earthflats)

The WF/PC-2 was used to obtain sequences of Earth streak flats to
improve the quality of pipeline flat fields for the WFPC2 UV filter set and
in order to monitor flat field stability. There were no reported problems.

1.7 Completed STIS/CCD/MA1/MA2 8857 (MAMA Sensitivity and Focus Monitor C9)

The Space Telescope Imaging Spectrograph (CCD, MA1 and MA2) was
used to monitor the sensitivity of each MAMA grating mode to detect any
change due to contamination or other causes. There were no problems.

1.8 Completed STIS/CCD 8865 (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, to build up high-S/N superbiases and track the evolution of hot
columns. The proposal completed with no anomalous activity.

1.9 Completed FGS/2R 8831 (Long Term Stability in Transfer Mode)

Fine Guidance Sensor #2R was used to continue a SMOV3a proposal and
a cycle 8 calibration proposal to monitor the FGS2R S-curves during its
first 1.5 years in orbit. The standard star Upgren69, known to be a point
source at FGS resolution, will be observed in Transfer Mode at the center
of the FGS2R FOV using both the F583W filter and the 2/3 PUPIL stop. The
observations completed with no reported problems.

1.10 Completed Three Sets of STIS/CCD 8851 (Sparse Field CTE test
{Cycle 9})

The Space Telescope Imaging Spectrograph (CCD) was used to perform
CTE measurements that are made using the “sparse field test”, along both
the serial and parallel axes. The proposal completed with no reported
anomalies.

1.11 Completed Two Sets of STIS/CCD/MA1 8582 (UV Detectability of
Bright Quasars in the Sloan Fields)

The Space Telescope Imaging Spectrograph (CCD and MA1) was used to
examine the He II Ly alpha absorption at 304{1+z} Angstrom which is a far
more sensitive tracer of the intergalactic medium {IGM} than its H I
counterpart. The recent detections of such absorption in four quasars,
albeit with limited data quality and a small sample size, demonstrate the
great potential of such a probe. There were no reported problems.

1.12 Completed Two Sets of STIS/MA1 8843 (Cycle 9 MAMA Dark Measurements)

The Space Telescope Imaging Spectrograph (MA1) was used to perform
the routine monitoring of the MAMA detector dark noise. The proposal
completed nominally.

1.13 Completed WF/PC-2 8682 (A Snapshot Study of 0bservational Cosmology)

The WF/PC-2 was used to examine the observational constraints on
the cosmic star formation history that is currently among the most active
fields in observational cosmology. The most widely used tracer of the
co-moving volume-averaged star formation rate {SFR} is the UV luminosity
density, which early results found to peak at z~1- 2. The apparent
identification of the primary epoch of metal production and star formation
in the Universe led to intense theoretical and observational
interest. Nevertheless, and remarkably for such a fundamental observation,
little is known about the history of star formation in the Universe beyond
its global average. There were no reported anomalies.

1.14 Completed WF/PC-2 8720 (Masses and Multiplicity of Nearby Free-
floating Methane and L Dwarfs)

The WF/PC-2 was used to observe 50 very-low-mass objects in the
solar neighborhood with spectral types of L0 and later {including several
dwarfs with Methane absorption bands in their atmospheres}. These objects
will be observed in two filter bands with the aim to identify close
companions, measure their colors, and to obtain first epoch data of the
newly discovered binaries. The observations completed nominally.

1.15 Completed STIS/CCD 8259 (The Origin of Blue Wings on NLR Line
Profiles)

The Space Telescope Imaging Spectrograph (CCD) was used to attempt
understanding the kinematics of the Narrow Line Region {NLR} in Seyfert
galaxies. The observational signature being looked for is the famous `blue
wing’ found on the OIIILambda5007 lines of almost all Seyfert
galaxies. The proposal completed with no reported problems.

1.16 Completed WF/PC-2/STIS/CCD 8679 (Constraining the Age of the
Oldest Stars from the White Dwarf Cooling Sequence in M4)

The WF/PC-2 and the Space Telescope Imaging Spectrograph (CCD) were
used to search for the oldest and hence coolest white dwarfs {WDs} in M4,
the nearest Galactic globular cluster to the Sun. New models for cooling
hydrogen white dwarfs predict that their colors should become bluer, rather
than redder, with increasing age. The goal is to test these models and at
the same time constrain the age of M4. The proposal completed with no
problems.

1.17 Completed STIS/CCD 8591 (The Smallest Nuclear Black Holes)

The Space Telescope Imaging Spectrograph (CCD) was used to observe
small nuclear black holes which are the last major unexplored part of BH
parameter space, searching for the smallest BHs that HST can possibly
find. The proposal completed with no reported anomalies.

1.18 Completed STIS/CCD/MA2 8711 (C/O Abundance Ratios Across WCL
Planetary Nebulae With Strong PAH And Crystalline Silicate Emission)

The Space Telescope Imaging Spectrograph (CCD and MA2) was used to
measure the required high angular resolution across compact nebulae for the
crucial abundance-diagnostic lines of C ii 2326 Angstrom and O ii 2470
Angstrom. ISO has discovered cool O-rich crystalline silicate and water-
ice emission in the far-IR spectra of several planetary nebulae {PNe} which
show very strong hot PAH {polycyclic aromatic hydrocarbon, carbon-rich}
emission bands in their near- and mid-IR spectra. All of these PNe are
young and compact and of low-ionization, and have cool H-deficient Wolf-
Rayet central stars. The correlation with carbon-rich WCL Wolf-Rayet
central stars suggests that the phenomenon is associated with a recent
transition from an O-rich to a C-rich phase by the evolving objects,
following the exposure of 3rd dredge-up enriched material. For these
nebulae, the gas-phase C/O ratios {two of the nebulae have the largest C/O
ratios known} are strongly correlated with the PAH feature strength. The
unexpected discovery of cool oxygen-rich particles around them suggests
that strong C/O abundance gradients may be present in the nebulae. The
observations completed nominally.

2.0 FLIGHT OPERATIONS SUMMARY:

2.1 Guide Star Acquisitions:

Scheduled Acquisitions: 7

Successful: 7

Scheduled Re-acquisitions: 8

Successful: 8

2.2 FHST Updates:

Scheduled: 19

Successful: 19

2.3 Operations Notes:

Using ROP SR-1A, the SSR EDAC error counter was cleared twice.

No problems were encountered while checking out the CCS Release 3.4
on the “B” string.

A TTR was written for a required re-transmission at 095/0253Z
during a NSSC-1 load. Per ROP NS-5, the engineering report was
subsequently reset at 095/0258Z.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

Continuation of normal science observations and calibrations.