Daily Report # 4146

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT # 4146

PERIOD COVERED: UT June 29, 2006 (DOY 180)

OBSERVATIONS SCHEDULED

FGS 10612

Binary Stars in Cyg OB2: Relics of Massive Star Formation in a
Super-Star Cluster

We propose to make a high angular resolution SNAP survey of the
massive stars in the nearby, super-star cluster Cyg OB2. We will use
FGS1r TRANS mode observations to search for astrometric companions in
the separation range of 0.01 to 1.00 arcsec and in the magnitude
difference range smaller than 4 magnitudes. The observations will test
the idea that the formation of very massive stars involves mergers and
the presence of nearby companions. Discovery of companions to massive
stars in this relatively nearby complex will provide guidance in the
interpretation of apparently supermassive stars in distant locations.
The search for companions will also be important for verification of
fundamental parameters derived from spectroscopy, adjustments to main
sequence fitting and distance estimations, determining third light
contributions of eclipsing binaries, identifying wide colliding wind
binaries, studying the relationship between orbital and spin angular
momentum, and discovering binaries amenable to future mass
determinations. The massive star environment in Cyg OB2 may be similar
to the kinds found in the earliest epoch of star formation, so that a
study of the role of binaries in Cyg OB2 will help us understand the
formation processes of the first stars in the Universe.

NIC1 10143

Ultracool companions to the nearest L dwarfs

We propose to conduct the most sensitive survey to date for low mass
companions to nearby L dwarfs. We will use NICMOS to image targets
drawn from a volume-complete sample of 70 L dwarfs within 20 parsecs.
The combination of infrared imaging and proximity will allow us to
search for T dwarf companions at separations as small as 1.6 AU. This
is crucial, since no ultracool binaries are currently known with
separations exceeding 15 AU. Only 10 dwarfs in this sample have
previous HST observations primarily at optical wavelengths. With the
increased sensitivity of our survey, we will provide the most
stringent test to date of brown dwarf models which envisage formation
as ejected stellar embryos. In addition, our observations will be
capable of detecting binaries with mass ratios as low as 0.3, and will
therefore also test the apparent preference for equal- mass ultracool
binaries. Finally, our observations offer the best prospect to date of
detecting companions significantly cooler than the coolest t dwarf
currently known.

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.

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 z0.3 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.

NIC2 10527

Imaging Scattered Light from Debris Disks Discovered by the Spitzer
Space Telescope Around 20 Sun-like Stars

We propose to use the high contrast capability of the NICMOS
coronagraph to image a sample of newly discovered circumstellar disks
associated with sun-like stars. These systems were identified by their
strong thermal infrared emission with the Spitzer Space Telescope as
part of the Spitzer Legacy Science program titled, "The Formation and
Evolution of Planetary Systems {FEPS}." Modelling of the thermal
excess emission in the form of spectral energy distributions alone
cannot distinguish between narrowly confined high opacity disks and
broadly distributed, low opacity disks. However, our proposed NICMOS
observations can, by imaging the light scattered from this material.
Even non- detections will place severe constraints on the disk
geometry, ruling out models with high optical depth. Unlike previous
disk imaging programs, our program contains a well defined sample of
solar mass stars covering a range of ages from ~10Myrs to a few Gyrs,
allowing us to study the evolution of disks from primordial to debris
for the first time. These results will greatly improve our
understanding of debris disks around Sun-like stars at stellar ages
nearly 10x older than any previous investigation. Thus we will have
fit a crucial piece into the puzzle concerning the formation and
evolution of our own solar system.

NIC2 10808

Morphologies of spectroscopically-confirmed "red and dead" galaxies at
z~2.5

Using a combination of wide-field near-infrared imaging and very deep
follow-up near- infrared spectroscopy we have identified a population
of massive "red and dead" galaxies at z~2.5. The galaxies lack
emission lines and have strong Balmer/4000 Angstrom breaks,
demonstrating directly that they have evolved stellar populations.
These objects are very likely progenitors of massive ellipticals today
and may be descendants of the first generation of galaxies. We propose
to image 10 of these objects with the NIC2 camera to determine their
morphologies. The goals are to 1} determine whether they have the
sizes of present-day early-types or are more compact, as predicted by
models, 2} determine the morphology, using visual classification and
quantitative methods, and 3} constrain the evolution of the Kormendy
relation from z~2.5 to the present. These observations will show
whether the oldest and most massive galaxies at z~2.5 were already
fully formed or still in the process of assembly.

NIC3 10899

Identifying z7 galaxies from J-dropouts

NICMOS Parallel Imaging campaigns covered enough sky {250 pointings}
with enough sensitivity in the 110W and 160W filters to identify 6
extremely red resolved sources which are prime candidates for J-band
dropouts. Their complete absence of detectable J band flux can be
caused by an opaque Lyman cut-off at z=8-10. We propose to followup
these candidates with NICMOS imaging and jointly propose Spitzer IRAC
photometry. Deep F110W and Spitzer/IRAC 3.5/4.8 micron imaging will
confirm if any of these candidates are indeed Lyman Break galaxies
observed less than 500 Myrs after the Big Bang. Genuine LBGs will
remain undetected in F110W, while being detected with flat spectra in
the IRAC bands. The combined SED will provide information about the
stellar mass of these galaxies, and the possible presence of evolved
stars or dust reddening. The proposed observations will be sensitive
enough to detect the F110W flux from galaxies as red as {J-H}=2.8 {AB
mags, 5 sigma}. If any of the candidates are detected with bluer
colors, they will most likely be exceptional "Distant Red Galaxies" at
z of 4 to 6. The proposed data will constrain the stellar populations
of these extraordinarily red galaxies, which would be candidates for
the earliest, most massive galaxies which formed.

WFPC2 10744

WFPC2 Cycle 14 Decontaminations and Associated Observations

This proposal is for the WFPC2 decons. Also included are instrument
monitors tied to decons: photometric stability check, focus monitor,
pre- and post-decon internals {bias, intflats, kspots, & darks}, UV
throughput check, VISFLAT sweep, and internal UV flat check.

FLIGHT OPERATIONS SUMMARY:

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

HSTARS:

10326 REAcq(2,1,2) failed to RGA Control @ 181/03:21:36z

REAcq(2,1,2) at 181/03:18:40 failed to RGA control due to stop flag
(QF2STOPF) on FGS-2 at 03:21:36. Previous GSAcq(2,1,2) at 01:42:38 was
successful. Pre-acquisition OBAD's were successful with RSS error
corrections of 1540.27 and 14.68.

COMPLETED OPS REQUEST:
17804-0 MAGN Test @ 180/1309z
17803-0 Set SSR 1 & 3 Overwrite Flags to Prevent Overwrite for Science
Data @ 180/1731z
17805-1 Recover ACS to Side 2 Operations (thru step 3.12)

COMPLETED OPS NOTES:
1496-0 Update SSR-1/SSR-3 Overwrite Flag SA1 Limits @ 180/1813z
1497-0 Switch ACS ground system command mode to RIU-B @ 180/2105z
(CCS-F/D/H), 181/0343z (CCS-A)

SCHEDULED SUCCESSFUL FAILURE TIMES
FGS
GSacq 10 10
FGS
REacq 04 03
181/03:21:36z (HSTAR # 10326)
OBAD with Maneuver 28 28
LOSS of LOCK


SIGNIFICANT EVENTS:

MA/GN Mode recorder Dump Test (Bteasdel, Thu, 29 Jun 2006 10:40:09,
Summary Extract) - Ops Request 17804-0 was executed on DOY 2006/180
between 12:18:54 and 12:44:32, to test the process of dumping Science
data via the MAT, through TDRSS and to the ground. The test
performance was successful.

Flash Report: SSR

Overwrite Ops Briefing (Ntull, Thu, 29 Jun 2006 11:13:37, Summary
Extract) - Flash Report: SSR Overwrite Change Operations Briefing -
The Ops Briefing on the SSR Overwrite Change was held on Thursday,
06/29/06. Approval was granted to reconfigure SSR-1 "Overwrite" flags
to prohibit overwriting of science data upon safemode entry.
Commanding is scheduled to occur at 1:30 pm EST on 06/29/06.

Flash Report: Change to SSR

Overwrite Flags (Ssands, Thu, 29 Jun 2006 14:24:20, Summary Extract) -
Ops Request 17803-0 to set the SSR-1 and SSR-3 Overwrite Flags for
Storage Area 1 (science data) to prevent overwrite was completed at
180/17:31:17. Ops Note 1496-0 to adjust the limits for the Overwrite
Flags was completed at 180/18:12:57.

Flash Report: ACS Side-2

Switch status - MEB-2 in Boot (Rstevens, Thu, 29 Jun 2006 19:45:56,
Summary Extract) - At 180/21:01, the transition to ACS Side-2
operations was started via OPS Request 17805. The ACS MEB-2 was
successfully to transitioned to Boot Mode at 180/22:39 (operate relay
closed) and a memory dump collected of the Side-2 EEPROM. Payload FSW
has verified the contents of the Side-2 EEPROM matches the expected
version (JV0008). Commanding to update the ACS Side 2 EEPROM to JV0019
is in progress and no anomalous telemetry has been observed.

Flash Report: ACS Side-2

At 181/12:20 the loading of ACS Side 2 EEPROM (JV0019) was completed
and verified by the Payload FSW team. ACS was transitioned
successfully to Operate mode at 181/13:12 on Side 2. All mechanisms
except correctors were initialized and placed in their home positions.
The WFC and HRC TEC have also been enabled and successfully cooled
their respective CCD s to -66.7 dgC. The WFC and HRC CCD detectors
have both been powered on and initialized. No anomalous telemetry has
been observed for any ACS sub-system on Side 2. ACS remained in this
configuration until ~181/14:00, when it was reconfigured for science
intercept on Sunday evening (184/00:00).