Daily Report # 4373

Notice: For the foreseeable future, the daily reports may contain apparent
discrepancies between some proposal descriptions and the listed instrument
usage. This is due to the conversion of previously approved ACS WFC or HRC
observations into WFPC2, or NICMOS observations subsequent to the loss of
ACS CCD science capability in late January.


HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT # 4373

PERIOD COVERED: UT May 30, 2007 (DOY 150)

OBSERVATIONS SCHEDULED

ACS/SBC 10862

Comprehensive Auroral Imaging of Jupiter and Saturn during the International
Heliophysical Year

A comprehensive set of observations of the auroral emissions from Jupiter
and Saturn is proposed for the International Heliophysical Year in 2007, a
unique period of especially concentrated measurements of space physics
phenomena throughout the solar system. We propose to determine the physical
relationship of the various auroral processes at Jupiter and Saturn with
conditions in the solar wind at each planet. This can be accomplished with
campaigns of observations, with a sampling interval not to exceed one day,
covering at least one solar rotation. The solar wind plasma density
approaching Jupiter will be measured by the New Horizons spacecraft, and a
separate campaign near opposition in May 2007 will determine the effect of
large-scale variations in the interplanetary magnetic field {IMF} on the
Jovian aurora by extrapolation from near-Earth solar wind measurements. A
similar Saturn campaign near opposition in Jan. 2007 will combine
extrapolated solar wind data with measurements from a wide range of
locations within the Saturn magnetosphere by Cassini. In the course of
making these observations, it will be possible to fully map the auroral
footprints of Io and the other satellites to determine both the local
magnetic field geometry and the controlling factors in the electromagnetic
interaction of each satellite with the corotating magnetic field and plasma
density. Also in the course of making these observations, the auroral
emission properties will be compared with the properties of the near-IR
ionospheric emissions {from ground-based observations} and non thermal radio
emissions, from ground-based observations for Jupiter?s decametric radiation
and Cassini plasma wave measurements of the Saturn Kilometric Radiation
{SKR}.

FGS 11214

HST/FGS Astrometric Search for Young Planets Around Beta Pic and AU Mic

Beta Pic and AU Mic are two nearby Vega-type debris disk stars. Both of
these disk systems have been spatially resolved in exquisite detail,
predominantly via the ACS coronagraph and WFPC-2 cameras onboard HST. These
images exhibit a wealth of morphological features which provide compelling
indirect evidence that these systems likely harbor short-period planetary
body{ies}. We propose to use the superlative astrometric capabilities of
HST/FGS to directly detect these planets, hence provide the first direct
planet detection in a Vega-type system whose disk has been imaged at high
spatial resolution.

NIC1/NIC2/NIC3 8794

NICMOS Post-SAA calibration - CR Persistence Part 5

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 10603

Multiwavelength Imaging of Edge-on Protoplanetary Disks: Quantifying the
Growth of Circumstellar Dust

Young, edge-on circumstellar disks are uniquely valuable laboratories for
the study of planet formation. In these objects, the central star is
occulted from direct view, significant PSF artifacts are absent, and the
disk is clearly seen as a central dust lane flanked by faint disk reflected
light. The detailed morphology of these nebulae and its variation with
wavelength provide crucial information on the disk internal structure and
the properties of its constituent dust grains. A key observable is the slope
defining the wavelength dependence of the dust scattering opacity, which
becomes shallower when grain growth has taken place; multiwavelength
resolved disk images are the key dataset enabling such measurements. Recent
analyses of three different edge-on disks have revealed a diversity in their
dust properties that is indicative of different degrees of dust grain
evolution having taken place in each system. This characterization of disk
grain growth, when applied comparatively to a larger sample of these
objects, would enable the construction of an evolutionary sequence of young
disks at successive stages on the road to planet formation. In pursuit of
this goal, we have identified a sample of 15 edge-on disks previously
discovered by HST or groundbased telescopes, but for which high fidelity,
high spatial resolution images do not yet exist in both the optical and
near-infrared. We propose broad- band multicolor imaging with NICMOS of all
these targets, and ACS imaging of nine of these targets In combination with
existing data, the proposed images will form a complete database of high
resolution optical/near-IR images for these 15 disk systems. Scattered light
modeling will be used to derive the disk structure and dust properties,
yielding results that will be of fundamental importance for our
understanding of grain properties during protoplanetary disk evolution.

NIC2 11157

NICMOS Imaging Survey of Dusty Debris Around Nearby Stars Across the Stellar
Mass Spectrum

Association of planetary systems with dusty debris disks is now quite
secure, and advances in our understanding of planet formation and evolution
can be achieved by the identification and characterization of an ensemble of
debris disks orbiting a range of central stars with different masses and
ages. Imaging debris disks in starlight scattered by dust grains remains
technically challenging so that only about a dozen systems have thus far
been imaged. A further advance in this field needs an increased number of
imaged debris disks. However, the technical challege of such observations,
even with the superb combination of HST and NICMOS, requires the best
targets. Recent HST imaging investigations of debris disks were
sample-limited not limited by the technology used. We performed a search for
debris disks from a IRAS/Hipparcos cross correlation which involved an
exhaustive background contamination check to weed out false excess stars.
Out of ~140 identified debris disks, we selected 22 best targets in terms of
dust optical depth and disk angular size. Our target sample represents the
best currently available target set in terms of both disk brightness and
resolvability. For example, our targets have higher dust optical depth, in
general, than newly identified Spitzer disks. Also, our targets cover a
wider range of central star ages and masses than previous debris disk
surveys. This will help us to investigate planetary system formation and
evolution across the stellar mass spectrum. The technical feasibility of
this program in two-gyro mode guiding has been proven with on- orbit
calibration and science observations during HST cycles 13, 14, and 15.

NIC3 11080

Exploring the Scaling Laws of Star Formation

As a variety of surveys of the local and distant Universe are approaching a
full census of galaxy populations, our attention needs to turn towards
understanding and quantifying the physical mechanisms that trigger and
regulate the large-scale star formation rates {SFRs} in galaxies.

NIC3 11082

NICMOS Imaging of GOODS: Probing the Evolution of the Earliest Massive
Galaxies, Galaxies Beyond Reionization, and the High Redshift Obscured
Universe

Deep near-infrared imaging provides the only avenue towards understanding a
host of astrophysical problems, including: finding galaxies and AGN at z
7, the evolution of the most massive galaxies, the triggering of star
formation in dusty galaxies, and revealing properties of obscured AGN. As
such, we propose to observe 60 selected areas of the GOODS North and South
fields with NICMOS Camera 3 in the F160W band pointed at known massive M
10^11 M_0 galaxies at z 2 discovered through deep Spitzer imaging. The
depth we will reach {26.5 AB at 5 sigma} in H_160 allows us to study the
internal properties of these galaxies, including their sizes and
morphologies, and to understand how scaling relations such as the Kormendy
relationship evolved. Although NIC3 is out of focus and undersampled, it is
currently our best opportunity to study these galaxies, while also sampling
enough area to perform a general NIR survey 1/3 the size of an ACS GOODS
field. These data will be a significant resource, invaluable for many other
science goals, including discovering high redshift galaxies at z 7, the
evolution of galaxies onto the Hubble sequence, as well as examining
obscured AGN and dusty star formation at z 1.5. The GOODS fields are the
natural location for HST to perform a deep NICMOS imaging program, as
extensive data from space and ground based observatories such as Chandra,
GALEX, Spitzer, NOAO, Keck, Subaru, VLT, JCMT, and the VLA are currently
available for these regions. Deep high-resolution near-infrared observations
are the one missing ingredient to this survey, filling in an important gap
to create the deepest, largest, and most uniform data set for studying the
faint and distant universe. The importance of these images will increase
with time as new facilities come on line, most notably WFC3 and ALMA, and
for the planning of future JWST observations.

WFPC2 10902

The Nearest Luminous Blue Compact Galaxies: A Window on Galaxy Formation

As we move to intermediate and high redshifts, Luminous Blue Compact
Galaxies {LBCGs} become increasingly common. The nearest LBCGs, with their
violent starbursts and rich populations of super star clusters {SSCs} and
globular clusters {GCs}, thus provide ideal laboratories for studying galaxy
evolution. Many LBCGs appear to be involved in mergers between dwarf
galaxies, triggering their starbursts. The starburst regions in LBCGs
consist of numerous young star clusters, whose populations are both easily
measurable with HST and easily modelled. Studying cluster populations
provides a powerful probe of the starburst and merger history which is
possible neither for closer objects {of which there are too few} or for
those at high redshift {which are too far away}. We have previously studied
the closest LBCG with WFPC2 and found hundreds of bright compact SSCs and
GCs. In particular, we found a population of intermediate-age {~2 Gyr} GCs,
indicating a past event of massive cluster formation. We now propose a
multi-wavelength study of the three other LBCGs with the highest known
number of SSCs. The extinction is small in these galaxies and age estimates
robust. The age distribution of GCs and SSCs will be used to study the past
evolution of the galaxies. For each LBCG, we will map its cluster formation
history, unveiling its merger and starburst history, and thereby shed light
on some of the processes involved in galaxy evolution at high redshift.

WFPC2 11022

WFPC2 Cycle 15 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: (None)

COMPLETED OPS REQUEST: (None)

SCHEDULED SUCCESSFUL

FGS GSacq 09 09
FGS REacq 04 04
OBAD with Maneuver 26 26

COMPLETED OPS NOTES: (None)