HUBBLE SPACE TELESCOPE - Continuing to collect World Class
Science
DAILY REPORT #4692
PERIOD COVERED: 5am September 9 - 5am September 10, 2008
(DOY 253/0900z-254/0900z)
OBSERVATIONS SCHEDULED
NIC1/NIC2/NIC3 11820
NICMOS Post-SAA Calibration - CR Persistence Part 7
Internals for CR persistence
NIC2 11548
NICMOS Imaging of Protostars in the Orion A Cloud: The
Role of
Environment in Star Formation
We propose NICMOS observations of a sample of 252
protostars identified
in the Orion A cloud with the Spitzer Space Telescope.
These
observations will image the scattered light escaping the
protostellar
envelopes, providing information on the shapes of outflow
cavities, the
inclinations of the protostars, and the overall
morphologies of the
envelopes. In addition, we ask for Spitzer time to obtain
55-95 micron
spectra of 75 of the protostars. Combining these new data
with existing
3.6 to 70 micron photometry and forthcoming 5-40 micron
spectra measured
with the Spitzer Space Telescope, we will determine the
physical
properties of the protostars such as envelope density,
luminosity,
infall rate, and outflow cavity opening angle. By
examining how these
properties vary with stellar density (i.e. clusters vs
groups vs
isolation) and the properties of the surrounding molecular
cloud; we can
directly measure how the surrounding environment
influences protostellar
evolution, and consequently, the formation of stars and
planetary
systems. Ultimately, this data will guide the development
of a theory of
protostellar evolution.
NIC3 11545
A NICMOS Survey of Newly-Discovered Young Massive Clusters
We are on the cusp of a revolution in massive star
research triggered by
2MASS and Spitzer/GLIMPSE, and now is the ideal time to
capitalize on
these projects by performing the first survey of massive
stars in young
stellar clusters throughout the Galactic plane. A search of
the 2MASS
and GLIMPSE surveys has produced over 450 newly-identified
massive
stellar cluster candidates in the Galactic plane which are
hidden from
our view at optical wavelengths due to extinction. Here we
propose a
program of 29 orbits to image the most promising candidate
clusters in
broad and narrow band filters using HST/NICMOS. We will be
complementing
these observations with approved Spitzer and Chandra
programs, numerous
approved and planned ground-based spectroscopic
observations, and
state-of-the-art modeling. We expect to substantially
increase the
numbers of massive stars known in the Galaxy, including
main sequence
stars and post-main sequence stars in the Red Supergiant,
Luminous Blue
Variable and Wolf-Rayet stages. Ultimately, this program
will address
many of the fundamental topics in astrophysics: the slope
to the initial
mass function (IMF), an upper-limit to the masses of
stars, the
formation and evolution of the most massive stars,
gamma-ray burst (GRB)
progenitors, the chemical enrichment of the interstellar
medium, and
nature of the first stars in the Universe.
WFPC2 11113
Binaries in the Kuiper Belt: Probes of Solar System
Formation and
Evolution
The discovery of binaries in the Kuiper Belt and related
small body
populations is powering a revolutionary step forward in
the study of
this remote region. Three quarters of the known binaries
in the Kuiper
Belt have been discovered with HST, most by our snapshot
surveys. The
statistics derived from this work are beginning to yield
surprising and
unexpected results. We have found a strong concentration
of binaries
among low-inclination Classicals, a possible size cutoff
to binaries
among the Centaurs, an apparent preference for nearly
equal mass
binaries, and a strong increase in the number of binaries
at small
separations. We propose to continue this successful
program in Cycle 16;
we expect to discover at least 13 new binary systems,
targeted to
subgroups where these discoveries can have the greatest
impact.
WFPC2 11130
AGNs with Intermediate-mass Black Holes: Testing the Black
Hole-Bulge
Paradigm, Part II
The recent progress in the study of central black holes in
galactic
nuclei has led to a general consensus that supermassive
{10^6-10^9 solar
mass} black holes are closely connected with the formation
and
evolutionary history of large galaxies, especially their
bulge
component. Two outstanding issues, however, remain
unresolved. Can
central black holes form in the absence of a bulge? And
does the mass
function of central black holes extend below 10^6 solar
masses?
Intermediate-mass black holes {<10^6 solar masses}, if
they exist, may
offer important clues to the nature of the seeds of
supermassive black
holes. Using the SDSS, our group has successfully uncovered
a new
population of AGNs with intermediate-mass black holes that
reside in
low-luminosity galaxies. However, very little is known
about the
detailed morphologies or structural parameters of the host
galaxies
themselves, including the crucial question of whether they
have bulges
or not. Surprisingly, the majority of the targets of our
Cycle 14 pilot
program have structural properties similar to dwarf
elliptical galaxies.
The statistics from this initial study, however, are
really too sparse
to reach definitive conclusions on this important new
class of black
holes. We wish to extend this study to a larger sample, by
using the
Snapshot mode to obtain WFPC2 F814W images from a parent
sample of 175
AGNs with intermediate- mass black holes selected from our
final SDSS
search. We are particularly keen to determine whether the
hosts contain
bulges, and if so, how the fundamental plane properties of
the host
depend on the mass of their central black holes. We will
also
investigate the environment of this unique class of AGNs.
WFPC2 11218
Snapshot Survey for Planetary Nebulae in Globular Clusters
of the Local
Group
Planetary nebulae {PNe} in globular clusters {GCs} raise a
number of
interesting issues related to stellar and galactic
evolution. The number
of PNe known in Milky Way GCs, 4, is surprisingly low if
one assumes
that all stars pass through a PN stage. However, it is
likely that the
remnants of stars now evolving in Galactic GCs leave the
AGB so slowly
that any ejected nebula dissipates long before the star
becomes hot
enough to ionize it. Thus there should not be ANY PNe in
Milky Way
GCs--but there are four! It has been suggested that these
PNe are the
result of mergers of binary stars within GCs, i.e., that
they are
descendants of blue stragglers. The frequency of
occurrence of PNe in
external galaxies poses more questions, because it shows a
range of
almost an order of magnitude. I propose a Snapshot survey
aimed at
discovering PNe in the GC systems of Local Group galaxies
more distant
than the Magellanic Clouds. These clusters, some of which
may be much
younger than their counterparts in the Milky Way, might
contain many
more PNe than those of our own galaxy. I will use the
standard technique
of emission-line and continuum imaging, which easily
discloses PNe.
WFPC2 11235
HST NICMOS Survey of the Nuclear Regions of Luminous
Infrared Galaxies
in the Local Universe
At luminosities above 10^11.4 L_sun, the space density of
far-infrared
selected galaxies exceeds that of optically selected
galaxies. These
`luminous infrared galaxies' {LIRGs} are primarily
interacting or
merging disk galaxies undergoing enhanced star formation
and Active
Galactic Nuclei {AGN} activity, possibly triggered as the
objects
transform into massive S0 and elliptical merger remnants.
We propose
NICMOS NIC2 imaging of the nuclear regions of a complete
sample of 88
L_IR > 10^11.4 L_sun luminous infrared galaxies in the
IRAS Revised
Bright Galaxy Sample {RBGS: i.e., 60 micron flux density
> 5.24 Jy}.
This sample is ideal not only in its completeness and
sample size, but
also in the proximity and brightness of the galaxies. The
superb
sensitivity and resolution of NICMOS NIC2 on HST enables a
unique
opportunity to study the detailed structure of the nuclear
regions,
where dust obscuration may mask star clusters, AGN and
additional nuclei
from optical view, with a resolution significantly higher
than possible
with Spitzer IRAC. This survey thus provides a crucial
component to our
study of the dynamics and evolution of IR galaxies
presently underway
with Wide-Field, HST ACS/WFC and Spitzer IRAC observations
of these 88
galaxies. Imaging will be done with the F160W filter
{H-band} to examine
as a function of both luminosity and merger stage {i} the
luminosity and
distribution of embedded star clusters, {ii} the presence
of optically
obscured AGN and nuclei, {iii} the correlation between the
distribution
of 1.6 micron emission and the mid-IR emission as detected
by Spitzer
IRAC, {iv} the evidence of bars or bridges that may funnel
fuel into the
nuclear region, and {v} the ages of star clusters for
which photometry
is available via ACS/WFC observations. The NICMOS data,
combined with
the HST ACS, Spitzer, and GALEX observations of this
sample, will result
in the most comprehensive study of merging and interacting
galaxies to
date.
WFPC2 11795
WFPC2 Cycle 16 UV Earth Flats
Monitor flat field stability. This proposal obtains
sequences of earth
streak flats to improve the quality of pipeline flat
fields for the
WFPC2 UV filter set. These Earth flats will complement the
UV earth flat
data obtained during cycles 8-15.
WFPC2 11797
Supplemental WFPC2 CYCLE 16 Intflat Linearity Check and
Filter Rotation
Anomaly Monitor
Supplemental observations to 11029, to cover period from
Aug 08 to SM4.
Intflat observations will be taken to provide a linearity
check: the
linearity test consists of a series of intflats in F555W,
in each gain
and each shutter. A combination of intflats, visflats, and
earthflats
will be used to check the repeatability of filter wheel
motions.
(Intflat sequences tied to decons, visits 1-18 in prop
10363, have been
moved to the cycle 15 decon proposal 11022 for easier
scheduling.)
Note: long-exposure WFPC2 intflats must be scheduled
during ACS anneals
to prevent stray light from the WFPC2 lamps from
contaminating long ACS
external exposures.
Note: These are supplemental observations to cover June to
SM4 (oct 8
'08) + 6 months.
WFPC2/NIC3/ACS/SBC 11144
Building on the Significant NICMOS Investment in GOODS: A
Bright,
Wide-Area Search for z>=7 Galaxies
One of the most exciting frontiers in observational
cosmology has been
to trace the buildup and evolution of galaxies from very
early times.
While hierarchical theory teaches us that the star
formation rate in
galaxies likely starts out small and builds up gradually,
only recently
has it been possible to see evidence for this
observationally through
the evolution of the LF from z~6 to z~3. Establishing that
this build up
occurs from even earlier times {z~7-8} has been difficult,
however, due
to the small size of current high-redshift z~7-8 samples
-- now
numbering in the range of ~4-10 sources. Expanding the
size of these
samples is absolutely essential, if we are to push current
studies of
galaxy buildup back to even earlier times. Fortunately, we
should soon
be able to do so, thanks to ~50 arcmin**2 of deep {26.9 AB
mag at 5
sigma} NICMOS 1.6 micron data that will be available over
the two ACS
GOODS fields as a result of one recent 180-orbit ACS
backup program and
a smaller program. These data will nearly triple the deep
near-IR
imaging currently available and represent a significant
resource for
finding and characterizing the brightest high-redshift
sources -- since
high-redshift candidates can be easily identified in these
data from
their red z-H colours. Unfortunately, the red z-H colours
of these
candidates are not sufficient to determine that these
sources are at
z>=7, and it is important also to have deep photometry
at 1.1 microns.
To obtain this crucial information, we propose to follow
up each of
these z-H dropouts with NICMOS at 1.1 microns to determine
which are at
high redshift and thus significantly expand our sample of
luminous, z>=7
galaxies. Since preliminary studies indicate that these
candidates occur
in only 30% of the NIC3 fields, our follow-up strategy is
~3 times as
efficient as without this preselection and 9 times as
efficient as a
search in a field with no pre- existing data. In total, we
expect to
identify ~8 luminous z-dropouts and possibly ~2 z~10 J-
dropouts as a
result of this program, more than tripling the number
currently known.
The increased sample sizes are important if we are to
solidify current
conclusions about galaxy buildup and the evolution of the
LF from z~8.
In addition to the high redshift science, these deep 1.1
micron data
would have significant value for many diverse endeavors,
including {1}
improving our constraints on the stellar mass density at
z~7-10 and {2}
doubling the number of galaxies at z~6 for which we can
estimate dust
obscuration.
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)
COMPLETED OPS NOTES: (None)
SCHEDULED
SUCCESSFUL
FGS GSacq
09
09
FGS REacq
05
05
OBAD with Maneuver
28
28
SIGNIFICANT EVENTS: (None)