Daily #3981
- From: Joe Cooper <jcooper@xxxxxxxxxxxx>
- Date: Tue, 8 Nov 2005 15:40:16 +0000 (UTC)
HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science
DAILY REPORT # 3981
PERIOD COVERED: UT November 03, 2005 (DOY 307)
OBSERVATIONS SCHEDULED
ACS/HRC/WFC 10733
CCD Hot Pixel Annealing
Hot pixel annealing will continue to be performed once every 4 weeks.
The CCD TECs will be turned off and heaters will be activated to bring
the detector temperatures to about +20C. This state will be held for
approximately 6 hours, after which the heaters are turned off, the TECs
turned on, and the CCDs returned to normal operating condition. To
assess the effectiveness of the annealing, a bias and four dark images
will be taken before and after the annealing procedure for both WFC and
HRC. The HRC darks are taken in parallel with the WFC darks. The charge
transfer efficiency {CTE} of the ACS CCD detectors declines as damage
due to on-orbit radiation exposure accumulates. This degradation has
been closely monitored at regular intervals, because it is likely to
determine the useful lifetime of the CCDs. We combine the annealling
activity with the charge transfer efficiency monitoring and also merge
into the routine dark image collection. To this end, the CTE monitoring
exposures have been moved into this proposal . All the data for this
program is acquired using internal targets {lamps} only, so all of the
exposures should be taken during Earth occultation time {but not during
SAA passages}. This program emulates the ACS pre-flight ground
calibration and post-launch SMOV testing {program 8948}, so that results
from each epoch can be directly compared. Extended Pixel Edge Response
{EPER} and First Pixel Response {FPR} data will be obtained over a range
of signal levels for both the Wide Field Channel {WFC}, and the High
Resolution Channel {HRC}.
ACS/SBC 10739
Internal Flat Field Stability
The stability of the CCD flat fields will be monitored using the
calibration lamps and a sub-sample of the filter set. For the SBC
imaging filters, differences in the low-frequency flat field structure
with wavelength will be assessed. New high signal P-flats will be
obtained for the SBC prisms.
ACS/WFC 10592
An ACS Survey of a Complete Sample 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
ACS/WFC imaging 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, resolution, and field of view
of ACS/WFC on HST enables a unique opportunity to study the detailed
structure of galaxies that sample all stages of the merger process.
Imaging will be done with the F439W and F814W filters {B and I-band} to
examine as a function of both luminosity and merger state {i} the
evidence at optical wavelengths of star formation and AGN activity and
the manner in which instabilities {bars and bridges} in the galaxies may
funnel material to these active regions, {ii} the relationship between
star formation and AGN activity, and {iii} the structural properties
{AGN, bulge, and disk components} and fundamental parameters {effective
radius and surface brightness} of LIRGs and their similarity with
putative evolutionary byproducts {elliptical, S0 and classical AGN host
galaxies}. This HST survey will also bridge the wavelength gap between a
Spitzer imaging survey {covering seven bands in the 3.6-160 micron
range} and a GALEX UV imaging survey of these galaxies, but will resolve
complexes of star clusters and multiple nuclei at resolutions well
beyond the capabilities of either Spitzer or GALEX. The combined
datasets will result in the most comprehensive multiwavelength study of
interacting and merging galaxies to date.
ACS/WFC 10596
AGNs with Intermediate-mass Black Holes: A Test of the Black Hole-Bulge
Paradigm
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 {10^4-10^6 solar masses}, if they exist,
may offer important clues to the nature of the seeds of supermassive
black holes. In a first systematic search using the Sloan Digital Sky
Survey, we have recently discovered 19 Type 1 AGNs with candidate
intermediate-mass black holes that reside in low-luminosity, presumably
late-type host galaxies. Follow-up observations with Keck indicate that
these objects obey the low-mass extension of the well-known correlation
between black hole mass and bulge stellar velocity dispersion. However,
very little is known about the host galaxies themselves, including the
crucial question of whether they have bulges or not. We propose to
obtain ACS/WFC images of this unique sample of AGNs in order to
investigate the detailed structural properties of the host galaxies. We
are particularly keen to determine whether the hosts contain bulges, and
if so, where they lie on the fundamental plane of spheroids compared to
the bulges of supermassive black holes. We will also be able to measure
an accurate optical luminosity for the AGN, which is an essential
ingredient to improve the current mass estimates.
ACS/WFC/HRC 10536
What Are Stalled Preplanetary Nebulae? An ACS SNAPshot Survey
Essentially all planetary nebulae {PNs} are aspherical, whereas the
mass-loss envelopes of AGB stars are strikingly spherical. Our previous
SNAPshot surveys of a morphologically unbiased sample of pre-planetary
nebulae {PPNs} -- objects in transition between the AGB and PN
evolutionary phases -- show that roughly half our observed targets are
resolved, with bipolar or multipolar morphologies. Spectroscopic
observations of our sample confirm that these objects have not yet
evolved into planetary nebulae. Thus, the transformation from spherical
to aspherical geometries has already fully developed by the time these
dying stars have become PPNs. Although our current studies have yielded
exciting results, they are limited in two important ways -- {1} the
number of well-resolved objects is still small {18}, and the variety of
morphologies observed relatively multitudinous, hence no clear trends
can yet be established between morphology and other source properties
{e.g., near-IR, far-IR colors, stellar spectral type, envelope mass},
and {2} the current samples are strongly biased towards small PPNs, as
inferred from their low 60-to-25 micron flux ratios [R{60/25}<1].
However, the prototype of objects with R{60/25}>1, the Frosty Leo
Nebula, has a puzzlingly large post-AGB age {almost 10^4 yr} and a
fairly cool central star, very different from the expectations of
single-star stellar evolutionary models. A proposed, but still
speculative, hypothesis for such objects is that the slow evolution of
the central star is due to backflow of material onto the mass-losing
star, retarding its evolution towards the PN phase. This hypothesis has
significant consequences for both stellar and nebular evolution. We
therefore propose a survey of PPNs with R{60/25}>1 which is heavily
weighted towards the discovery of such "stalled PPNs". Supporting
kinematic observations using long-slit optical spectroscopy {with the
Keck}, millimeter and radio interferometric observations {with OVRO, VLA
& VLBA} are being undertaken. The results from this survey {together
with our previous work} will allow us to draw general conclusions about
the complex mass-outflow processes affecting late stellar evolution, and
will provide crucial input for theories of post-AGB stellar evolution.
Our survey will produce an archival legacy of long-standing value for
future studies of dying stars.
ACS/WFC/NIC2 10189
PANS-Probing Acceleration Now with Supernovae
Type Ia supernovae {SNe Ia} provide the most direct evidence for an
accelerating Universe, a result widely attributed to dark energy. Using
HST in Cycle 11 we extended the Hubble diagram with 6 of the 7
highest-redshift SNe Ia known, all at z>1.25, providing conclusive
evidence of an earlier epoch of cosmic deceleration. The full sample of
16 new SNe Ia match the cosmic concordance model and are inconsistent
with a simple model of evolution or dust as alternatives to dark energy.
Understanding dark energy may be the biggest current challenge to
cosmology and particle physics. To understand the nature of dark energy,
we seek to measure its two most fundamental properties: its evolution
{i.e., dw/dz}, and its recent equation of state {i.e., w{z=0}}. SNe Ia
at z>1, beyond the reach of the ground but squarely within the reach of
HST with ACS, are crucial to break the degeneracy in the measurements of
these two basic aspects of dark energy. The SNe Ia we have discovered
and measured with HST in Cycle 11, now double the precision of our
knowledge of both properties. Here we propose to quadruple the sample of
SNe Ia at z>1 in the next two cycles, complementing on-going surveys
from the ground at z<1, and again doubling the precision of dark energy
constraints. Should the current best fit model prove to be the correct
one, the precision expected from the current proposal will suffice to
rule out a cosmological constant at the 99% confidence level. Whatever
the result, these objects will provide the basis with which to extend
our empirical knowledge of this newly discovered and dominant component
of the Universe, and will remain one of the most significant legacies of
HST. In addition, our survey and follow-up data will greatly enhance the
value of the archival data within the target Treasury fields for galaxy
studies.
FGS 10613
Calibrating the Mass-Luminosity Relation at the End of the Main Sequence
We propose to use HST-FGS1R to calibrate the mass-luminosity relation
{MLR} for stars less massive than 0.2 Msun, with special emphasis on
objects near the stellar/brown dwarf border. Our goals are to determine
M_V values to 0.05 magnitude, masses to 5 than double the number of
objects with masses determined to be less than 0.20 Msun. This program
uses the combination of HST-FGS3/FGS1R at optical wavelengths and
ground-based infrared interferometry to examine nearby, subarcsecond
binary systems. The high precision measurements with HST-FGS3/FGS1R {to
1 mas in the separations} for these faint targets {V = 10--15} simply
cannot be equaled by any ground based technique. As a result of these
measurements, we are deriving high quality luminosities and masses for
the components in the observed systems, and characterizing their
spectral energy distributions from 0.5 to 2.2 Mum. Several of the
objects included have M < 0.1 Msun, placing them at the very end of the
stellar main sequence. Three of the targets are brown dwarf candidates,
including the current low mass record holder, GJ 1245C, with a mass of
0.062 +/- 0.004 Msun. The payoff of this proposal is high because all 10
of the systems selected have already been resolved with HST- FGS3/FGS1R
during Cycles 5--10 and contain most of the reddest objects for which
masses can be determined.
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 z<0.3 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 10513
The very late phases of a thermonuclear supernova
A better understanding of the physics of Type Ia supernovae {SNe} is
important for their use as cosmological standard candles. Late time
observations of the SN light curves are poorly studied - but offers a
unique way to probe the explosion models. Combining state of the art
models of 3- D explosions with sophisticated spectral modeling, we can
test these models against observations in a way not earlier possible. In
particular, the broad band light curves are sensitive to the degree of
clumping and the timing of the `infra-red catastrophe', factors which
depend on the explosion mechanism {deflagration vs. delayed detonation}.
Further, these observations can probe the degree of positron trapping in
the ejecta, important for both the SN ejecta and for the production of
free positrons in the galaxy. Because of its small distance, favorable
galaxy location and excellent ground based follow-up - SN 2003hv offers
a unique opportunity to obtain the best late light curves to date.
Observations in several optical and IR bands will enable us to
distinguish between different model predictions.
WFPC2 10751
WFPC2 CYCLE 14 Intflat Linearity Check and Filter Rotation Anomaly
Monitor
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 14 decon proposal 10744 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.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are preliminary reports
of potential non-nominal performance that will be investigated.)
HSTARS:
10003 - Gsacq(2,1,2) Failed due to Search Radius Exceeded on FGS 1 @308/0445z
GSacq(2,1,2)scheduled at 308/04:41:18 - 04:48:34 failed due to Search
Radius Limit Exceeded on FGS 1.
OBAD1 showed errors of:V1=-2473.11, V2=-32.55, V3=1092.71, RSS=2703.95
OBAD2 showed errors of: V1=-10.9, V2=1.61, V3=-2.68, RSS=3.31
The Map at 04:48:34 showed errors of: V1=3.08, V2=10.60, V3=3.57,
RSS=11.60
COMPLETED OPS REQUEST: (None)
COMPLETED OPS NOTES: (None)
SCHEDULED SUCCESSFUL FAILURE TIMES
FGS GSacq 08 07 308/0445z (HSTAR 10003)
FGS REacq 06 06
OBAD with Maneuver 20 20
SIGNIFICANT EVENTS: (None)
.
- Prev by Date: Daily #3980
- Next by Date: Daily #3982
- Previous by thread: Daily #3980
- Next by thread: Daily #3982
- Index(es):
Relevant Pages
|
