Daily Report #4118
- From: Lynn Bassford <lbassford@xxxxxxxxxxxx>
- Date: Mon, 22 May 2006 15:24:10 +0000 (UTC)
HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science
DAILY REPORT # 4118
PERIOD COVERED: UT May 19,20,21, 2006 (DOY 139,140,141)
OBSERVATIONS SCHEDULED
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.
ACS/HRC 10991
Light Echoes from SN 2006X in M100
We propose a minimal investment of spacecraft time to discover and
confirm a light echo from Supernova 2006X in M100, the closest Type Ia
in many years. Our spectroscopic and photometric data indicate that
this SN sits behind a large amount of interstellar dust likely to
produce a strong echo signal. This is one of very few cases where we
will be able to study the three-dimensional environment of a SN Ia in
full detail, and begin to understand how environmental effects play
into the evolutionary and observational factors which influence the
utility of SN Ia as standard candles for probing cosmology. We propose
an efficient program to definitively detect {or not} a light echo of
reasonable signal strength, to confirm that it is an echo by
demonstrating apparent superluminal motion if it exists, to map the
three-dimensional geometry of the reflecting interstellar structures,
and to detail the reflectance properties of the dust which can be used
to constrain ! its grain size and composition distribution.
ACS/WFC 10775
An ACS Survey of Galactic Globular Clusters
We propose to conduct an ACS/WFC imaging survey of Galactic globular
clusters. We will construct the most extensive and deepest set of
photometry and astrometry to-date for these systems reaching a main
sequence mass of ~0.2 solar mass with S/N >= 10. We will combine these
data with archival WFPC2 and STIS images to determine proper motions
for the stars in our fields. The resultant cleaned cluster CMDs will
allow us to study a variety of scientific questions. These include
[but are not limited to] 1} the determination of cluster ages and
distances 2} the construction of main sequence mass functions and the
issue of mass segregation 3} the internal motions and dynamical
evolution of globular clusters, and 4} absolute cluster motions,
orbits, and the Milky Way gravitational potential. We anticipate that
the unique resource provided by the proposed treasury archive will
play a central role in the field of globular cluster studies for
decades, with a stature comparable to that of the Hubble Deep Field
for high redshift studies.
WFPC2 10767
Further Resolving the Puzzle of Hybrid Star X-rays
Do Alpha TrA {K2II} and Beta Ind {K1II} have previously unrecognized
X-ray active dwarf companions, leading us astray concerning the
coronal properties of the "hybrid-chromosphere" class? Establishing
the true X-ray luminosities of the hybrids is a basis for
understanding magnetic field generation in evolved supergiants, the
driving of their winds, and the seeding of coronal conditions in their
extended outer envelopes. It also bears on the issue of late-type
dwarfs orbiting main sequence B stars, the evolutionary predecessors
of K bright giants. We propose to directly image the putative hybrid
companions using Chandra, with supporting observations from HST/WFPC2.
ACS/HRC/WFC 10758
ACS CCDs daily monitor
This program consists of a set of basic tests to monitor, the read
noise, the development of hot pixels and test for any source of noise
in ACS CCD detectors. The files, biases and dark will be used to
create reference files for science calibration. This programme will be
for the entire lifetime of ACS. Changes from cycle 13:- The default
gain for WFC is 2 e-/DN. As before bias frames will be collected for
both gain 1 and gain 2. Dark frames are acquired using the default
gain {2}. This program cover the period May, 31 2006- Oct, 1-2006. The
first half of the program has a different proposal number: 10729.
ACS/WFC 10742
Ramp Filter and Grism Zeroth Order Wavelengths
A calibration of ramp filters on the ACS is obtained through crossing
the ramp filters with the G800L grism in observations of the standard
star GD 153. The standard star is also observed through the F606W
filter and each ramp crossed with a wide-band filter to measure any
filter- wedge offset from the standard grism calibration produced by
crossing a ramp with the grism. The ramp filters chosen for this first
calibration are those which have been used most extensively by
observers during the past ACS cycles and can be usefully crossed with
the G800L grism.
ACS/HRC 10738
Earth Flats
Sky flats will be obtained by observing the bright Earth with the HRC
and WFC. These observations will be used to verify the accuracy of the
flats currently in the pipeline and to monitor any changes. Weekly
coronagraphic monitoring is required to assess the changing position
of the spots.
ACS/WFC 10624
Solving the Mystery of the Short-Hard Gamma-Ray Bursts
Eight years after the afterglow detections that revolutionized studies
of the long-soft gamma-ray bursts, not even one afterglow of a
short-hard GRB has been seen, and the nature of these events has
become one of the most important problems in GRB research. The Swift
satellite, expected to be in full operation throughout Cycle 14, will
report few-arcsecond localizations for short-hard bursts in minutes,
enabling prompt, deep optical afterglow searches for the first time.
Discovery and observation of the first short-hard optical afterglows
will answer most of the critical questions about these events: What
are their distances and energies? Do they occur in distant galaxies,
and if so, in which regions of those galaxies? Are they the result of
collimated or quasi-spherical explosions? In combination with an
extensive rapid-response ground-based campaign, we propose to make the
critical high-sensitivity HST TOO observations that will allow us to
answer these questions. If theorists are correct in attributing the
short-hard bursts to binary neutron star coalescence events, then they
will serve as signposts to the primary targeted source population for
ground-based gravitational-wave detectors, and short-hard burst
studies will have a vital role to play in guiding those observations.
ACS/WFC 10587
Measuring the Mass Dependence of Early-Type Galaxy Structure
We propose two-color ACS-WFC Snapshot observations of a sample of 118
candidate early- type gravitational lens galaxies. Our lens-candidate
sample is selected to yield {in combination with earlier results} an
approximately uniform final distribution of 40 early-type strong
lenses across a wide range of masses, with velocity dispersions {a
dynamical proxy for mass} ranging from 125 to 300 km/s. The proposed
program will deliver the first significant sample of low-mass
gravitational lenses. All of our candidates have known lens and source
redshifts from Sloan Digital Sky Survey data, and all are bright
enough to permit detailed photometric and stellar- dynamical
observation. We will constrain the luminous and dark-matter mass
profiles of confirmed lenses using lensed-image geometry and
lens-galaxy structural/photometric measurements from HST imaging in
combination with dynamical measurements from spatially resolved
ground-based follow-up spectroscopy. Hence we will determine, in
unprecedented detail, the dependence of early-type galaxy mass
structure and mass-to-light ratio upon galaxy mass. These results will
allow us to directly test theoretical predictions for halo
concentration and star-formation efficiency as a function of mass and
for the existence of a cuspy inner dark- matter component, and will
illuminate the structural explanation behind the fundamental plane of
early-type galaxies. The lens-candidate selection and confirmation
strategy that we propose has been proven successful for high-mass
galaxies by our Cycle 13 Snapshot program {10174}. The program that we
propose here will produce a complementary and unprecedented lens
sample spanning a wide range of lens-galaxy masses.
ACS/HRC 10556
Neutral Gas at Redshift z=0.5
Damped Lyman-alpha systems {DLAs} are used to track the bulk of the
neutral hydrogen gas in the Universe. Prior to HST UV spectroscopy,
they could only be studied from the ground at redshifts z>1.65.
However, HST has now permitted us to discover 41 DLAs at z<1.65 in our
previous surveys. Followup studies of these systems are providing a
wealth of information about the evolution of the neutral gas phase
component of the Universe. But one problem is that these 41
low-redshift systems are spread over a wide range of redshifts
spanning nearly 70% of the age of the Universe. Consequently, past
surveys for low-redshift DLAs have not been able to offer very good
precision in any small redshift regime. Here we propose an ACS-HRC-
PR200L spectroscopic survey in the redshift interval z=[0.37, 0.7]
which we estimate will permit us to discover another 41 DLAs. This
will not only allow us to double the number of low-redshift DLAs, but
it will also provide a relatively high-precision regime in the
low-redshift Universe that can be used to anchor evolutionary studies.
Fortunately DLAs have high absorption equivalent width, so
ACS-HRC-PR200L has high-enough resoultion to perform this proposed
MgII-selected DLA survey.
ACS/WFC 10551
Gamma-Ray Bursts from Start to Finish: A Legacy Approach
The progenitors of long-duration GRBs are now known to be massive
stars. This result lends credence to the collapsar model, where a
rotating massive star ends its life leaving a black hole or a highly
magnetized neutron star, and confirms its essential aspects. The focus
of attention now is on the black hole or magnetar engines that power
the bursts. Somehow these engines create the most highly relativistic
and highly collimated outflows that we know of, through mechanisms
that no current theory can explain. These astrophysical laboratories
challenge our understanding of relativistic shocks, of mechanisms for
extracting energy from a black hole, and of how physics works in
extreme conditions. The launch of Swift is bringing us into a new era,
where we can make broadband observations that will enable us to study
these fascinating physical processes. We propose here an ambitious,
comprehensive program to obtain the datasets that will become the
standard that any successful model for the central engine must
explain. This programs leverages the HST observations to the maximum
extent by our commitment of Swift observations, a Large program at the
VLA, and extensive ground-based optical resources. By studying the
engines and searching for jets in a variety of events, this program
will investigate the conditions necessary for the engine and jet
formation itself.
NIC2/ACS/WFC/WFPC2 10532
Kinematics and morphology of the most massive field disk galaxies at
z>1
We propose to obtain 1 orbit NIC-2 images of a sample of the 15 most
massive galaxies found at $1 < z < 1.3$. These were culled from over
20, 000 Keck spectra collected as part of DEEP and are unique among
high redshift massive galaxy samples in being kinematically selected.
We intend to test whether these potentially very young galaxies are
likely precursors to massive local disks, assuming no further merging.
NIC-2 images provide rest-frame optical morphologies that will show
whether they are normal disky systems or instead more disturbed
looking objects with multiple subcomponents, mergers, peculiar
structure, etc. NIC-2 provides near-IR resolutions sufficient to
enable measurements of bulges and disks subcomponents. The near-IR
will fill a critical gap in the broad-band SED photometry of the
galaxy and its subcomponents to estimate mean stellar ages and stellar
masses and to assess whether old stellar bulges and disks are in place
at that time. Finally, this sample will yield the first statistically
significant results on the $z > 1$ evolution of the Tully-Fisher
relation for massive galaxies. In addition, we propose parallel
observations with ACS WFC {V and I bands} and WFPC2 {I-band}. These
will target up to 700 galaxies at redshifts 0.7 ... 1.2 for which the
DEEP2 survey has obtained precision redshifts and high-resolution
kinematic data. The added HST morphology and color information will
allow a variety of detailed studies on dynamical, structural, and
photometric evolution of galaxies.
ACS/HRC 10525
Characterizing the Near-UV Environment of M Dwarfs: Implications for
Extrasolar Planetary Searches and Astrobiology
We propose SNAP observations with the ACS HRC PR200L prism, designed
to measure the near ultraviolet emission in a sample of 107 nearby M
dwarfs. The sample spans the mass range from 0.1 - 0.6 solar masses
{temperature range 2200K - 4000K} where the UV energy distributions
vary widely between active and inactive stars. The strength and
distribution of this UV emission can have critical consequences for
the atmospheres of attendant planets. Our proposed observations will
provide desperately needed constraints on models of the habitability
zone and the atmospheres of possible terrestrial planets orbiting M
dwarf hosts, and will be used to sharpen TPF target selection. In
addition, the NUV data will be used in conjunction with existing
optical, FUV and X-ray data to constrain a new generation of M dwarf
atmospheric models, and to explore unanswered questions regarding the
dynamo generation and magnetic heating in these low-mass stars.
ACS/WFC 10523
The Halo Shape and Metallicity of Massive Spiral Galaxies
We propose to resolve the stellar populations of the halos of seven
nearby, massive disk galaxies using a SNAP survey with WFC/ACS. These
observations will provide star counts and color-magnitude diagrams 2-3
magnitudes below the tip of the Red Giant Branch along the two
principal axes and one intermediate axis of each galaxy. We will
measure the metallicity distribution functions and stellar density
profiles from star counts down to very low average surface
brightnesses, equivalent to ~31 V-mag per square arcsec. This proposal
will create a unique sampling of galaxy halo properties, as our
targets cover a range in galaxy mass, luminosity, inclination, and
morphology. As function of these galaxy properties this survey will
provide:- the first systematic measurement of radial light profiles
and axial ratios of the diffuse stellar halos and outer disks of
spiral galaxies- a comprehensive analysis of halo metallicity
distributions as function of galaxy type and position within the
galaxy- an unprecedented study of the stellar metallicity and age
distribution in the outer disk regions where the disk truncations
occur- the first comparative study of globular clusters and their
field stellar populations We will use these fossil records of the
galaxy assembly process to test halo formation models within the
hierarchical galaxy formation scheme.
ACS/HRC 10512
Search for Binaries Among Faint Jupiter Trojan Asteroids
We propose an ambitious SNAPSHOT program to survey faint Jupiter
Trojan asteroids for binary companions. We target 150 objects, with
the expectation of acquiring data on about 50%. These objects span
Vmag = 17.5-19.5, a range inaccessible with ground-based adaptive
optics. We now have a significant sample from our survey of brighter
Trojans to suggest that the binary fraction is similar to that which
we find among brighter main-belt asteroids, roughly 2%. However, our
observations suggest a higher binary fraction for smaller main-belt
asteroids, probably the result of a different formation mechanism
{evident also from the physical characteristics of the binaries}.
Because the collision environment among the Trojans is similar to that
of the Main Belt, while the composition is likely to be very
different, sampling the binary fraction among the fainter Trojans
should help us understand the collisional and binary formation
mechanisms at work in various populations, including the Kuiper Belt,
and help us evaluate theories for the origin of the Trojans.
Calibration of and constraints on models of binary production and
collisional evolution can only be done using these large-scale,
real-life physical systems that we are beginning now to find and
utilize.
ACS/WFC 10496
Decelerating and Dustfree: Efficient Dark Energy Studies with
Supernovae and Clusters
We propose a novel HST approach to obtain a dramatically more useful
"dust free" Type Ia supernovae {SNe Ia} dataset than available with
the previous GOODS searches. Moreover, this approach provides a
strikingly more efficient search-and-follow-up that is primarily pre-
scheduled. The resulting dark energy measurements do not share the
major systematic uncertainty at these redshifts, that of the
extinction correction with a prior. By targeting massive galaxy
clusters at z > 1 we obtain a five-times higher efficiency in
detection of Type Ia supernovae in ellipticals, providing a
well-understood host galaxy environment. These same deep cluster
images then also yield fundamental calibrations required for future
weak lensing and Sunyaev-Zel'dovich measurements of dark energy, as
well as an entire program of cluster studies. The data will make
possible a factor of two improvement on supernova constraints on dark
energy time variation, and much larger improvement in systematic
uncertainty. They will provide both a cluster dataset and a SN Ia
dataset that will be a longstanding scientific resource.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are preliminary
reports of potential non-nominal performance that will be
investigated.)
HSTARS:
#10269- REacq(2,1,2) failed due to search radius limit exceeded @140/0803z.
The REacq(2,1,2) scheduled at 140/07:58:17 failed at 08:02:52 due to
search radius limit exceeded on FGS 2. The map at 08:05:36 showed
errors of V1=-3.20, V2=88.50, V3=-10.61, and RSS=89.19. Obs affected:
ACS 215-222. ESB message "a05" (FGS Coarse Track failed - Search
Radius Limit exceeded) was received
#10270- GSAcq(1,3,3) failed to RGA control @140/1818z.
GSAcq scheduled at 140/18:15:34-18:22:31 failed to RGA control due to
stop flag (QF1STOPF) on FGS-1. Prior OBAD's were successful with (RSS)
error corrections of 3359.43 and 18.08, respectively. No MAP is
scheduled prior to the next set of OBAD's. Possible observations
effected: ACS 13-16
#10271- GSAcq (2,1,1) failed to RGA control @141/12:05z.
At AOS 141/12:05:33 GSAcq (2,1,1) scheduled for 141/11:09:36-11:17:00
was observed to have failed to RGA control, displaying mnemonics
QFSTOPF & QSTOP. Pre and Post-acquisition OBADs and MAP attitude error
correction not avaliable due to LOS. Possible obs effected: ACS 57 .
#10272- OBAD Failed Identification (ESB 1902)@ 141/17:15z.
At AOS 141/17:15:37, OBAD2 observed to have failed. A 486 ESB message
1902 (OBAD Failed Identification) was received. OBAD2 had (RSS) value
of 46588.78 arcseconds. Per OPS REQUEST 17543-2, OBAD tables 369 and
370 were dumped at 141/17:33:58 and 17:36:14 respectively. GSAcq at
141/17:34:23 was successful.
COMPLETED OPS REQUEST:
#17543-2 - Dump OBAD Tables after failed OBAD @141/1737z
COMPLETED OPS NOTES: (None)
SCHEDULED SUCCESSFUL FAILURE TIMES
FGS GSacq 23 21 (HSTAR 10270 & 10271)
FGS REacq 22 21 (HSTAR 10269)
OBAD with Maneuver 70 69 (HSTAR 10272)
SIGNIFICANT EVENTS: (None)
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