HUBBLE
SPACE TELESCOPE - Continuing to collect World Class Science
DAILY
REPORT # 4534
PERIOD
COVERED: UT January 25,26,27, 2007 (DOY 025,026,027)
OBSERVATIONS
SCHEDULED
NIC1/NIC2/NIC3
8795
NICMOS Post-SAA calibration - CR Persistence Part 6
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 i
mages.
Each observation will need its own CRMAP, as different SAA
passages
leave different imprints on the NICMOS detectors.
WFPC2
11289
SL2S:
The Strong Lensing Legacy Survey
Recent
systematic surveys of strong galaxy-galaxy lenses {CLASS, SLACS,
GOODS,
etc.} are producing spectacular results for galaxy masses roughly
below
a transition mass M~10^13 Mo. The observed lens properties and
their
evolution up to z~0.2, consistent with numerical simulations, can
be
described by isothermal elliptical potentials. In contrast, modeling
of
giant arcs in X-ray luminous clusters {halo masses M >~10^13 Mo}
favors
NFW mass profiles, suggesting that dark matter halos are not
significantly
affected by baryon cooling. Until recently, lensing
surveys
were neither deep nor extended enough to probe the intermediate
mass
density regime, which is fundamental for understanding the assembly
of
structures. The CFHT Legacy Survey now covers 125 square degrees, and
thus
offers a large reservoir of strong lenses probing a large range of
mass
densities up to z~1. We have extracted a list of 150 strong lenses
using
the most recent CFHTLS data release via automated procedures.
Following
our first SNAPSHOT proposal in cycle 15, we propose to
continue
the Hubble follow-up targeting a larger list of 130 lensing
candidates.
These are intermediate mass range candidates {between
galaxies
and clusters} that are selected in the redshift range of 0.2-1
with
no a priori X-ray selection. The HST resolution is necessary for
confirming
the lensing candidates, accurate modeling of the lenses, and
probing
the total mass concentration in galaxy groups up to z~1 with the
largest
unbiased sample available to date.
NIC3
11236
Did
Rare, Large Escape-Fraction Galaxies Reionize the Universe?
Lyman
continuum photons produced in massive starbursts may have played a
dominant
role in the reionization of the Universe. Starbursts are
important
contributors to the ionizing metagalactic background at lower
redshifts
as well. However, their contribution to the background depends
upon
the fraction of ionizing radiation that escapes from the intrinsic
opacity
of galaxies below the Lyman limit. Current surveys suggest that
the
escape fraction is close to zero in most galaxies, even among young
starbursts,
but is large in 15-25% of them. Non-uniform escape fractions
are
expected as a result of violent events creating clear paths in small
parts
of galaxies. The number of galaxies observed with high escape
fraction
will result from the combination of the intrinsic number with
clear
lines of sight and their orientation with respect to the observer.
We
propose to measure the fraction of escaping Lyman continuum radiation
in
a large sample (47) of z~0.7 starbursts in the COSMOS field. These
compact
UV-lumnious galaxies are good analogs to high redshift LBGs.
Using
the SBC/PR130L we can quickly (1-4 orbits) detect relative escape
fractions
(f_LC/f_1500) of 25% or more. This will be the first
measurement
of the escape fraction in sources between z=1 and the local
universe.
We expect ~10 detections. Stacking will set limits of <4% on
the
relative escape fraction in the rest. We will correlate the LC
detections
with the properties of the galaxies. By targetting z~0.7 in
COSMOS,
we will have tremendous ancillary information on those sources.
A
non-detection in all sources would be significant (99% confidence).
This
would imply that QSOs provide the overwhelming majority of ionizing
radtion
at z<1, requiring substantial evolution in the processes within
Lyman
break galaxies which allow large escape fractions at high
redshift.
ACS/SBC
11220
Mapping
the FUV Evolution of Type IIn Supernovae
We
will use the PR110L prism on the SBC of ACS to map the FUV evolution
of
Type IIn supernovae {SNe}. The main goal of this proposal is to
measure
the FUV continuum, Ly-a emission line flux, and their evolution
to
{1} quantify and interpret Type IIn SN transient event detections at
high
redshift and {2} dramatically improve current high redshift Type
IIn
selection criteria. We show that the inherent properties of Type IIn
SNe
facilitate high redshift detection. We will observe the rest-frame
FUV
of a sample of eight 0.02 < z < 0.33 Type IIn SNe to directly
measure
the survival of Ly-alpha photons in low to intermediate redshift
Type
IIn SNe environments and extrapolate the results to high redshift.
We
will calibrate relationships such as FUV luminosity vs. emission line
flux
and measure emission line evolution vs. FUV light evolution. The
intent
is to categorize and improve the utility of Type IIn SNe.
FGS
11211
An
Astrometric Calibration of Population II Distance Indicators
In
2002 HST produced a highly precise parallax for RR Lyrae. That
measurement
resulted in an absolute magnitude, M{V}= 0.61+/-0.11, a
useful
result, judged by the over ten refereed citations each year
since.
It is, however, unsatisfactory to have the direct,
parallax-based,
distance scale of Population II variables based on a
single
star. We propose, therefore, to obtain the parallaxes of four
additional
RR Lyrae stars and two Population II Cepheids, or
stars.
The Population II Cepheids lie with the RR Lyrae stars on a
common
K-band Period-Luminosity relation. Using these parallaxes to
inform
that relationship, we anticipate a zero-point error of 0.04
magnitude.
This result should greatly strengthen confidence in the
Population
II distance scale and increase our understanding of RR Lyrae
star
and Pop II Cepheid astrophysics.
FGS
11210
The
Architecture of Exoplanetary Systems
Are
all planetary systems coplanar? Concordance cosmogony makes that
prediction.
It is, however, a prediction of extrasolar planetary system
architecture
as yet untested by direct observation for main sequence
stars
other than the Sun. To provide such a test, we propose to carry
out
FGS astrometric studies on four stars hosting seven companions. Our
understanding
of the planet formation process will grow as we match not
only
system architecture, but formed planet mass and true distance from
the
primary with host star characteristics for a wide variety of host
stars
and exoplanet masses. We propose that a series of FGS astrometric
observations
with demonstrated 1 millisecond of arc per-observation
precision
can establish the degree of coplanarity and component true
masses
for four extrasolar systems: HD 202206 {brown dwarf+planet}; HD
128311
{planet+planet}, HD 160691 = mu Arae {planet+planet}, and HD
222404AB
= gamma Cephei {planet+star}. In each case the companion is
identified
as such by assuming that the minimum mass is the actual mass.
For
the last target, a known stellar binary system, the companion orbit
is
stable only if coplanar with the AB binary orbit.
WFPC2
11202
The
Structure of Early-type Galaxies: 0.1-100 Effective Radii
The
structure, formation and evolution of early-type galaxies is still
largely
an open problem in cosmology: how does the Universe evolve from
large
linear scales dominated by dark matter to the highly non-linear
scales
of galaxies, where baryons and dark matter both play important,
interacting,
roles? To understand the complex physical processes
involved
in their formation scenario, and why they have the tight
scaling
relations that we observe today {e.g. the Fundamental Plane}, it
is
critically important not only to understand their stellar structure,
but
also their dark-matter distribution from the smallest to the largest
scales.
Over the last three years the SLACS collaboration has developed
a
toolbox to tackle these issues in a unique and encompassing way by
combining
new non-parametric strong lensing techniques, stellar
dynamics,
and most recently weak gravitational lensing, with
high-quality
Hubble Space Telescope imaging and VLT/Keck spectroscopic
data
of early-type lens systems. This allows us to break degeneracies
that
are inherent to each of these techniques separately and probe the
mass
structure of early-type galaxies from 0.1 to 100 effective radii.
The
large dynamic range to which lensing is sensitive allows us both to
probe
the clumpy substructure of these galaxies, as well as their
low-density
outer haloes. These methods have convincingly been
demonstrated,
by our team, using smaller pilot-samples of SLACS lens
systems
with HST data. In this proposal, we request observing time with
WFPC2
and NICMOS to observe 53 strong lens systems from SLACS, to obtain
complete
multi-color imaging for each system. This would bring the total
number
of SLACS lens systems to 87 with completed HST imaging and
effectively
doubles the known number of galaxy-scale strong lenses. The
deep
HST images enable us to fully exploit our new techniques, beat down
low-number
statistics, and probe the structure and evolution of
early-type
galaxies, not only with a uniform data-set an order of
magnitude
larger than what is available now, but also with a fully
coherent
and self-consistent methodological approach!
S/C
11163
Accreting
Pulsating White Dwarfs in Cataclysmic Variables
Recent
ground-based observations have increased the number of known
pulsating
white dwarfs in close binaries with active mass transfer
{cataclysmic
variables} from 5 to 11 systems. Our past Cycles 8 and 11
STIS
observations of the first 2 known, followed by our Cycle 13 SBC
observations
of the next 3 discovered, revealed the clear presence of
the
white dwarf and increased amplitude of the pulsations in the UV
compared
to the optical. The temperatures derived from the UV spectra
show
4 systems are much hotter than non-interacting pulsating white
dwarfs.
A larger sample is needed to sort out the nature of the
instability
strip in accreting pulsators i.e. whether effects of
composition
and rotation due to accretion result in a well- defined
instability
strip as a function of Teff.
NIC2/WFPC2
11142
Revealing
the Physical Nature of Infrared Luminous Galaxies at 0.3
We
aim to determine physical properties of IR luminous galaxies at
0.3<z<2.7
by requesting coordinated HST/NIC2 and MIPS 70um observations
of
a unique, 24um flux-limited sample with complete Spitzer mid-IR
spectroscopy.
The 150 sources investigated in this program have S{24um}
>
0.8mJy and their mid-IR spectra have already provided the majority
targets
with spectroscopic redshifts {0.3<z<2.7}. The proposed
150~orbits
of NIC2 and 66~hours of MIPS 70um will provide the physical
measurements
of the light distribution at the rest-frame ~8000A and
better
estimates of the bolometric luminosity. Combining these
parameters
together with the rich suite of spectral diagnostics from the
mid-IR
spectra, we will {1} measure how common mergers are among LIRGs
and
ULIRGs at 0.3<z<2.7, and establish if major mergers are the drivers
of
z>1 ULIRGs, as in the local Universe. {2} study the co-evolution of
star
formation and blackhole accretion by investigating the relations
between
the fraction of starburst/AGN measured from mid-IR spectra vs.
HST
morphologies, L{bol} and z. {3} obtain the current best estimates of
the
far-IR emission, thus L{bol} for this sample, and establish if the
relative
contribution of mid-to-far IR dust emission is correlated with
morphology
{resolved vs. unresolved}.
WFPC2
11077
HST/WFPC2
1-gyro On-orbit Checkout
The
goal of this program is to verify the performance of the HST under
One
Gyro operation.
As
in previous Two Gyro Testing and Orbital Verification programs the
analysis
will be done by characterizing the Point Spread Function
(PSF)
of PC1 in the F555W filter.
Two
Primary issues addressed by this proposal: - PSF structure and
repeatibility
- Pointing, stability, and offset accuracy.
PSF
will be characterized as a function of - exposure time - guide star
brightness
- sky position
For
the Pointing we will characterize: - repeatability of small offsets
-
stability within visibility period - stability across occultations. as
a
function of the guide star brightness
The
Program requires fifteen orbits: (7 for the main target, 1 for the
secondary
target) for two gyro mode, then for 1-gyro mode. The structure
of
the visits is identical to the visits executed as part of the program
10458
"ACS and WFPC2 T
with
the only exception of the NICMOS parallel that have been removed.
The
target selection is based on the visibility in the mid January to
mid
February 2008 timeframe. Final target selection will be confirmed
after
the analysis of the guide star availability.
WFPC2
11038
Narrow
Band and Ramp Filter Closeout
These
observations are to improve calibration of narrow band and ramp
filters.
We also test for changes in the filter properties during
WFPC2's
14 years on-board HST.
WFPC2
11032
CTE
Extended Targets Closeout
Measuring
the charge transfer efficiency {CTE} of an astronomical CCD
camera
is crucial to determining the CCD's photometric fidelity across
the
field of view. WFPC2's CTE has degraded steadily over the last 13
years
because of continuous exposure to trapped particles in HST's
radiation
environment. The fraction of photometric signal lost from
WFPC2's
CTI {change transfer inefficiency} is a function of WFPC2's time
in
orbit, the integrated signal in the image, the location of the image
on
the CCD, and the background signal. Routine monitoring of WFPC2's
degrading
CTE over the last 13 years has primarily concerned the effects
of
CTI on point-source photometry. However, most of the sources imaged
by
WFPC2 are extended rather than point- like. This program aims to
characterize
the effects of CTI on the photometry and morphology of
extended
sources near the end of WFPC2's functional life. Images of a
standard
field within the rich galaxy cluster Abell 1689 are recorded
with
each WFPC2 camera using the F606W and F814W filters. These images
will
be compared with contemporaneous images of Abell 1689 recorded with
the
field rotated by approximately 180 degrees to assess differences
between
extended sources imaged near and far from the serial register.
The
images will also be compared with similar images recorded in Cycle 8
{Program
8456} to characterize the rate of CTE degradation over the
lifetime
of WFPC2.
WFPC2
10905
The
Dynamic State of the Dwarf Galaxy Rich Canes Venatici I Region
With
accurate distances, the nearest groups of galaxies can be resolved
in
3 dimensions and the radial component of the motions of galaxies due
to
local density perturbations can be distinguished from cosmological
expansion
components. Currently, with the ACS, galaxy distances within 8
Mpc
can be measured effectively and efficiently by detecting the tip of
the
red giant branch {TRGB}. Of four principal groups at high galactic
latitude
in this domain, the Canes Venatici I Group {a} is the least
studied,
{b} is the most populated, though overwhelmingly by dwarf
galaxies,
and {c} is likely the least dynamically evolved. It is
speculated
that galaxies in low mass groups may fail to retain baryons
as
effectively as those in high mass groups, resulting in significantly
higher
mass-to-light ratios. The CVn I Group is suspected to lie in the
mass
regime where the speculated astrophysical processes that affect
baryon
retention are becoming important.
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 23 23
FGS
REacq 19 19
OBAD
with Maneuver 84 84
SIGNIFICANT
EVENTS: (None)