HST Daily Report # 3313
DAILY REPORT # 3313
PERIOD COVERED: DOY 64
OBSERVATIONS SCHEDULED
WF/PC-2 8669
Merger-Driven Evolution Of Galactic Nuclei: Observations Of The Toomre
Sequence.
The WF/PC-2 was used to observe galaxy mergers that are believed
responsible for
triggering starburst and AGN activity in galaxies, and even perhaps
transforming
spiral galaxies into ellipticals.
NICMOS 8791
NICMOS Post-SAA calibration – CR Persistence Part 2
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 9352
The Deceleration Test from Treasury Type Ia Supernovae at Redshifts 1.2 to
1.6
Type Ia supernovae {SNe Ia} provide the only direct evidence for an
accelerating
universe, an extraordinary result that needs a rigorous test. The case for
cosmic acceleration rests on the observation that SNe Ia at z ~ 0.5 are ~
0.25
mag fainter than they would be in a universe without acceleration. A
powerful
and straightforward way to assess the reliability of the SN Ia measurement
and
the conceptual framework of its interpretation is to look for cosmic
deceleration at z >= 1. This would be a clear signature of a mixed
dark-matter
and dark-energy universe. Systematic errors in the SN Ia result attributed
to
grey dust or cosmic evolution of the SN Ia peak luminosity would not show
this
change of sign. We have demonstrated proof of this concept with a single SN
Ia,
SN 1997ff at z = 1.7, found and followed by HST. The results suggest an
early
epoch of deceleration, but this is too important a conclusion to rest on
just
one object. Here we propose to use HST for observations of six SNe Ia in the
range 1.2 <= z <= 1.6, that will be discovered as a byproduct from proposed
Treasury programs for high-latitude ACS surveys. Six objects will provide a
much
firmer foundation for a conclusion that touches on important questions of
fundamental physics.
NICMOS 9360
Paschen-alpha Imaging of a SIRTF-Selected Nearby Galaxy Sample
We propose to carry out a NICMOS snapshot survey in the Paschen-alpha
{PAlpha}
emission line and H-band of the sample of galaxies being observed at 3.5 —
160
microns as part of SIRTF Nearby Galaxies Survey {SINGS} and a related
guaranteed
time survey of starburst galaxies. The PAlpha images, accessible only from
HST,
will be combined with groundbased HAlpha imaging to measure the extinction
in
the star-forming centers of these galaxies, and obtain robust, extinction-
corrected maps of the massive star formation rate {SFR}. The PAlpha data by
themselves will provide reliable `extinction- free’ SFRs, and a
cross-calibration of the {dust–affected} HAlpha– and UV–based SFRs. The
PAlpha–based SFR measurements will extend the SFR-vs.-gas density law
{Schmidt–law} to surface densities at least 30 times higher than what is
accessible using HAlpha–based SFR measurements alone, bridging the gap
between
normal galaxies and IR–luminous starbursts. Furthermore, the combination
of the
HST PAlpha images with the SIRTF images and spectra, as well as ancillary
ground–based UBVRIJHK images and GALEX UV images being obtained as part of
the
SINGS project, will provide a definitive study of the radiative transfer of
starlight and dust heating in star–forming galaxies. The processed NICMOS
images will be incorporated into the public SINGS Legacy Data Archive, to
enable
scores of follow-up studies by the astronomical community at large.
ACS 9401
The ACS Virgo Cluster Survey
We propose the most comprehensive imaging survey to date of low-redshift,
early-type galaxies. Our goal is to exploit the exceptional imaging
capabilities
of the ACS by acquiring deep images — in the SDSS g^ and z^ bandpasses
— for
163 E, S0, dE, dE, N and dS0 galaxies in Virgo, the nearest rich cluster.
This
extraordinary dataset would likely constitute one of the principal legacies
of
HST, and would have widespread applications for many diverse areas of
astrophysics. Our immediate scientific objectives are threefold: {1} measure
metallicities, ages and radii for the many thousands of globular clusters
{GCs}
in these galaxies, and use this information to derive the protogalactic mass
spectrum of each galaxy; {2} measure the central luminosity and color
profile of
each galaxy, and use this information to carry out a completely independent
test
of the merging hierarchy inferred from the GCs, with the aid of N-body codes
that simulate the merger of galaxies containing massive black holes; and {3}
calibrate the z^ -band SBF method, measure Virgo’s 3-D structure, and carry
out
the definitive study of the GC luminosity function’s precision as a standard
candle. Our proposed Virgo Cluster Survey will yield a database of
unprecedented
depth, precision and uniformity, and will enable us to study the record of
galaxy and cluster formation in a level of detail which will never be
possible
with more distant systems.
STIS/FUV 9412
The Physical Parameters of the Hottest, Most Luminous Stars as a Function of
Metallicity
We have obtained excellent, new ground-based blue optical and HAlpha spectra
of
a sample of very early-type stars in the Magellanic Clouds in order to
measure
their physical properties, for comparison with the extensive data that
exists
for higher-metallicity Galactic stars. Our aim is to understand how
effective
temperatures depend upon metallicity {necessary in determining IMFs}, and to
explore the astrophysically interesting regime of stars of extreme
temperatures,
masses, and luminosities. In order to do this, we need to measure the
stellar
wind terminal velocities for our stars, necessary to constrain the stellar
models. These can only be measured with STIS/FUV on HST. In addition, we
will
obtain higher spatial resolution data on the HAlpha line for stars for which
nebular contamination is significant in our ground-based data. We also
include
several R136 stars with excellent STIS/CCD data but which lack UV line
measures.
These new HST data will provide important information about the strengths of
stellar winds at extreme luminosities and the calibration of the Wind
Momentum-
Luminosity Relationship at lower metallicities. This proposal was highly
rated
in Cycle 9, but only 4 snapshots were obtained. We have completed the
analysis
of these plus additional data from the archives, but need spectra of the
remaining objects if we are to answer the questions we pose.
ACS 9454
The Nature of the UV Continuum in LINERs: A Variability Test
LINERs may be the most common AGNs, and the signposts of accretion onto the
massive black holes present in most galaxies. However, the LINER spectrum
is the
result of UV excitation, and, in at least some LINERs, a nuclear cluster of
hot
stars, rather than an AGN, dominates the energetics in the UV. Thus, it is
still
unknown if the UV continuum, or the optical emission lines it excites, have
anything to do with an AGN. The demographics and accretion physics of
low-luminosity AGNs hinge on this question. We propose to search for
variability
in a sample of 17 LINERs with compact UV nuclei. Variability can reveal an
AGN
component in the UV continuum, even when its light is not dominant. We will
test
systematically the handful of non-definitive reports of UV variability, and
potentially quantify the AGN contribution to the UV emission. Variability
in all
or most objects will be strong evidence that LINERs mark dormant AGNs in
most
galaxies. Alternatively, a general null detection of variability will
suggest
that, even in LINERs with additional AGN signatures, the UV continuum is
stellar
in origin. Contemporaneous monitoring with the VLA/VLBA of 11 objects which
have
radio cores {five of which we already know are radio-variable} will reveal
the
relations between UV and radio variations. The UV-variable objects will be
targeted for future, better-sampled, monitoring.
ACS 9463
Are OH/IR stars the youngest post-AGB stars? An ACS SNAPshot imaging survey
Essentially all well-characterized preplanetary nebulae {PPNs}– objects in
transition between the AGB and planetary nebula evolutionary phases – are
bipolar, whereas the mass-loss envelopes of AGB stars are strikingly
spherical.
In order to understand the processes leading to bipolar mass-ejection, we
need
to know at what stage of stellar evolution does bipolarity in the mass-loss
first manifest itself? We have recently hypothesized that most OH/IR stars
{evolved mass- losing stars with OH maser emission} are very young PPNe. We
propose an ACS/SNAPshot imaging survey of a large, morphologically unbiased
sample of these objects, selected using their IRAS 12-to-25micron colors.
Our
ground-based imaging study of OH/IR stars has revealed a few compact bipolar
objects, supporting our hypothesis. However since most objects remain
unresolved, HST observations are needed to determine how and when the
bipolar
geometry asserts itself. Our complementary program of interferometric
mapping of
the OH maser emission in our sources is yielding kinematic information with
spatial resolution comparable to that in the HST images. The HST/radio data
will
provide crucial input for theories of post-AGB stellar evolution. In
addition,
these data will also indicate whether the multiple concentric rings,
“searchlight beams”, and truncated equatorial disks recently discovered
with
HST in a few PPNs, are common or rare phenomena.
ACS 9480
Cosmic Shear With ACS Pure Parallels
Small distortions in the shapes of background galaxies by foreground mass
provide a powerful method of directly measuring the amount and distribution
of
dark matter. Several groups have recently detected this weak lensing by
large-scale structure, also called cosmic shear. The high resolution and
sensitivity of HST/ACS provide a unique opportunity to measure cosmic shear
accurately on small scales. Using 260 parallel orbits in Sloan textiti
{F775W}
we will measure for the first time: beginlistosetlength sep0cm
setlengthemsep0cm
setlength opsep0cm em the cosmic shear variance on scales <0.7 arcmin, em
the
skewness of the shear distribution, and em the magnification effect.
endlist Our
measurements will determine the amplitude of the mass power spectrum
sigma_8Omega_m^0.5, with signal-to-noise {s/n} ~ 20, and the mass density
Omega_m with s/n=4. They will be done at small angular scales where
non-linear
effects dominate the power spectrum, providing a test of the gravitational
instability paradigm for structure formation. Measurements on these scales
are
not possible from the ground, because of the systematic effects induced by
PSF
smearing from seeing. Having many independent lines of sight reduces the
uncertainty due to cosmic variance, making parallel observations ideal.
ACS/WFPC2 9481
Pure Parallel Near-UV Observations with WFPC2 within High-Latitude ACS
Survey
Fields
In anticipation of the allocation of ACS high-latitude imaging survey{s}, we
request a modification of the default pure parallel program for those WFPC2
parallels that fall within the ACS survey field. Rather than duplicate the
red
bands which will be done much better with ACS, we propose to observe in the
near-ultraviolet F300W filter. These data will enable study of the
rest-frame
ultraviolet morphology of galaxies at 0<z<1. We will determine the
morphological
k-correction, and the location of star formation within galaxies, using a
sample
that is likely to be nearly complete with multi-wavelength photometry and
spectroscopic redshifts. The results can be used to interpret observations
of
higher redshift galaxies by ACS.
ACS/NICMOS 9483
Origin and Evolution of IR Luminous Galaxies: Are z>=1 Dusty Starbursts and
z=0
ULIRGs the Same?
Interactions and mergers involving gas-rich galaxies are the main driving
mechanism behind the luminous IR galaxy phenomenon. However it is dangerous
to
extrapolate this model directly to high redshifts because massive spiral
progenitors may have been relatively uncommon at earlier epochs. Mergers and
interactions involving less massive but more gas-rich progenitors may have
occurred instead. We propose to test this hypothesis directly by imaging 12
FIR-selected, dusty starbursts at z~1 at sub-kpc resolution afforded by HST
in
the rest frame B and I {observed I and H} bands using ACS and NICMOS. While
studying higher redshift systems is clearly desirable, band-shifting and
surface
brightness dimming makes the investigations of tidal features and the nature
of
progenitors possible only out to z~ 1 {Hibbard & Vacca 1997}. From the
morphologies, surface brightnesses, and color distribution, we will
determine
the physical status of the starburst hosts, the history of tidal
interactions/mergers, and the nature of the progenitors. We will also test
for
the presence of hidden AGNs and for enhanced galaxy number density. Our 12
target galaxies form a complete sample of known ultraluminous and
hyperluminous
galaxies at 0.7<z<1.4 and represent the most distant and the best
statistical
set for investigating the nature and roles played by tidal interactions and
mergers in the dusty starburst phenomenon at high redshift.
NICMOS 9484
The NICMOS Parallel Observing Program
We propose to manage the default set of pure parallels with NICMOS. Our
experience with both our GO NICMOS parallel program and the public parallel
NICMOS programs in cycle 7 prepared us to make optimal use of the parallel
opportunities. The NICMOS G141 grism remains the most powerful survey tool
for
HAlpha emission-line galaxies at cosmologically interesting redshifts. It is
particularly well suited to addressing two key uncertainties regarding the
global history of star formation: the peak rate of star formation in the
relatively unexplored but critical 1<= z <= 2 epoch, and the amount of star
formation missing from UV continuum-based estimates due to high extinction.
Our
proposed deep G141 exposures will increase the sample of known HAlpha
emission-
line objects at z ~ 1.3 by roughly an order of magnitude. We will also
obtain a
mix of F110W and F160W images along random sight-lines to examine the space
density and morphologies of the reddest galaxies. The nature of the
extremely
red galaxies remains unclear and our program of imaging and grism
spectroscopy
provides unique information regarding both the incidence of obscured star
bursts
and the build up of stellar mass at intermediate redshifts. In addition to
carrying
out the parallel program we will populate a public database with calibrated
spectra
and images, and provide limited ground- based optical and near-IR data for
the
deepest parallel fields.
NICMOS 9485
Completing A Near-Infrared Search for Very Low Mass Companions to Stars
within
10 pc of the Sun
Most stars are fainter and less massive than the Sun. Nevertheless, our
knowledge of very low mass {VLM} red dwarfs and their brown dwarf cousins is
quite limited. Unknown are the true luminosity function {LF}, multiplicity
fraction, mass function, and mass-luminosity relation for red and brown
dwarfs,
though they dominate the Galaxy in both numbers and total mass. The best way
to
constrain these relations is a search for faint companions to nearby stars.
Such
a search has several advantages over field surveys, including greater
sensitivity to VLM objects and the availability of precise parallaxes from
which
luminosities and masses can be derived. We propose to complete our
four-filter
NICMOS snapshot search for companions to stars within 10 pc. With a 10 sigma
detection limit of M_J ~ 20 at 10 pc, we can detect companions between 10
and
100 AU that are at least 9 mag fainter than the empirical end of the main
sequence and at least 6.5 mag fainter than the brown dwarf Gl 229B. When
completed, our search will be the largest, most sensitive, volume-limited
search
for VLM companions ever undertaken. Our four-filter search will permit
unambiguous identification of VLM-companion candidates for follow-up
observation. Together with IR speckle and deep imaging surveys, our program
will
firmly establish the LF for VLM companions at separations of 1-1000 AU and
the
multiplicity fraction of all stars within 10 pc.
STIS 9507
STIS/UV snapshot survey of bright AGN
We propose a UV spectroscopic snapshot survey of bright AGN, quadrupling the
number of Seyferts UV spectra and adding dozens of new quasars, aimed at the
following goals: beginenumerate em Finding the relationship between the
intrinsic luminosity of the AGN and the maximum velocity {and width} of the
outflow emanating from it, and determining the frequency of outflows in
low-z
AGN as a function of luminosity. em Surveying IGM absorption line systems in
numerous new sight-lines. em Identifying promising targets for observations
with
the future highly sensitive Cosmic Origin Spectrograph. endenumerate A
35-minute
snapshot with exposures in either the G140L or G230L will yield spectra with
a
minimum S/N > 15 per resolution element at all wavelengths for all our
potential
targets. This will allow us to be sensitive to absorption lines to a
limiting
equivalent width of 0.3 Angstrom at the 3 Sigma level. In order to
facilitate
rapid observational followup, we waive the data proprietary period entirely.
WFPC2 9594
WFPC2 CYCLE 11 SUPPLEMENTAL DARKS pt2/3
This dark calibration program obtains 3 dark frames every day to provide
data
for monitoring and characterizing the evolution of hot pixels
FGS 9603
Monitoring FGS1r’s Interferometric Response as a Function of Spectral Color
This proposal obtains reference point source Transfer Functions {S-Curves}
for
FGS1r through the F583W filter and the F5ND attenuator at the center
position of
the FGS1r FOV for a variety of stars with different stellar spectral
colors. The
data will be added to the library of point source interferograms that was
assembled from the Cycles 8 and 9 calibration programs. These Transfer
Functions
are needed to support the analysis of GO science data for the study of
close and
wide binary star systems and for determining the angular size and shape of
extended sources. This proposal observes stars that have been observed in
previous cycles to check for long term temporal stability of the FGS1r
S-curves.
This proposal monitors the cycle 10 calibration the FGS1r Lateral Color
response
{using stars Latcol-A and Latcol-B}, as well as calibrates the "Pos/Trans"
bias
of a star’s position as determined from Transfer mode and Position mode
observations, and finally the shift of a star’s centroid when observed with
F5ND
relative to that when observed with F583W {the cross filter shift} is
calibrated
for the fainter stars in this proposal {stars brighter than V=8 can not be
observed with F583W.}
STIS 9605
CCD Dark Monitor-Part 1
Monitor the darks for the STIS CCD
STIS 9607
CCD Bias Monitor – Part 1
Monitor the bias in the 1×1, 1×2, 2×1, and 2×2 bin settings at gain=1, and
1×1
at gain = 4, to build up high-S/N superbiases and track the evolution of hot
columns.
ACS 9658
ACS Earth Flats
This program will obtain sequences of flat field images by observing the
bright
Earth. Several UV filters from the interim calibration program {9564}
require
additional exposures to obtain the required illumination. A few UV filters
from
this program will be repeated to monitor for changes in the flat fields and
to
verify the interim results. Since no streaks are observed in the UV, the
wavelength coverage is extended to longer wavelengths in order to explore
the
severity of streaks in the flats from clouds in the FOV. We have added
exposures
for the HRC in the visible filters to verify the results derived from the
L-flat
campaign and to explore the severity of streaks. We have also added
exposures on
WFC using the minimum exposure time and using filters which will not
saturate
the brightest WFC pixel by more than 10 times the full well.
ACS 9673
CCD Daily Monitor
for any source of noise in ACS CCD detectors. This programme will be
executed
once a day for the entire lifetime of ACS
WFPC2 9676
POMS Test Proposal: WFII parallel archive proposal
This is the generic target version of the WFPC2 Archival Pure Parallel
program.
The program will be used to take parallel images of random areas of the sky,
following the recommendations of the 2002 Parallels Working Group.
NICMOS 9702
NICMOS Parallel Thermal Background
NICMOS Camera 2 pure parallel exposures in the F222M and F237M filters to
establish the stability of the HST+NCS+Instrument thermal emission. This
data
will be compared against the already available Camera 3 measurements in
F222M
which show an increased thermal background.
STIS 9706
STIS Pure Parallel Imaging Program: Cycle 10
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are preliminary reports of
potential non-nominal performance that will be investigated.)
HSTAR 8947: GSACQ(2,3,2) FL Backup, scan step limit exceeded on FGS 2.
GSACQ(2,3,2) at 11:52:41 resulted in fine lock
back-up on FGS 3 with scan
step limit exceeded on FGS 2.Observations affected:
STIS 55 to 57, ACS 111,
NICMOS 50 . Under investigation. The guide star
acquisition for this observation
was non-nominal, further analysis will determine if
a repeat observation is required.
COMPLETED OPS REQs: NONE
OPS NOTES EXECUTED: NONE
SCHEDULED SUCCESSFUL FAILURE TIMES
FGS GSacq 08 08
FGS REacq 07 07
FHST Update 16 16
LOSS of LOCK
SIGNIFICANT EVENTS: None
