HST Daily Report # 3331
HUBBLE SPACE TELESCOPE
DAILY REPORT # 3331
PERIOD COVERED: DOY 90
OBSERVATIONS SCHEDULED
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/WFC 9351
Determining Hubble’s Constant from Observations of Cepheids in the Host
Galaxy
of SN Ia 1994ae
We propose to determine the luminosity of the type Ia supernova {SN Ia}
1994ae
by observing Cepheids in the host spiral galaxy NGC 3370. Modern CCD
photometry
has yielded an extremely tight Hubble diagram for SNe Ia with a precisely
determined intercept {i.e., Delta H_0/H_0} 1 measurement of the true
Hubble
constant is still limited by the calibration. The HST calibration of all
but a
few SNe Ia observed to date is significantly compromised by the
systematics of
photographic photometry and host galaxy extinction, as well as by the
photometric uncertainties associated with WFPC2. In contrast, SN 1994ae
is one
of the very best-observed SNe Ia with CCD photometry. The exquisite B, V,
R, and
I light curves are well-sampled beginning 10 days before maximum
brightness, and
they indicate little reddening. From our supernova photometry and the
current
provisional SN Ia calibration we would find a distance of 30 +/- 2.1 Mpc,
well
within the range where ACS can accurately observe Cepheid light curves
and
distinguish Cepheids from nonvariable stars.
STIS/CCD/MA1 9357
Towards a global understanding of accretion physics –, Clues from an UV
spectroscopic survey of cataclysmic variables
Accretion inflows and outflows are fundamental phenomena in a wide
variety of
astrophysical environments, such as Young Stellar Objects, galactic
binaries,
and AGN. Observationally, cataclysmic variables {CVs} are particularly
well
suited for the study of accretion processes. We propose to carry out a
STIS UV
spectroscopic snapshot survey of CVs that fully exploits the diagnostic
potential of these objects for our understanding of accretion physics.
This
survey will provide an homogenous database of accretion disc and wind
outflow
spectra covering a wide range of mass transfer rates and binary
inclinations. We
will analyse these spectra with state-of-the-art accretion disc model
spectra
{SYNDISK}, testing our current knowledge of the accretion disc structure,
and,
thereby, providing new insight into the so far not well understood
process of
viscous dissipation. We will use our parameterised wind model PYTHON for
the
analysis of the radiation driven accretion disc wind spectra, assessing
the
fundamental question whether the mass loss rate correlates with the disc
luminosity. In addition, our survey data will identify a number of
systems in
which the white dwarf significantly contributes to the UV flux,
permitting an
analysis of the impact of mass accretion on the evolution of these
compact
stars. This survey will at least double, if not triple, the number of
high-quality accretion disc / wind outflow / accreting white dwarf
spectra, and
we waive our proprietary rights to permit a timely use of this database.
HST 9382
A Large Targeted Survey for z < 1.6 Damped Lyman Alpha Lines in SDSS QSO
MgII-FeII Systems.
We have searched the first public release of SDSS QSO spectra for low-z
{z<1.65}
metal absorption lines and found over 200 large rest equivalent width
MgII-FeII
systems. Previously, we empirically showed that such systems are good
tracers of
large neutral gas columns, with ~50% being classical damped Lyman alpha
{DLA}
systems {N_HI>=2*10^20 cm^-2}. Here we propose to follow up a
well-defined
subset of 79 of them to search for DLAs with 0.47<z<1.60. Only QSOs
brighter
than g’=19 were selected. The QSO emission and DLA absorption redshifts
were
constrained to virtually eliminate data loss due to intervening Lyman
limit
absorption. Consequently, we expect to discover ~40 new DLAs, which is a
three-fold increase in this redshift interval. This will significantly
improve
our earlier low-z DLA statistical results on their incidence,
cosmological mass
density, and N_HI distribution. The results will also allow us to better
quantify the empirical DLA — metal-line correlation. With this improved
understanding, the need for follow-up UV spectroscopy will lessen and,
with the
release of the final database of SDSS QSO spectra {an ~25-fold increase},
the
number of low-z DLAs could be increased arbitrarily. Thus, the power of
the
large and statistically-sound SDSS database in combination with a proven
technique for finding low-z DLAs will, over the next few years,
essentially
solve the problem of making an accurate determination of the cosmic
evolution of
the neutral gas component down to z~0.4.
STIS/CCD 9432
The Radio-Loud BAL QSO PKS 1004+13: A Key to Understanding QSO Outflows?
Accretion and outflows drive astrophysical engines on many scales. In
powerful
QSOs, broad absorption lines {BALs} reveal partially-ionized outflows to
~0.1c.
What is the geometry of the flow, its origin, the driving mechanism? Why
are the
most extreme outflows always seen in radio-weak QSOs? Such basic
questions
remain unanswered. Plausibly, radiation pressure can drive an equatorial
wind
off the dusty torus or outer accretion disk. Are BAL QSOs seen nearly
edge-on,
as this scenario requires? We don’t know because there is no good
inclination
indicator for these generally radio-weak QSOs. The bright, low-redshift
QSO PKS
1004+13 may be a valuable exception. Its dominant radio lobes imply a
near
edge-on view, while low SNR IUE spectra suggest it is a BAL QSO. Indirect
indications that it’s a BAL QSO are: very weak soft X-ray flux, high
scattering
polarization, and unusually weak ionO3. It also shows clear
high-ionization
non-BAL absorption with partial continuum coverage. We propose high
quality UV
spectroscopy to confirm its BAL QSO identity. PKS 1004+13 would be only
the
second known BAL QSO with powerful radio jets, hence known inclination,
providing a clear test of the outflow geometry, and the only such object
at low
redshift, allowing high SNR, high spatial resolution followup.
STIS 9441
Zinc Abundances in Damped Ly-Alpha Systems at z < 0.5: A Missing Link in
the
Chemical History of Galaxies
The evolution of metallicity in damped Lyman alpha {DLA} quasar
absorption
systems is an important constraint on the global star formation history
of the
universe, but remains a big puzzle at present. The H I column density
weighted
mean metallicity in DLAs is expected to rise to solar values at low
redshifts,
based on cosmic chemical evolution models, because the mass-weighted mean
metallicity of local galaxies is near- solar. However, current DLA
abundance
studies are highly uncertain and cannot distinguish between evolution and
no
evolution in the mean metallicity at redshifts 0.4 < z < 3.5. The
existing data
are particularly incomplete because no Zn measurements exist for z < 0.4,
and
only 2 exist for z < 0.5, which spans the past 35-45 % of the age of the
universe. To pin down the cosmic age-metallicity relation all the way to
the
present epoch, we propose to measure Zn abundances in five DLAs at 0.1 <
z <
0.5. We propose to use HST STIS because it is the only existing
instrument that
can measure the necessary UV lines. Our observations will clearly
distinguish
between no metallicity evolution vs. the predicted evolution. Our data
will
also
provide Cr measurements, which will help to estimate the dust abundance.
The
proposed observations are crucial for tying together the absorption and
emission
histories of gas and stars in galaxies and for clarifying the relation of
DLAs
to present-day galaxies.
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 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 9482
ACS Pure Parallel Lyman-Alpha Emission Survey {APPLES}
Ly-alpha line emission is an efficient tool for identifying young
galaxies at
high redshift, because it is strong in galaxies with young stars and
little or
no dust — properties expected in galaxies undergoing their first burst
of
star- formation. Slitless spectroscopy with the ACS Wide-Field Camera and
G800L
grism allows an unmatched search efficiency for such objects over the
uninterrupted range 4 <~ z <~ 7. We propose the ACS Pure Parallel
Ly-alpha
Emission Survey {“APPLES”}, to exploit this unique HST capability and
so
obtain the largest and most uniform sample of high redshift Ly-alpha
emitters
yet. Parallel observations will allow this survey to be conducted with
minimal
impact on HST resources, and we will place reduced images and extracted
spectra
in the public domain within three months of observation. We aim to find ~
1000
Ly-alpha emitters, 5 times the biggest current sample of Ly-alpha
emitters.
This
unprecedented sample will provide robust statistics on the populations
and
evolution of Ly-alpha emitters between redshifts 4–7; a robust
measurement of
the reionization redshift completely independent of the Gunn-Peterson
trough;
spatial clustering information for Ly-alpha emitters which would let us
probe
their bias function and hence halo mass as a function of redshift; many
galaxies
at redshift exceeding 6; and lower redshift serendipitous discoveries.
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.
WFPC2 9592
WFPC2 CYCLE 11 Standard Darks
This dark calibration program obtains dark frames every week in order to
provide
data for the ongoing calibration of the CCD dark current rate, and to
monitor
and characterize the evolution of hot pixels. Over an extended period
these
data
will also provide a monitor of radiation damage to the CCDs.
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
WFPC2 9595
WFPC2 CYCLE 11 SUPPLEMENTAL DARKS pt3/3
This dark calibration program obtains 3 dark frames every day to provide
data
for monitoring and characterizing the evolution of hot pixels.
WFPC2 9596
WFPC2 CYCLE 11 INTERNAL MONITOR
This calibration proposal is the Cycle 11 routine internal monitor for
WFPC2, to
be run weekly to monitor the health of the cameras. A variety of internal
exposures are obtained in order to provide a monitor of the integrity of
the CCD
camera electronics in both bays {gain 7 and gain 15}, a test for quantum
efficiency in the CCDs, and a monitor for possible buildup of
contaminants on
the CCD windows.
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 9606
CCD Dark Monitor-Part 2
Monitor the darks for the STIS CCD.
STIS 9608
CCD Bias Monitor – Part 2
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.
STIS 9615
Cycle 11 MAMA Dark Monitor
This test performs the routine monitoring of the MAMA detector dark
noise. This
proposal will provide the primary means of checking on health of the MAMA
detectors systems through frequent monitoring of the background count
rate. The
purpose is to look for evidence of change in dark indicative of detector
problem
developing.
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.
WFPC2/PC1 9663
Focus Monitoring
The HST focus is monitored using WFPC2/PC1. In principle ACS/HRC should
provide
superior capability for monitoring the HST focus. Since most of the HST
science
will shift to ACS in Cycle 11 trending observations are continued with
this
program to establish the focus of WFPC2/PC1 {and hence HST} and ACS/HRC
{and WFC
to a lessor degree} using exposures over full orbits that are taken in
parallel.
With parallel exposures breathing cancels out for the relative camera
offset.
ACS 9673
CCD Daily Monitor
This program consists of basic tests to monitor, the read noise, the
development
of hot pixels and test 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
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
This is the default archival pure parallel program for STIS during cycle
10.
WFPC2 9710
POMS Test Proposal: WFII backup parallel archive proposal
This is a POMS test proposal designed to simulate scientific plans.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are preliminary reports
of
potential non-nominal performance that will be investigated.) None
COMPLETED OPS REQs: None
OPS NOTES EXECUTED: None
SCHEDULED SUCCESSFUL FAILURE TIMES
FGS GSacq 10 10
FGS REacq 06 06
FHST Update 23 23
LOSS of LOCK
SIGNIFICANT EVENTS: None