Hubble Space Telescope Daily Report # 3182 20 Aug 2002

HUBBLE SPACE TELESCOPE

DAILY REPORT        # 3182
PERIOD COVERED: DOY 231
OBSERVATIONS SCHEDULED (see HSTARS below for possible observation problems)
NICMOS 8790
NICMOS Post-SAA calibration – CR Persistence Part 1.
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.
STIS/CCD 8902
Dark Monitor-Part 2.
The Space Telescope Imaging Spectrograph (CCD) was used to monitor the darks.
STIS/CCD 8904
Bias Monitor-Part 2.
The Space Telescope Imaging Spectrograph (CCD) was used to 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 in order

to build up high-S/N superbiases and track the evolution of hot columns.
STIS/MA1/MA2 8920
Cycle 10 MAMA Dark Measurements.
the MAMA detector dark noise, and is the primary means of checking on health of

the MAMA detectors systems through frequent monitoring of the background count

rate.
WF/PC-2 8935
Cycle 10 Standard Darks.
The WF/PC-2 was used to obtain 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 8938
WFPC2 CYCLE 9 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.
WF/PC-2 8939
Cycle 10 Internal Monitor.
The WF/PC-2 was used to calibrate the internal monitor, to be run weekly to

monitor the health of the cameras.
STIS 9035
Spatially Resolved Spectroscopy of Uranus and Neptune
We propose to use STIS to obtain data cubes for Uranus {Cycle 10} and Neptune

{Cycle 11}. The spectrum between 290 and 1020 nm is sampled at 2000

wavelengths.

The north-south position on the planetary disk is sampled along the slit every

0.05″. The east-west position is sampled by successive exposures every 0.05″

{longward of 520 nm wavelength} and 0.15″ {shortward of 520 nm}. Such data have

never been obtained. Only HST, with STIS, has the capability to record spatial

variations of narrow methane and hydrogen absorption and Raman scattering

features. We have obtained such data for Saturn by ground-based observations

which permitted a comprehensive understanding of the vertical haze and cloud

structure as a function of latitude. Similar improvements are expected from the

proposed data for Uranus and Neptune. HST has revealed exciting images of

Uranus

and Neptune while their quantitative analysis has been slow due to limitations

in available filters. Our short, spatially-resolved spectroscopic program will

reveal accurate spectral shapes across each WFPC2 filter which then will

greatly

improve the reliability of interpretations based on hundreds of past and future

WFPC2 images. Similarly, WFPC2 images of Titan required the addition of STIS

spectra before the latest improvements in our understanding of its atmosphere

were possible.
GO 9172
Molecular Hydrogen in the Damped LyAlpha Absorber of Q1331+170
We wish to search for the Lyman and Werner absorption lines of molecular

hydrogen {rest LambdaLambda = 1104 to 911 Angstrom} associated with the

well-studied damped LyAlpha and 21-cm absorber at z=1.776 in Q1331+170. The

rare

detection of C I absorption in this system make this a promising candidate

for a

search. After detecting H_2, we plan to measure the relative population in the

individual rotation states. The J = 0, 1, 2, 3 states will yield the kinetic

temperature of the gas, while the weak J = 4 and higher states will measure {or

limit} the local UV radiation field and hydrogen density. The detection of

C I^*

has been used to measure the cosmic microwave background temperature at

z=1.776,

and test the validity of the Big Bang model. The observed population of the

fine

structure levels of C I can be explained entirely by the expected CMB

radiation,

with surprisingly strong limits on local sources of excitation. The H_2

spectrum

will enable us to check this result, by allowing us to make an independent

estimate of the rate of UV and collisional pumping of the C I^* levels.
STIS/CCD 9317
Pure Parallel Imaging Program: Cycle 10.
program for STIS during cycle 10.
NICMOS 9321
Dark current, shading profile, and read noise monitoring program
for all three NICMOS cameras from the onset of normal NCS operations throughout

the start of Cycle 11.
NICMOS 9322
NICMOS ACCUM Darks
The goal is to obtain ACCUM darks with exposure time=256 seconds with

NREADS=25,

taken away from the SAA. These are needed to calibrate the post-SAA darks that

will be used to remove CR persistence from NICMOS science images. In the early

Cycle 11 calibration plan they should be obtained every 4 weeks. We will

evaluate need for repeats later
NICMOS 9326
NICMOS Cycle 10 Early Calibration Monitor
This calibration program is the early Cycle 10 NICMOS monthly monitor

program. A

series of flat field observations will be obtain to monitor the stability and

health of the NICMOS detectors.
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