This Echo is READ ONLY !   NO Un-Authorized Messages Please!
 ~~~~~~~~~~~~~~~~~~~~~~~~   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

14 Apr 2003

HUBBLE SPACE TELESCOPE

DAILY REPORT #3340

PERIOD COVERED: DOYS 101-103

Part 3 of 6

NICMOS 9423

NICMOS Observations of Transient Infrared Jets in the Galactic
Microquasar GRS1915+105

We propose to use HST/NICMOS to make Target of Opportunity
observations of the galactic microquasar GRS1915+105. This source
possesses transient radio jets which exhibit apparent superluminal
motions, and resolved infrared emission from these jets has been
observed in GRS1915+105 {Sams, Eckart, and Sunyaev, 1996; Eikenberry
and Fazio, 1996}. Because the jet ejection events are correlated with
X-ray outbursts, we will use observations of X-ray flares with the
Rossi X-Ray Timing Explorer to trigger the HST observations. We will
then monitor GRS1915+105 periodically with NICMOS, obtaining relative
astrometry, photometry, polarimetry, and grism spectroscopy of the
jets and the parent object. These observations will allow us to
greatly increase our understanding of the jets' radiative mechanisms
and physical conditions, and their evolution with time. We require
the capabilities of HST and NICMOS due to the small angular
separations between the jets and the parent object {increasing from
~ 0.1 to ~ 0.8 arcsec over the span of the TOO observations} and the
high reddening towards GRS1915+105 {A_V ~ 30 mag}. 

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. 

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. 

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. 

SNAP/STIS 9434

A SNAPSHOT Survey of the Hot Interstellar Medium

We propose to obtain SNAPSHOT STIS echelle observations of key
tracers of hot interstellar gas {CIV, NV and SiIV} for selected FUSE
Team OVI survey targets with known UV fluxes. By taking advantage of
the SNAPSHOT observing mode we will efficiently obtain a large number
of spectra suitable for the study of the highly ionized hot component
of the interstellar medium {ISM}. Our goals are to explore the
physical conditions in and distribution of such gas, as well as to
explore the nature of the interfaces between the hot ISM and the
other interstellar gas phases. Using inter--comparisons of the
various ionic ratios for CIV, NV, OVI and SiIV, we will be able to
discriminate between the various models for the production of the
highly ionized gas in the Galactic ISM. The survey will also enable
detailed studies of regions already known to contain hot gas through
X-ray emission measurements {e.g., SNRs and radio loops}. The
proposed SNAPSHOT observations will extend our previous Cycle 9
survey {which was compromised by the STIS side 1 failure}, and should
roughly double the number of stars for which high quality STIS
observations of the important hot gas tracers are available, enabling
us to derive a truly global view of the hot ISM. 

STIS 9608

CCD Bias Monitor - Part 2

Monitor the bias in the 1x1, 1x2, 2x1, and 2x2 bin settings at
gain=1, and 1x1 at gain = 4, to build up high-S/N superbiases and
track the evolution of hot columns.

STIS 9606

CCD Dark Monitor-Part 2

Monitor the darks for the STIS CCD.

 - Continued -

@Message posted automagically by IMTHINGS POST 1.30
---