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22 April 2003

HUBBLE SPACE TELESCOPE

DAILY REPORT #3346

PERIOD COVERED:  DOY 111

Part 1 of 3

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 9293

Massive Black Holes in Early Type Galaxies

3x10^6 Msun < M_BH < 3x10^9 Msun} at the centers of galaxies and the
velocity dispersions of their bulges. However, uncertainties over the
exact slope of the correlation still remain, and it is not known if
such a relation extends to black holes of lower and higher masses.
The discovery of small {r ~ a few hundred pc}, well defined, dust and
gas disks in the nuclei of some active elliptical galaxies opened a
new avenue for measuring central mass distributions. When ionized gas
is present, a small number of high spatial resolution {e.g. STIS}
spectra are sufficient to characterize the disk dynamics and the
galaxy's central mass {e.g., M87, M81, NGC 4374}. We propose to use
STIS spectroscopy to measure black hole masses, using gas dynamics,
in the centers of several brightest cluster galaxies {BCGs}, 2 nearby
galaxies with low velocity dispersions, and a number of elliptical
galaxies known to harbor small nuclear dust disks. The proposed
targets encompass a wide range of black hole masses, allowing us to
fully examine the M_BH -- sigma relationship. We will also obtain
H-alpha and continuum images to fully characterize the gaseous and
dust morphology as well as stellar surface profile in the central
regions.

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.

NICMOS/STIS CCD 9405

The Origin of Gamma-Ray Bursts

The rapid and accurate localization of gamma-ray bursts {GRBs}
promised by a working HETE-2 during the coming year may well
revolutionize our ability to study these enigmatic, highly luminous
transients. We propose a program of HST and Chandra observations to
capitalize on this extraordinary opportunity. We will perform some of
the most stringent tests yet of the standard model, in which GRBs
represent collimated relativistic outflows from collapsing massive
stars. NICMOS imaging and STIS CCD spectroscopy will detect broad
atomic features of supernovae underlying GRB optical transients, at
luminosities more than three times fainter than SN 1998bw. UV,
optical, and X-ray spectroscopy will be used to study the local ISM
around the GRB. Chandra spectroscopy will investigate whether the GRB
X-ray lines are from metals freshly ripped from the stellar core by
the GRB. HST and CTIO infra-red imaging of the GRBs and their hosts
will be used to determine whether `dark' bursts are the product of
unusually strong local extinction; imaging studies may for the first
time locate the hosts of `short' GRBs. Our early polarimetry and
late-time broadband imaging will further test physical models of the
relativistic blast wave that produces the bright GRB afterglow, and
will provide unique insight into the influence of the GRB environment
on the afterglow. 

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 * Origin: SpaceBase(tm) Pt 1 -14.4- Van BC Canada 604-473-9358 (1:153/719.1)

SEEN-BY: 633/267 270

@PATH: 153/719 715 7715 140/1 106/2000 633/267