Daily Report #4479

Notice: Due to the conversion of some ACS WFC or HRC observations into
WFPC2, or NICMOS observations after the loss of ACS CCD science
capability in January, there may be an occasional discrepancy between
a proposal's listed (and correct) instrument usage and the abstract
that follows it.


HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT****** # 4479

PERIOD COVERED: UT October 30, 2007 (DOY 303)

OBSERVATIONS SCHEDULED

NIC1/NIC2/NIC3 11330

NICMOS Cycle 16 Extended Dark

This takes a series of Darks in parallel to other instruments.

NIC1/NIC2/NIC3 8794

NICMOS Post-SAA calibration - CR Persistence Part 5

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 DARKs. 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.

NIC2 11197

Sweeping Away the Dust: Reliable Dark Energy with an Infrared Hubble
Diagram

We propose building a high-z Hubble Diagram using type Ia supernovae
observed in the infrared rest-frame J-band. The infrared has a number
of exceptional properties. The effect of dust extinction is minimal,
reducing a major systematic that may be biasing dark energy
measurements. Also, recent work indicates that type Ia supernovae are
true standard candles in the infrared meaning that our Hubble diagram
will be resistant to possible evolution in the Phillip's relation over
cosmic time. High signal-to-noise measurements of 16 type Ia events at
z~0.4 will be compared with an independent optical Hubble diagram from
the ESSENCE project to test for a shift in the derived dark energy
equation of state due to a systematic bias. In Cycle 15 we obtained
NICMOS photometry of 8 ESSENCE supernovae and are awaiting template
observations to place them on the IR Hubble diagram. Here we request
another 8 supernovae be studied in the final season of the ESSENCE
search. Because of the bright sky background, H-band photometry of
z~0.4 supernovae is not feasible from the ground. Only the superb
image quality and dark infrared sky seen by HST makes this test
possible. This experiment may also lead to a better, more reliable way
of mapping the expansion history of the universe with the Joint Dark
Energy Mission.

NIC2 11219

Active Galactic Nuclei in nearby galaxies: a new view of the origin of
the radio-loud radio- quiet dichotomy?

Using archival HST and Chandra observations of 34 nearby early-type
galaxies {drawn from a complete radio selected sample} we have found
evidence that the radio-loud/radio-quiet dichotomy is directly
connected to the structure of the inner regions of their host galaxies
in the following sense: [1] Radio-loud AGN are associated with
galaxies with shallow cores in their light profiles [2] Radio-quiet
AGN are only hosted by galaxies with steep cusps. Since the brightness
profile is determined by the galaxy's evolution, through its merger
history, our results suggest that the same process sets the AGN
flavour. This provides us with a novel tool to explore the
co-evolution of galaxies and supermassive black holes, and it opens a
new path to understand the origin of the radio-loud/radio-quiet AGN
dichotomy. Currently our analysis is statistically incomplete as the
brightness profile is not available for 82 of the 116 targets. Most
galaxies were not observed with HST, while in some cases the study is
obstructed by the presence of dust features. We here propose to
perform an infrared NICMOS snapshot survey of these 82 galaxies. This
will enable us to i} test the reality of the dichotomic behaviour in a
substantially larger sample; ii} extend the comparison between
radio-loud and radio-quiet AGN to a larger range of luminosities.

WFPC2 11167

A Unique High Resolution Window to Two Strongly Lensed Lyman Break
Galaxies

On rare occasions, the otherwise very faint Lyman Break Galaxies
{LBGs} are magnified by gravitational lensing to provide exceptional
targets for detailed spectroscopic and imaging studies. We propose HST
WFPC2 and NICMOS imaging of two strongly lensed Lyman Break Galaxies
{LBGs} that were recently discovered by members of our team. These two
LBGs -- the "8 O'Clock Arc" and the "SDSS J1206+5142 Arc" -- are
currently the brightest known LBGs, roughly 3 times brighter than the
former record-holder, MS1512-cB58 {a.k.a. "cB58"}. The z=2.73 "8
O'Clock Arc" extends ~10 arcsec in length and is magnified by a factor
of 12. The z=2.00 "SDSS J1206+5142 Arc" also extends ~10 arcsec in
length and is magnified by a factor of 30. Due to their brightness and
magnification, these two strongly lensed LBGs offer an unprecedented
opportunity for the very detailed investigation of two individual
galaxies at high redshift. We are currently pursuing a vigorous
ground-based campaign to obtain multi-wavelength {UV, optical, NIR,
radio} observations of these two LBGs, but our campaign currently
lacks a means of obtaining high-resolution optical/NIR imaging -- a
lack that currently only HST can address. Our prime objective for this
proposal is to obtain high resolution HST images of these two systems
with two-orbit WFPC2 images in the BVI bands and two-orbit NICMOS/NIC2
images in the J and H bands. These data will allow us to construct
detailed lensing models, probe the mass and light profiles of the
lenses and their environments, and constrain the star formation
histories and rest-frame UV/optical spectral energy distributions of
the LBGs.

WFPC2 11179

Dynamics of Clumpy Supersonic Flows in Stellar Jets and in the
Laboratory

We propose to reobserve three stellar jets in order to quantify how
rapidly clumps in these flows accelerate and decelerate, and to
compare the results with ongoing numerical simulations and laboratory
experiments. Each jet has been imaged twice before with HST, and
precise proper motions have been measured for all emitting knots in
the jets. Images from the first two epochs show clear differential
motions between adjacent clumps, as well as shear, and possibly
fragmentation. The proposed third epoch will enable us to measure the
first ever accelerations in jets, quantify errors in existing proper
motion measurements, and observe in real time how fluid instabilities
develop in supersonic flows. The new images will make it possible to
compare the behavior of astrophysical flows directly with numerical
simulations and with laboratory experiments of bow shocks and clumpy
flows in progress at the Omega laser facility.

FLIGHT OPERATIONS SUMMARY:

Significant Spacecraft Anomalies: (The following are preliminary
reports of potential non-nominal performance that will be
investigated.)

HSTARS: (None)

COMPLETED OPS REQUEST: (None)

COMPLETED OPS NOTES: (None)

************************ SCHEDULED***** SUCCESSFUL

FGS GSacq************** 05****************** 05
FGS REacq************** 08****************** 08
OBAD with Maneuver **** 26****************** 26

SIGNIFICANT EVENTS: (None)