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       # 4492

PERIOD COVERED: UT November 19, 2007 (DOY 323)

OBSERVATIONS SCHEDULED

WFPC2 10583

Resolving the LMC Microlensing Puzzle: Where Are the Lensing Objects ?

We are requesting 32 HST orbits to help ascertain the nature of the

population that gives rise to the observed set of microlensing events

towards the LMC. The SuperMACHO project is an ongoing ground-based

survey on the CTIO 4m that has demonstrated the ability to detect LMC

microlensing events in real-time via frame subtraction. The improvement

in angular resolution and photometric accuracy available from HST will

allow us to 1} confirm that the detected flux excursions arise from LMC

source stars rather than extended objects {such as for background

supernovae or AGN}, and 2} obtain reliable baseline flux measurements

for the objects in their unlensed state. The latter measurement is

important to resolve degeneracies between the event timescale and

baseline flux, which will yield a tighter constraint on the microlensing

optical depth.

WFPC2 11024

WFPC2 CYCLE 15 INTERNAL MONITOR

This calibration proposal is the Cycle 15 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 {both gain 7 and

gain 15 -- to test stability of gains and bias levels}, a test for

quantum efficiency in the CCDs, and a monitor for possible buildup of

contaminants on the CCD windows. These also provide raw data for

generating annual super-bias reference files for the calibration

pipeline.

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.

S/C 4974

TRTTEST

The Transient Response Test is for the periodic performance monitoring

of the FGS 2R servo A mechanism.

WFPC2 11035

Photometric Zero Points Closeout

Updated zero points will be obtained by observing NGC 2419 for which

extensive BVRI ground based observations exist, and the field in 47 Tuc

used for frequent monitoring of ACS. For NGC 2419 emphasis is given to

repeating observations obtained in earlier epochs, and to covering

filters near standard BVRI. For 47 Tuc emphasis is given to covering a

large set of broadband filters from F300W through F850LP to maximize

transformation capabilities between filters of WFPC2 and ACS.

WFPC2 11070

WFPC2 CYCLE 15 Standard Darks - part II

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 11126

Resolving the Smallest Galaxies

An order of magnitude more dwarf galaxies are expected to inhabit the

Local Group, based on currently accepted galaxy formation models, than

have been observed. This discrepancy has been noted in environments

ranging from the field to rich clusters, with evidence emerging that

lower density regions contain fewer dwarfs per giant than higher density

regions, in further contrast to model predictions. One possible

explanation for this involves the effects of reionization on the forming

galaxies and naturally explains both the dearth of dwarf galaxies and

the apparent environmental dependence. However, before such theories can

be fully tested, we require a better understanding of the distribution

of dwarf galaxies. Currently, there is no complete census of the

faintest dwarf galaxies in any environment. The discovery of the

smallest and faintest dwarfs is hampered by the limitations in detecting

such faint and low surface brightness galaxies, and this is compounded

by the great difficulty in determining accurate distances to, or

ascertaining group membership for, such faint objects. The M81 group

provides a unique means for establishing membership for galaxies in a

low density region complete to magnitudes as faint as M_R ~ -7. With a

distance modulus of 27.8, the tip of the red giant branch {TRGB} appears

at I ~ 24, just within the reach of ground based surveys. We currently

have surveyed a 30 square degree region around M81 with the

CFHT/Megacam. From these images we have detected 15 new candidate dwarf

galaxies. We propose to use the HST with WFPC2 to image these 15

galaxies in F606W and F814W bands in order to construct a

color-magnitude diagram down to I = 25.5 from which to measure accurate

TRGB distances to these candidate galaxies and determine star formation

and metallicity histories. The overall project will provide a survey of

the dwarf galaxies in the M81 group environment with unprecedented

completeness to a limit of M_R < -7.

WFPC2 11130

AGNs with Intermediate-mass Black Holes: Testing the Black Hole-Bulge

Paradigm, Part II

The recent progress in the study of central black holes in galactic

nuclei has led to a general consensus that supermassive {10^6-10^9 solar

mass} black holes are closely connected with the formation and

evolutionary history of large galaxies, especially their bulge

component. Two outstanding issues, however, remain unresolved. Can

central black holes form in the absence of a bulge? And does the mass

function of central black holes extend below 10^6 solar masses?

Intermediate-mass black holes {<10^6 solar masses}, if they exist, may

offer important clues to the nature of the seeds of supermassive black

holes. Using the SDSS, our group has successfully uncovered a new

population of AGNs with intermediate-mass black holes that reside in

low-luminosity galaxies. However, very little is known about the

detailed morphologies or structural parameters of the host galaxies

themselves, including the crucial question of whether they have bulges

or not. Surprisingly, the majority of the targets of our Cycle 14 pilot

program have structural properties similar to dwarf elliptical galaxies.

The statistics from this initial study, however, are really too sparse

to reach definitive conclusions on this important new class of black

holes. We wish to extend this study to a larger sample, by using the

Snapshot mode to obtain WFPC2 F814W images from a parent sample of 175

AGNs with intermediate-mass black holes selected from our final SDSS

search. We are particularly keen to determine whether the hosts contain

bulges, and if so, how the fundamental plane properties of the host

depend on the mass of their central black holes. We will also

investigate the environment of this unique class of AGNs.

WFPC2 11218

Snapshot Survey for Planetary Nebulae in Globular Clusters of the Local

Group

Planetary nebulae {PNe} in globular clusters {GCs} raise a number of

interesting issues related to stellar and galactic evolution. The number

of PNe known in Milky Way GCs, 4, is surprisingly low if one assumes

that all stars pass through a PN stage. However, it is likely that the

remnants of stars now evolving in Galactic GCs leave the AGB so slowly

that any ejected nebula dissipates long before the star becomes hot

enough to ionize it. Thus there should not be ANY PNe in Milky Way

GCs--but there are four! It has been suggested that these PNe are the

result of mergers of binary stars within GCs, i.e., that they are

descendants of blue stragglers. The frequency of occurrence of PNe in

external galaxies poses more questions, because it shows a range of

almost an order of magnitude. I propose a Snapshot survey aimed at

discovering PNe in the GC systems of Local Group galaxies more distant

than the Magellanic Clouds. These clusters, some of which may be much

younger than their counterparts in the Milky Way, might contain many

more PNe than those of our own galaxy. I will use the standard technique

of emission-line and continuum imaging, which easily discloses PNe.

FLIGHT OPERATIONS SUMMARY:

Significant Spacecraft Anomalies: (The following are preliminary reports

of potential non-nominal performance that will be investigated.)

HSTARS:

11072 - GSAcq(1,2,2) failed to RGA Hold (Gyro Control)

   Upon acquisition of signal (AOS) at 324/02:23:17, the

   GSAcq(1,2,2)scheduled at 324/02:17:29 - 02:25:34 had failed to RGA Hold

   due to (QF2STOPF) stop flag indication on FGS-2. Pre-acquisition OBAD1

   attitude correction value not available due to LOS. Pre-acq OBAD2 had

   (RSS) value of 12.62 arcseconds. Post-acq OBAD/MAP not scheduled.

11073 - REAcq (1,2,2) results in FLBU (1,0,1)

   REAcq (1,2,2) scheduled from 324/06:48:11 - 06:55:43 failed to fine lock

   back up (FLBU 1,0,1) due to QSTOP flag on FGS2. Pre-acquisition OBAD #1

   had an RSS value of 2618.65 arc-seconds and OBAD #2 had an RSS value of

   9.11 arc-seconds. An OBAD MAP was not scheduled. No 486 STB messages

   were noted. This reacquisition is using the same guide stars as were

   used in HSTAR 11072.

COMPLETED OPS REQUEST: (None)

COMPLETED OPS NOTES: (None)

                       SCHEDULED      SUCCESSFUL 

FGS GSacq               05                  04 

FGS REacq               07                  07 

OBAD with Maneuver 28                  28                                  

SIGNIFICANT EVENTS:

Flash Report: TRTT Successful

The sixteenth run of the Transient Response Trending Test (TRTT) was

successfully completed via Ops Request 18156 at 323/15:57z this morning.

Analysis will be presented at the next GSAWG meeting.