HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

 

DAILY REPORT    #4644

 

PERIOD COVERED: 5am July 1 - 5am July 2, 2008 (DOY 183/0900z-184/0900z)

 

OBSERVATIONS SCHEDULED

 

ACS/SBC 11158

 

HST Imaging of UV Emission in Quiescent Early-type Galaxies

 

We have constructed a sample of early type galaxies at z~0.1 that have

blue UV-optical colors, yet also show no signs of optical emission, or

extended blue light. We have cross-correlated the SDSS catalog and the

Galaxy Evolution Explorer Medium Imaging Survey to select a sample of

galaxies where this UV emission is strongest. The origin of the UV

rising flux in these galaxies continues to be debated, and the

possibility that some fraction of these galaxies may be experiencing low

levels of star formation cannot be excluded. There is also a possibility

that low level AGN activity {as evidenced by a point source} is

responsible We propose to image the UV emission using the HST/SBC and to

explore the morphology of the UV emission relative to the optical light.

 

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.

 

FGS 11212

 

Filling the Period Gap for Massive Binaries

 

The current census of binaries among the massive O-type stars is

seriously incomplete for systems in the period range from years to

millennia because the radial velocity variations are too small and the

angular separations too close for easy detection. Here we propose to

discover binaries in this observational gap through a Faint Guidance

Sensor SNAP survey of relatively bright targets listed in the Galactic O

Star Catalog. Our primary goal is to determine the binary frequency

among those in the cluster/association, field, and runaway groups. The

results will help us assess the role of binaries in massive star

formation and in the processes that lead to the ejection of massive

stars from their natal clusters. The program will also lead to the

identification of new, close binaries that will be targets of long term

spectroscopic and high angular resolution observations to determine

their masses and distances. The results will also be important for the

interpretation of the spectra of suspected and newly identified binary

and multiple systems.

 

FGS 11213

 

Distances to Eclipsing M Dwarf Binaries

 

We propose HST FGS observations to measure accurate distances of 5

nearby M dwarf eclipsing binary systems, from which model-independent

luminosities can be calculated. These objects have either poor or no

existing parallax measurements. FGS parallax determinations for these

systems, with their existing dynamic masses determined to better than

0.5%, would serve as model-independent anchor points for the low-mass

end of the mass-luminosity diagram.

 

NIC1/NIC2/NIC3 11319

 

NICMOS Photometric Stability Monitoring

 

This NICMOS calibration proposal carries out photometric monitoring

observations during Cycle 15. The format is the same as the Cycle 14

version of the program (10725), but a few modifications were made with

respect to the Cycle 12 program 9995 and Cycle 13 program 10381.

Provisions had to be made to adopt to 2-gyro mode (G191B2B was added as

extra target to provide target visibility through most of the year).

Where before 4 or 7 dithers were made in a filter before we moved to the

next filter, now we observe all filters at one position before moving to

the next dither position. While the previous method was chosen to

minimize the effect of persistence, we now realize that persistence may

be connected to charge trapping and by moving through the filter such

that the count rate increases, we reach equilibrium more quickly between

charge being trapped and released. We have also increased exposure times

where possible to reduce the charge trapping non-linearity effects.

 

NIC1/NIC2/NIC3 11330

 

NICMOS Cycle 16 Extended Dark

 

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

 

NIC1/NIC2/NIC3 8795

 

NICMOS Post-SAA Calibration - CR Persistence Part 6

 

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 i

mages. Each observation will need its own CRMAP, as different SAA

passages leave different imprints on the NICMOS detectors.

 

NIC3 11545

 

A NICMOS Survey of Newly-Discovered Young Massive Clusters

 

We are on the cusp of a revolution in massive star research triggered by

2MASS and Spitzer/GLIMPSE, and now is the ideal time to capitalize on

these projects by performing the first survey of massive stars in young

stellar clusters throughout the Galactic plane. A search of the 2MASS

and GLIMPSE surveys has produced over 450 newly-identified massive

stellar cluster candidates in the Galactic plane which are hidden from

our view at optical wavelengths due to extinction. Here we propose a

program of 29 orbits to image the most promising candidate clusters in

broad and narrow band filters using HST/NICMOS. We will be complementing

these observations with approved Spitzer and Chandra programs,

numerous approved and planned ground-based spectroscopic observations,

and state-of-the-art modeling. We expect to substantially increase the

numbers of massive stars known in the Galaxy, including main sequence OB

stars and post-main sequence stars in the Red Supergiant, Luminous Blue

Variable and Wolf-Rayet stages. Ultimately, this program will address

many of the fundamental topics in astrophysics: the slope to the initial

mass function (IMF), an upper-limit to the masses of stars, the

formation and evolution of the most massive stars, gamma-ray burst (GRB)

progenitors, the chemical enrichment of the interstellar medium, and

nature of the first stars in the Universe.

 

WFPC2 11029

 

WFPC2 CYCLE 15 Intflat Linearity Check and Filter Rotation Anomaly

Monitor

 

Intflat observations will be taken to provide a linearity check: the

linearity test consists of a series of intflats in F555W, in each gain

and each shutter. A combination of intflats, visflats, and earthflats

will be used to check the repeatability of filter wheel motions.

{Intflat sequences tied to decons, visits 1-18 in prop 10363, have been

moved to the cycle 15 decon proposal xxxx for easier scheduling.} Note:

long-exposure WFPC2 intflats must be scheduled during ACS anneals to

prevent stray light from the WFPC2 lamps from contaminating long ACS

external exposures.

 

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 11312

 

The Local Cluster Substructure Survey {LoCuSS}: Deep Strong Lensing

Observations with WFPC2

 

LoCuSS is a systematic and detailed investigation of the mass,

substructure, and thermodynamics of 100 X-ray luminous galaxy clusters

at 0.15<z<0.3. The primary goal is to test our recent suggestion that

this population is dominated by dynamically immature disturbed clusters,

and that the observed mass-temperature relation suffers strong

structural segregation. If confirmed, this would represent a paradigm

shift in our observational understanding of clusters, that were hitherto

believed to be dominated by mature, undisturbed systems. We propose to

complete our successful Cycle 15 program {SNAP:10881} which prior to

premature termination had delivered robust weak-lensing detections in 17

clusters, and candidate strongly-lensed arcs in 11 of these 17. These

strong and weak lensing signals will give an accurate measure of the

total mass and structure of the dark matter distribution that we will

subsequently compare with X-ray and Sunyaev Zeldovich Effect

observables. The broader applications of our project include 1} the

calibration of mass-temperature and mass-SZE scaling relations which

will be critical for the calibration of proposed dark energy

experiments, and 2} the low redshift baseline study of the demographics

of massive clusters to aid interpretation of future high redshift {z>1}

cluster samples. To complete the all-important high resolution imaging

component of our survey, we request deep WFPC2 observations of 20

clusters through the F606W filter, for which wide-field weak-lensing

data are already available from our Subaru imaging program. The

combination of deep WFPC2 and Subaru data for these 20 clusters will

enable us to achieve the science program approved by the Cycle 15 TAC.

 

WFPC2 11794

 

Cycle 16 Visible Earth Flats

 

This proposal monitors flatfield stability. This proposal obtains

sequences of Earth streak flats to construct high quality flat fields

for the WFPC2 filter set. These flat fields will allow mapping of the

OTA illumination pattern and will be used in conjunction with previous

internal and external flats to generate new pipeline superflats. These

Earth flats will complement the Earth flat data obtained during cycles

4-15.

 

WFPC2 11797

 

Supplemental WFPC2 CYCLE 16 Intflat Linearity Check and Filter Rotation

Anomaly Monitor

 

Supplemental observations to 11029, to cover period from Aug 08 to SM4.

Intflat observations will be taken to provide a linearity check: the

linearity test consists of a series of intflats in F555W, in each gain

and each shutter. A combination of intflats, visflats, and earthflats

will be used to check the repeatability of filter wheel motions.

(Intflat sequences tied to decons, visits 1-18 in prop 10363, have been

moved to the cycle 15 decon proposal 11022 for easier scheduling.)

 

Note: long-exposure WFPC2 intflats must be scheduled during ACS anneals

to prevent stray light from the WFPC2 lamps from contaminating long ACS

external exposures.

 

Note: These are supplemental observations to cover June to SM4 (Oct 8

'08) + 6 months.

 

FLIGHT OPERATIONS SUMMARY:

 

Significant Spacecraft Anomalies: (The following are preliminary reports

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

 

HSTARS:

 

11371 GSAcq(1,2,2) failed to RGA Hold (Gyro Control) in LOS @ 183/20:31z

GSAcq @183/20:20:27z and subsequent REAcq @21:58:30z failed to RGA Hold

with (QF1SRLEX), (QF1STOPF) indication flags set on FGS-1. Received 486

ESB "a07" (FGS CT failed-Timeout for data valid FGS-1) @183/20:31 &

22:08z. Possible obs affected: NICMOS 137-145,  Proposal ID#11545.

 

11372 Two REAcqs(2,1,2) failed due to Scan Step Limit Exceeded on FGS 2

@ 184/04:44:03z & 06:19:47z 

GSAcq @184/03:06:23 was successful. REAcqs(2,1,2) @04:40:34z and 06:16z

failed to RGA hold due to scan step limit exceeded on FGS 2. Received

QF2SSLEX and QF2STOPF stop flags. Possible obs affected: NICMOS #157-160,

Proposal #11135 & # 11330.

 

 

COMPLETED OPS REQUEST: (None)

 

COMPLETED OPS NOTES: (None)

 

                               SCHEDULED      SUCCESSFUL     

FGS GSacq                       08                   07                 

FGS REacq                       05                   02   

OBAD with Maneuver         26                   26

 

SIGNIFICANT EVENTS: (None)