HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

 

DAILY REPORT       #4739

 

PERIOD COVERED: 5am November 17 - 5am November 18, 2008 (DOY

                           322/1000z-323/1000z)

 

OBSERVATIONS SCHEDULED

 

WFPC2 10880

 

The Host Galaxies of QSO2s: AGN Feeding and Evolution at High

Luminosities

 

Now that the presence of supermassive black holes in the nuclei of

galaxies is a well established fact, other questions related to the AGN

phenomena still have to be answered. Problems of particular interest are

how the AGN gets fed, how the black hole evolves and how the evolution

of the black hole is related to the evolution of the galaxy bulge. Here

we propose to address some of these issues using ACS/WFC + F775W

snapshot images of 73 QSO2s with redshifts in the range 0.3<z<0.4. These

observations will be combined with similar archival data of QSO1s and

ground based data of Seyfert and normal galaxies. First, we will

investigate whether interactions are the most important feeding

mechanism in high luminosity AGNs. This will be done in a quantitative

way, comparing the asymmetry indices of QSO2 hosts with those of lower

luminosity AGNs and normal galaxies. Second, we will do a detailed study

of the morphology of the host galaxies of both QSO types, to determine

if they are similar, or if there is an evolutionary trend from QSO2s to

QSO1s. The results from this project will represent an important step in

the understanding of AGN evolution, and may also introduce a substantial

modification to the Unified Model.

 

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.

 

WFPC2 11113

 

Binaries in the Kuiper Belt: Probes of Solar System Formation and

Evolution

 

The discovery of binaries in the Kuiper Belt and related small body

populations is powering a revolutionary step forward in the study of

this remote region. Three quarters of the known binaries in the Kuiper

Belt have been discovered with HST, most by our snapshot surveys. The

statistics derived from this work are beginning to yield surprising and

unexpected results. We have found a strong concentration of binaries

among low-inclination Classicals, a possible size cutoff to binaries

among the Centaurs, an apparent preference for nearly equal mass

binaries, and a strong increase in the number of binaries at small

separations. We propose to continue this successful program in Cycle 16;

we expect to discover at least 13 new binary systems, targeted to

subgroups where these discoveries can have the greatest impact.

 

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.

 

WFPC2 11289

 

SL2S: The Strong Lensing Legacy Survey

 

Recent systematic surveys of strong galaxy-galaxy lenses {CLASS, SLACS,

GOODS, etc.} are producing spectacular results for galaxy masses roughly

below a transition mass M~10^13 Mo. The observed lens properties and

their evolution up to z~0.2, consistent with numerical simulations, can

be described by isothermal elliptical potentials. In contrast, modeling

of giant arcs in X-ray luminous clusters {halo masses M >~10^13 Mo}

favors NFW mass profiles, suggesting that dark matter halos are not

significantly affected by baryon cooling. Until recently, lensing

surveys were neither deep nor extended enough to probe the intermediate

mass density regime, which is fundamental for understanding the assembly

of structures. The CFHT Legacy Survey now covers 125 square degrees, and

thus offers a large reservoir of strong lenses probing a large range of

mass densities up to z~1. We have extracted a list of 150 strong lenses

using the most recent CFHTLS data release via automated procedures.

Following our first SNAPSHOT proposal in cycle 15, we propose to

continue the Hubble follow-up targeting a larger list of 130 lensing

candidates. These are intermediate mass range candidates {between

galaxies and clusters} that are selected in the redshift range of 0.2-1

with no a priori X-ray selection. The HST resolution is necessary for

confirming the lensing candidates, accurate modeling of the lenses, and

probing the total mass concentration in galaxy groups up to z~1 with the

largest unbiased sample available to date.

 

WFPC2 11612

 

Eta Carinae's Continuing Instability and Recovery - the 2009 Event

 

Eta Carinae is the only really observable example of structural recovery

from a massive giant eruption, a "supernova imposter' event. Moreover it

is the only well-observed star above 100 Msun, and its

5.5-year-recurrent spectroscopic events provide extraordinary clues to

its surface instability. This truly unique combination of attributes

makes it valuable for understanding the most massive stars. A fresh

development arose a few years ago: The star has brightened much faster

than before, and appears to have entered a rapid stage in its

post-eruption recovery.

 

A spectroscopic event will occur at 2009.0, soon after the planned HST

servicing mission. Because of the recent secular trend, this event is

expected to differ from its well-observed 2003.5 predecessor. The

differences will be very important, because they offer clues to

very-massive-star structural instabilities that can't be observed in any

other known way.

 

Some of the needed observations require HST's high spatial resolution

and UV coverage. We propose an efficient, well-chosen set of STIS and

ACS observations around the critical time. If the servicing mission is

too late for the event, then a subset of the observations will still be

merited.

 

FLIGHT OPERATIONS SUMMARY:

 

Significant Spacecraft Anomalies: (The following are preliminary reports

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

 

HSTARS:

11576 - GSacq 1,2,1 Failed: Search Radius Limit Exceeded

           GSacq 1,2,1 at 322/12:42:12 failed due to search radius limit exceeded

           at 12:47:20. ESB message A05 (Exceeded Search Radius Limit) was

           received.

 

           Observations affected: WFPC 21, 22, 23,  proposal # 11289

 

 

COMPLETED OPS REQUEST:

18364-1 - NCS Restart and Cooldown (ongoing)

18366-0 - Place +BB SPA Trim Relay Back On-Line @ 322/1610z

 

 

COMPLETED OPS NOTES: (None)

 

 

                      SCHEDULED      SUCCESSFUL

FGS GSacq               15                 14     

FGS REacq               00                 00            

OBAD with Maneuver 30                 30          

 

SIGNIFICANT EVENTS:

 

Flash Report NCS CPL Operations:

The NCS CPL restart accomplished successfully. The CPL is running with a

setpoint of +12 degC.

 

 

Flash Report: +BB SPA On-Line

At approximately 2008/322 16:09 GMT via Ops Request 18366-0, the +BB SPA

trim relay was placed back on-line in FSW with hardware verification of

the +BB SPA closure at 18:00 GMT.