HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT      # 4529

PERIOD COVERED: UT January 017, 2008 (DOY 017)

OBSERVATIONS SCHEDULED

ACS/SBC 11162

Understanding the Long Term Impacts of Low Magnetic Accretion

The low accretion rate Polar EF Eri has been in a low state for more

than 9 years. Our recent GALEX photometry revealed a source of UV light

that is producing more flux than the white dwarf and which is highly

modulated on the 81 min orbital period of the system. We request UV

spectra with the SBC on the ACS to resolve whether limb darkening or

cyclotron emission can explain the observed phenomena and provide

insight on the long term heating effects under low accretion scenarios.

FGS 11211

An Astrometric Calibration of Population II Distance Indicators

In 2002 HST produced a highly precise parallax for RR Lyrae. That

measurement resulted in an absolute magnitude, M{V}= 0.61+/-0.11, a

useful result, judged by the over ten refereed citations each year

since. It is, however, unsatisfactory to have the direct,

parallax-based, distance scale of Population II variables based on a

single star. We propose, therefore, to obtain the parallaxes of four

additional RR Lyrae stars and two Population II Cepheids, or W Vir

stars. The Population II Cepheids lie with the RR Lyrae stars on a

common K-band Period-Luminosity relation. Using these parallaxes to

inform that relationship, we anticipate a zero-point error of 0.04

magnitude. This result should greatly strengthen confidence in the

Population II distance scale and increase our understanding of RR Lyrae

star and Pop II Cepheid astrophysics.

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.

NIC2 11341

Lower Luminosity AGNs at Cosmologically Interesting Redshifts: SEDs and

Accretion Rates of z~0.36 Seyferts

We propose a multiwavelength campaign to constrain the SEDs of Seyferts

at z~0.36. This epoch, corresponding to a look back time of 4 Gyrs, is

cosmologically interesting for studies of the coeval development of

black holes and their host galaxy bulges. Our sample, comprising 24

Seyferts, has unprecedented high quality Keck spectroscopy and HST

imaging already invested to extract host galaxy bulge properties,

estimate black hole masses, and separate nuclear and host optical

luminosities. To supplement and extend this successful program, we

request 93 ks of Chandra time (to measure the shape and power of the

AGN-only X-ray continuum), 11 hrs each of Spitzer and Gemini (to

constrain the dust temperature), and 7 orbits of HST (to determine the

nuclear luminosity for the final 7 objects).

NIC3 11153

The Physical Nature and Age of Lyman Alpha Galaxies

In the simplest scenario, strong Lyman alpha emission from high redshift

galaxies would indicate that stellar populations younger than 10 Myrs

dominate the UV. This does not, however, constrain the stellar

populations older than 100 Myrs, which do not contribute to UV light.

Also, the Lyman alpha line can be boosted if the interstellar medium is

both clumpy and dusty. Different studies with small samples have reached

different conclusions about the presence of dust and old stellar

populations in Lyman alpha emitters. We propose HST- NICMOS and

Spitzer-IRAC photometry of 35 Lyman-alpha galaxies at redshift

4.5<z<6.5, in order to determine their spectral energy distribution

{SED} extending through rest-frame optical. This will allow us to

measure accurately {1} The total stellar mass in these objects,

including old stars which may have formed at redshifts {z > 8} not

easily probed by any other means. {2} The dust extinction in the

rest-frame UV, and therefore a correction to their present

star-formation rates. Taken together, these two quantities will yield

the star-formation histories of Lyman alpha galaxies, which form fully

half of the known galaxies at z=4-6. They will tell us whether these are

young or old galaxies by straddling the 4000A break. Data from NICMOS is

essential for these compact and faint {i=25-26th magnitude AB} high

redshift galaxies, which are too faint for good near-IR photometry from

the ground.

NIC3 11195

Morphologies of the Most Extreme High-Redshift Mid-IR-luminous Galaxies

II: The `Bump' Sources

The formative phase of some of the most massive galaxies may be

extremely luminous, characterized by intense star- and AGN-formation.

Till now, few such galaxies have been unambiguously identified at high

redshift, and thus far we have been restricted to studying the

low-redshift ultraluminous infrared galaxies as possible analogs. We

have recently discovered a sample of objects which may indeed represent

this early phase in galaxy formation, and are undertaking an extensive

multiwavelength study of this population. These objects are optically

extremely faint {R>26} but nevertheless bright at mid-infrared

wavelengths {F[24um] > 0.5 mJy}. Mid-infrared spectroscopy with

Spitzer/IRS reveals that they have redshifts z~2, implying luminosities

~1E13 Lsun. Their mid-IR SEDs fall into two broad, perhaps overlapping,

categories. Sources with brighter F[24um] exhibit power-law SEDs and SiO

absorption features in their mid-IR spectra characteristic of AGN,

whereas those with fainter F[24um] show a "bump" characteristic of the

redshifted 1.6um peak from a stellar population, and PAH emission

characteristic of starformation. We have begun obtaining HST images of

the brighter sources in Cycle 15 to obtain identifications and determine

kpc-scale morphologies for these galaxies. Here, we aim to target the

second class {the "bump" sources} with the goal of determining if these

constitute morphologically different objects, or simply a "low-AGN"

state of the brighter class. The proposed observations will help us

determine whether these objects are merging systems, massive obscured

starbursts {with obscuration on kpc scales!} or very reddened {locally

obscured} AGN hosted by intrinsically low-luminosity galaxies.

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 11178

Probing Solar System History with Orbits, Masses, and Colors of

Transneptunian Binaries

The recent discovery of numerous transneptunian binaries {TNBs} opens a

window into dynamical conditions in the protoplanetary disk where they

formed as well as the history of subsequent events which sculpted the

outer Solar System and emplaced them onto their present day heliocentric

orbits. To date, at least 47 TNBs have been discovered, but only about a

dozen have had their mutual orbits and separate colors determined,

frustrating their use to investigate numerous important scientific

questions. The current shortage of data especially cripples scientific

investigations requiring statistical comparisons among the ensemble

characteristics. We propose to obtain sufficient astrometry and

photometry of 23 TNBs to compute their mutual orbits and system masses

and to determine separate primary and secondary colors, roughly tripling

the sample for which this information is known, as well as extending it

to include systems of two near-equal size bodies. To make the most

efficient possible use of HST, we will use a Monte Carlo technique to

optimally schedule our observations.

WFPC2 11198

Pure Parallel Imaging in the NDWFS Bootes Field

The NOAO Deep-Wide Field Survey {NDWFS} Bootes field is the target of

one of the most extensive multiwavelength campaigns in astronomy. In

addition to ground-based optical and near-infrared imaging, deep radio

mapping, and extensive spectroscopy, this entire region has been imaged

by the Chandra, Spitzer {IRAC and MIPS}, and GALEX missions. Robust

photometric redshifts {calibrated using over 20,000 spectroscopic

redshifts} exist for all sources brighter than R=24.5 or than 13 uJy at

4.5 microns. To enhance the value of this data set, we propose pure

parallel observations for all approved Cycle 16 programs in this region

that lack coordinated parallel observations. The primary aim of this

program will be to provide a database useful for the broad range of

science programs underway in this region.

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 11020

Cycle 15 Focus Monitor

The focus of HST is measured primarily with ACS/HRC over full CVZ orbits

to obtain accurate mean focus values via a well sampled breathing curve.

Coma and astigmatism are also determined from the same data in order to

further understand orbital effects on image quality and optical

alignments. To monitor the stability of ACS to WFPC2 relative focii,

we've carried over from previous focus monitor programs parallel

observations taken with the two cameras at suitable orientations of

previously observed targets, and interspersed them with the HRC CVZ

visits.

FLIGHT OPERATIONS SUMMARY:

Significant Spacecraft Anomalies: (The following are preliminary reports

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

HSTARS:

11148 - GSacq(1,2,1) failed, Search Radius Limit exceeded on FGS 1

           GSacq(1,2,1) at 018/05:53:16 failed at 05:58:16 with search radius limit

           exceeded on FGS 1. One 486 status buffer "A05" message (FGS Coarse Track

           failed- Search Radius Limit exceeded) was received. OBAD prior to GSACQ

           had RSS error of 523.43 arcseconds.

           REacq(1,2,1) at 07:21:00 was successful

11149 - Loss of Lock while LOS

           Analysis of engineering recorder data indicates a Loss of Lock occurred

           at 017/08:37:05 while vehicle was LOS. QF1STOPF and QF2STOPF flags were

           observed to be set at acquisition of signal at 09:47:21. Term EXP

           command was not until 08:41:20. A type 3 slew was in progress at the

           time.

COMPLETED OPS REQUEST: (None)

COMPLETED OPS NOTES: (None)

                      SCHEDULED      SUCCESSFUL      FAILURE TIMES

FGS GSacq               08                 07           

FGS REacq               07                 07                  

OBAD with Maneuver 28                 28               

LOSS of LOCK                                                    017/0837z

SIGNIFICANT EVENTS: (None)