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Daily Report #4517



 
 
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Old January 2nd 08, 02:18 PM posted to sci.astro.hubble
Cooper, Joe
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Default Daily Report #4517

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT****** # 4517

PERIOD COVERED: UT Dec 31 - Jan 01, 2007 (DOY 365) - 2008 (DOY 001)

OBSERVATIONS SCHEDULED

ACS/SBC 11145

Probing the Planet Forming Region of T Tauri Stars in Chamaeleon

By studying the inner, planet-forming regions of circumstellar disks
around low-mass pre- main sequence stars we can refine theories of
giant planet formation and develop timescales for the evolution of
disks and their planets. Spitzer infrared observations of T Tauri
stars in the Chamaeleon star-forming region have given us an
unprecedented look at dust evolution in young objects. However,
despite this ground breaking progress in studying the dust in young
disks, the gas properties of the inner disk remain essentially
unknown. Using ACS on HST, we propose to measure the H_2 emission
originating in the innermost disk regions of classical T Tauri stars
in different stages of evolution with the objective of revealing the
timescales of gas dissipation and its relationship to dust evolution.
This proposal is part of a comprehensive effort with approved programs
on Spitzer, Gemini, and Magellan that aim to characterize the state of
gas and dust in disks where planets may already have formed.

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.

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 {R26} 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 10890

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

The formative phase 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,
restricting us to the study of 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 bright at mid-IR wavelengths
{F[24um]0.8mJy}, but deep ground based imaging suggests extremely
faint {and in some cases extended} optical counterparts {R~24-27}.
Deep K-band images show barely resolved galaxies. Mid-infrared
spectroscopy with Spitzer/IRS reveals that they have redshifts z ~
2-2.5, suggesting bolometric luminosities ~10^{13-14}Lsun! We propose
to obtain deep ACS F814W and NIC2 F160W images of these sources and
their environs in order to determine kpc-scale morphologies and
surface photometry for these galaxies. The proposed observations will
help us determine whether these extreme 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 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 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.

WFPC2 11327

Red leaks

The aim of this program is to measure the red leaks in the 8 WFPC2
UV??? filters (F122M, F300W, F255W, F218W, F185W, F170W, F160BW,
F122M). We will use red crossing filters to isolate and directly
measure the leaks. No observations of this kind have ever been
performed with WFPC2 to check the red leaks in the UV filters, most of
them being extensively used by GO/GTO programs. A previous calibration
program has only imaged spectrophotometric standard stars with UV
filters (no filter crossing) thus the red leak is hard to measure
using this data. The throughput curves for some of the UV filters
(F300W, F255W, F218W, F185W) in synphot have incomplete information,
some of them have gaps in the measurements as wide as 3000A.

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.

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 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 11166

The Mass-dependent Evolution of the Black Hole-Bulge Relations

In the local universe, the masses of giant black holes are correlated
with the luminosities, masses and velocity dispersions of their host
galaxy bulges. This indicates a surprisingly close connection between
the evolution of galactic nuclei (on parsec scales) and of stars on
kpc scales. A key observational test of proposed explanations for
these correlations is to measure how they have evolved over cosmic
time. Our ACS imaging of 20 Seyfert 1 galaxies at z=0.37 showed them
to have smaller bulges (by a factor of 3) for a given central black
hole mass than is found in galaxies in the present-day universe.
However, since all our sample galaxies had black hole masses in the
range 10^8.0--8.5 Msun, we could only measure the OFFSET in black hole
mass to bulge luminosity ratios from the present epoch. By extending
this study to black hole masses another factor of 10 lower, we propose
to determine the full CORRELATION of black hole mass with host galaxy
properties at a lookback time of 4 Gyrs and to test mass-dependency of
the evolution. We have selected 14 Seyfert galaxies from SDSS DR5
whose narrow Hbeta emission lines (and estimated nuclear luminosities)
imply that they have black hole masses around 10^7 Msuns. We will soon
complete our Keck spectroscopic measures of their bulge velocity
dispersions. We need a 1-orbit NICMOS image of each galaxy to separate
its nonstellar luminosity from its bulge and disk. This will allow us
to make the first determination of the full black hole/bulge relations
at z=0.37 (e.g. M-L and M-sigma), as well as a test of whether active
galaxies obey the Fundamental Plane relation at that epoch.

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 {R26} 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 11027

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
4-14.

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 11202

The Structure of Early-type Galaxies: 0.1-100 Effective Radii

The structure, formation and evolution of early-type galaxies is still
largely an open problem in cosmology: how does the Universe evolve
from large linear scales dominated by dark matter to the highly
non-linear scales of galaxies, where baryons and dark matter both play
important, interacting, roles? To understand the complex physical
processes involved in their formation scenario, and why they have the
tight scaling relations that we observe today {e.g. the Fundamental
Plane}, it is critically important not only to understand their
stellar structure, but also their dark-matter distribution from the
smallest to the largest scales. Over the last three years the SLACS
collaboration has developed a toolbox to tackle these issues in a
unique and encompassing way by combining new non-parametric strong
lensing techniques, stellar dynamics, and most recently weak
gravitational lensing, with high-quality Hubble Space Telescope
imaging and VLT/Keck spectroscopic data of early-type lens systems.
This allows us to break degeneracies that are inherent to each of
these techniques separately and probe the mass structure of early-type
galaxies from 0.1 to 100 effective radii. The large dynamic range to
which lensing is sensitive allows us both to probe the clumpy
substructure of these galaxies, as well as their low-density outer
haloes. These methods have convincingly been demonstrated, by our
team, using smaller pilot-samples of SLACS lens systems with HST data.
In this proposal, we request observing time with WFPC2 and NICMOS to
observe 53 strong lens systems from SLACS, to obtain complete
multi-color imaging for each system. This would bring the total number
of SLACS lens systems to 87 with completed HST imaging and effectively
doubles the known number of galaxy-scale strong lenses. The deep HST
images enable us to fully exploit our new techniques, beat down
low-number statistics, and probe the structure and evolution of
early-type galaxies, not only with a uniform data-set an order of
magnitude larger than what is available now, but also with a fully
coherent and self-consistent methodological approach!

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************** 14**************** 14
FGS REacq************** 15**************** 15
OBAD with Maneuver **** 58**************** 58

SIGNIFICANT EVENTS: (None)


 




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