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)