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Daily Report #5134



 
 
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Old July 9th 10, 03:58 PM posted to sci.astro.hubble
Cooper, Joe
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Posts: 568
Default Daily Report #5134

HUBBLE SPACE TELESCOPE - Continuing to Collect World Class Science

DAILY REPORT #5134

PERIOD COVERED: 5am July 8 - 5am July 9, 2010 (DOY 189/09:00z-190/09:00z)

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 5 5
FGS REAcq 7 7
OBAD with Maneuver 4 4

SIGNIFICANT EVENTS: (None)

OBSERVATIONS SCHEDULED:

COS/FUV/STIS/CCD/MA1 11592

Testing the Origin(s) of the Highly Ionized High-Velocity Clouds: A
Survey of Galactic Halo Stars at z3 kpc

Cosmological simulation predicts that highly ionized gas plays an
important role in the formation and evolution of galaxies and their
interplay with the intergalactic medium. The NASA HST and FUSE
missions have revealed high-velocity CIV and OVI absorption along
extragalactic sightlines through the Galactic halo. These highly
ionized high-velocity clouds (HVCs) could cover 85% of the sky and
have a detection rate higher than the HI HVCs. Two competing, equally
exciting, theories may explain the origin of these highly ionized
HVCs: 1) the "Galactic" theory, where the HVCs are the result of
feedback processes and trace the disk-halo mass exchange, perhaps
including the accretion of matter condensing from an extended corona;
2) the "Local Group" theory, where they are part of the local warm-hot
intergalactic medium, representing some of the missing baryonic matter
of the Universe. Only direct distance determinations can discriminate
between these models. Our group has found that some of these highly
ionized HVCs have a Galactic origin, based on STIS observations of one
star at z5.3 kpc. We propose an HST FUV spectral survey to search for
and characterize the high velocity NV, CIV, and SiIV interstellar
absorption toward 24 stars at much larger distances than any previous
searches (4d21 kpc, 3|z|13 kpc). COS will provide atomic to highly
ionized species (e.g.,OI, CII, CIV, SiIV) that can be observed at
sufficient resolution (R~22, 000) to not only detect these highly
ionized HVCs but also to model their properties and understand their
physics and origins. This survey is only possible because of the high
sensitivity of COS in the FUV spectral range.

COS/NUV/FUV 11598

How Galaxies Acquire their Gas: A Map of Multiphase Accretion and
Feedback in Gaseous Galaxy Halos

We propose to address two of the biggest open questions in galaxy
formation - how galaxies acquire their gas and how they return it to
the IGM - with a concentrated COS survey of diffuse multiphase gas in
the halos of SDSS galaxies at z = 0.15 - 0.35. Our chief science goal
is to establish a basic set of observational facts about the physical
state, metallicity, and kinematics of halo gas, including the sky
covering fraction of hot and cold material, the metallicity of infall
and outflow, and correlations with galaxy stellar mass, type, and
color - all as a function of impact parameter from 10 - 150 kpc.
Theory suggests that the bimodality of galaxy colors, the shape of the
luminosity function, and the mass-metallicity relation are all
influenced at a fundamental level by accretion and feedback, yet these
gas processes are poorly understood and cannot be predicted robustly
from first principles. We lack even a basic observational assessment
of the multiphase gaseous content of galaxy halos on 100 kpc scales,
and we do not know how these processes vary with galaxy properties.
This ignorance is presently one of the key impediments to
understanding galaxy formation in general. We propose to use the
high-resolution gratings G130M and G160M on the Cosmic Origins
Spectrograph to obtain sensitive column density measurements of a
comprehensive suite of multiphase ions in the spectra of 43 z 1 QSOs
lying behind 43 galaxies selected from the Sloan Digital Sky Survey.
In aggregate, these sightlines will constitute a statistically sound
map of the physical state and metallicity of gaseous halos, and
subsets of the data with cuts on galaxy mass, color, and SFR will seek
out predicted variations of gas properties with galaxy properties. Our
interpretation of these data will be aided by state-of-the-art
hydrodynamic simulations of accretion and feedback, in turn providing
information to refine and test such models. We will also use Keck,
MMT, and Magellan (as needed) to obtain optical spectra of the QSOs to
measure cold gas with Mg II, and optical spectra of the galaxies to
measure SFRs and to look for outflows. In addition to our other
science goals, these observations will help place the Milky Way's
population of multiphase, accreting High Velocity Clouds (HVCs) into a
global context by identifying analogous structures around other
galaxies. Our program is designed to make optimal use of the unique
capabilities of COS to address our science goals and also generate a
rich dataset of other absorption-line systems.

STIS/CC 11845

CCD Dark Monitor Part 2

Monitor the darks for the STIS CCD.

STIS/CC 11847

CCD Bias Monitor-Part 2

Monitor the bias in the 1x1, 1x2, 2x1, and 2x2 bin settings at gain=1,
and 1x1 at gain = 4, to build up high-S/N superbiases and track the
evolution of hot columns.

WFC3/IR 11694

Mapping the Interaction Between High-Redshift Galaxies and the
Intergalactic Environment

With the commissioning of the high-throughput large-area camera
WFC3/IR, it is possible for the first time to undertake an efficient
survey of the rest-frame optical morphologies of galaxies at the peak
epoch of star formation in the universe. We therefore propose deep
WFC3/IR imaging of over 320 spectroscopically confirmed galaxies
between redshift 1.6 z 3.4 in well-studied fields which lie along
the line of sight to bright background QSOs. The spectra of these
bright QSOs probe the IGM in the vicinity of each of the foreground
galaxies along the line of sight, providing detailed information on
the physical state of the gas at large galactocentric radii. In
combination with our densely sampled UV/IR spectroscopy, stellar
population models, and kinematic data in these fields, WFC3/IR imaging
data will permit us to construct a comprehensive picture of the
structure, dynamics, and star formation properties of a large
population of galaxies in the early universe and their effect upon
their cosmological environment.

WFC3/IR 11696

Infrared Survey of Star Formation Across Cosmic Time

We propose to use the unique power of WFC3 slitless spectroscopy to
measure the evolution of cosmic star formation from the end of the
reionization epoch at z6 to the close of the galaxy- building era at
z~0.3.Pure parallel observations with the grisms have proven to be
efficient for identifying line emission from galaxies across a broad
range of redshifts. The G102 grism on WFC3 was designed to extend this
capability to search for Ly-alpha emission from the first galaxies.
Using up to 250 orbits of pure parallel WFC3 spectroscopy, we will
observe about 40 deep (4-5 orbit) fields with the combination of G102
and G141, and about 20 shallow (2-3 orbit) fields with G141 alone.

Our primary science goals at the highest redshifts a (1) Detect Lya
in ~100 galaxies with z5.6 and measure the evolution of the Lya
luminosity function, independent of of cosmic variance; 2) Determine
the connection between emission line selected and continuum-break
selected galaxies at these high redshifts, and 3) Search for the
proposed signature of neutral hydrogen absorption at re-ionization. At
intermediate redshifts we will (4) Detect more than 1000 galaxies in
Halpha at 0.5z1.8 to measure the evolution of the
extinction-corrected star formation density across the peak epoch of
star formation. This is over an order-of-magnitude improvement in the
current statistics, from the NICMOS Parallel grism survey. (5) Trace
``cosmic downsizing" from 0.5z2.2; and (6) Estimate the evolution in
reddening and metallicty in star- forming galaxies and measure the
evolution of the Seyfert population. For hundreds of spectra we will
be able to measure one or even two line pair ratios -- in particular,
the Balmer decrement and [OII]/[OIII] are sensitive to gas reddening
and metallicity. As a bonus, the G102 grism offers the possibility of
detecting Lya emission at z=7-8.8.

To identify single-line Lya emitters, we will exploit the wide
0.8--1.9um wavelength coverage of the combined G102+G141 spectra. All
[OII] and [OIII] interlopers detected in G102 will be reliably
separated from true LAEs by the detection of at least one strong line
in the G141 spectrum, without the need for any ancillary data. We
waive all proprietary rights to our data and will make high-level data
products available through the ST/ECF.

WFC3/IR/ACS/WFC 11663

Formation and Evolution of Massive Galaxies in the Richest
Environments at 1.5 z 2.0

We propose to image seven 1.5z2 clusters and groups from the IRAC
Shallow Cluster Survey with WFC3 and ACS in order to study the
formation and evolution of massive galaxies in the richest
environments in the Universe in this important redshift range. We will
measure the evolution of the sizes and morphologies of massive cluster
galaxies, as a function of redshift, richness, radius and local
density. In combination with allocated Keck spectroscopy, we will
directly measure the dry merger fraction in these clusters, as well as
the evolution of Brightest Cluster Galaxies (BCGs) over this redshift
range where clear model predictions can be confronted. Finally we will
measure both the epoch of formation of the stellar populations and the
assembly history of that stellar mass, the two key parameters in the
modern galaxy formation paradigm.

WFC3/UV/ACS/WFC 11710

The Extreme Globular Cluster System of Abell 1689: The Ultimate Test
of Universal Formation Efficiency

The stellar masses of the most luminous galaxies poorly represent the
masses of the halos in which they reside. However, recent studies of
the very rich globular cluster (GC) populations in the centers of
galaxy clusters point toward an apparently linear scaling of the
number of GCs with the total core mass of the galaxy cluster. Thus,
unlike for the stars in cD galaxies, GC formation in these systems
appears to have proceeded with a roughly universal mass conversion
efficiency. GCs are also distinct in that their spatial distributions
are more extended than the starlight, and recent simulations suggest
that they follow the mass density profile of the merged dark matter
halos that formed stars at high redshift. To provide a definitive test
of the universal efficiency hypothesis requires measuring the number
of GCs in the most massive galaxy clusters, where the number should be
a factor of 5 or more greater than seen in M87. Likewise, the
relationship between GCs and mass density can only be tested in
systems where the total mass and mass density are well-determined.
Fortunately, the imaging power of HST brings the GC population of
Abell 1689, the most extreme high-mass lensing cluster, into range.
Estimates of the size of the A1689 GC population from available data
suggest an unprecedented 100, 000 GCs, but this number is based on the
tip of the iceberg and is extremely uncertain. We propose to obtain
the first accurate measurement of the number of GCs and their density
profile in this extraordinary system - the most massive and most
distant GC system ever studied - and thus make the ultimate test of
the universal GC formation hypothesis. Our deep I-band image will also
provide a stringent "null-detection" test of several known z7 galaxy
candidates and improve the mass model of the system by increasing the
number of usable lensed background galaxies. Finally, we will take
deep multi-band parallel observations with WFC3/IR to help in
quantifying the abundance of rare faint red objects.

WFC3/UVIS 11905

WFC3 UVIS CCD Daily Monitor

The behavior of the WFC3 UVIS CCD will be monitored daily with a set
of full-frame, four-amp bias and dark frames. A smaller set of 2Kx4K
subarray biases are acquired at less frequent intervals throughout the
cycle to support subarray science observations. The internals from
this proposal, along with those from the anneal procedure (Proposal
11909), will be used to generate the necessary superbias and superdark
reference files for the calibration pipeline (CDBS).

WFC3/UVIS/IR 11644

A Dynamical-Compositional Survey of the Kuiper Belt: A New Window Into
the Formation of the Outer Solar System

The eight planets overwhelmingly dominate the solar system by mass,
but their small numbers, coupled with their stochastic pasts, make it
impossible to construct a unique formation history from the dynamical
or compositional characteristics of them alone. In contrast, the huge
numbers of small bodies scattered throughout and even beyond the
planets, while insignificant by mass, provide an almost unlimited
number of probes of the statistical conditions, history, and
interactions in the solar system. To date, attempts to understand the
formation and evolution of the Kuiper Belt have largely been dynamical
simulations where a hypothesized starting condition is evolved under
the gravitational influence of the early giant planets and an attempt
is made to reproduce the current observed populations. With little
compositional information known for the real Kuiper Belt, the test
particles in the simulation are free to have any formation location
and history as long as they end at the correct point. Allowing
compositional information to guide and constrain the formation,
thermal, and collisional histories of these objects would add an
entire new dimension to our understanding of the evolution of the
outer solar system. While ground based compositional studies have hit
their flux limits already with only a few objects sampled, we propose
to exploit the new capabilities of WFC3 to perform the first ever
large-scale dynamical-compositional study of Kuiper Belt Objects
(KBOs) and their progeny to study the chemical, dynamical, and
collisional history of the region of the giant planets. The
sensitivity of the WFC3 observations will allow us to go up to two
magnitudes deeper than our ground based studies, allowing us the
capability of optimally selecting a target list for a large survey
rather than simply taking the few objects that can be measured, as we
have had to do to date. We have carefully constructed a sample of 120
objects which provides both overall breadth, for a general
understanding of these objects, plus a large enough number of objects
in the individual dynamical subclass to allow detailed comparison
between and within these groups. These objects will likely define the
core Kuiper Belt compositional sample for years to come. While we have
many specific results anticipated to come from this survey, as with
any project where the field is rich, our current knowledge level is
low, and a new instrument suddenly appears which can exploit vastly
larger segments of the population, the potential for discovery -- both
anticipated and not -- is extraordinary.


 




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