sci astro hubble http://groups google com/group/sci astro hubble?hl=en
sci astro hubble@googlegroups com
Today's topics:
============================================================================== TOPIC: Daily Report #5164
== 1 of 1 == Date: Fri, Aug 20 2010 6:06 am From: "Cooper, Joe"
HUBBLE SPACE TELESCOPE - Continuing to Collect World Class Science
DAILY REPORT #5164
PERIOD COVERED: 5am August 19 - 5am August 20, 2010 (DOY 231/09:00z-232/09:00z)
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 9 9 OBAD with Maneuver 3 3
SIGNIFICANT EVENTS: (None)
OBSERVATIONS SCHEDULED:
COS/NUV 11894
NUV Detector Dark Monitor
The purpose of this proposal is to measure the NUV detector dark rate by taking long science exposures with no light on the detector The detector dark rate and spatial distribution of counts will be compared to pre-launch and SMOV data in order to verify the nominal operation of the detector Variations of count rate as a function of orbital position will be analyzed to find dependence of dark rate on proximity to the SAA Dependence of dark rate as function of time will also be tracked
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/CCD 11845
CCD Dark Monitor Part 2
Monitor the darks for the STIS CCD
STIS/CCD 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
STIS/CCD/MA1/MA2 11569
Probing the Atomic and Molecular Inventory of a Beta-Pic Analog, the Young, Edge-On Debris Disk of HD32297
Edge-on, optically thin, debris disks provide unique opportunities to probe physical properties of the disk itself Using the host star as the background source, trace atomic and molecular disk species can be detected in absorption Redfield (2007) found that the recently discovered edge- on system, HD32297, has the strongest NaI absorption feature of any known debris disk, 5 times the level observed toward beta Pic, the canonical edge-on debris disk Roberge et al (2006) compiled the only comprehensive chemical inventory of a debris disk, using beta Pic, and found that carbon was surprisingly overabundant, which has important implications for the physical structure and support of a stable gas disk What is severely lacking are comparison observations to determine if such an abundance pattern is typical of debris disk systems HD32297 represents the best opportunity to make such a comparative study and perform a comprehensive gas inventory of a debris disk, due to its high NaI column density The UV is critical for this work due to the large number of strong transitions (almost 50 ions and molecules are accessible) that are located in, and often only in, the UV These observations will provide a much needed comparison dataset for addressing the gas chemistry of debris disk systems that are at the critical stage, near the end of planet formation, and in the process of clearing their interplanetary environments
STIS/CCD/MA1/MA2 11616
The Disks, Accretion, and Outflows (DAO) of T Tau Stars
Classical T Tauri stars undergo magnetospheric accretion, power outflows, and possess the physical and chemical conditions in their disks to give rise to planet formation Existing high resolution FUV spectra verify that this spectral region offers unique diagnostics of these processes, which have the potential to significantly advance our understanding of the interaction of a star and its accretion disk To date the limited results are intriguing, with dramatic differences in kinematic structure in lines ranging from C IV to H2 among the few stars that have been observed We propose to use HST/COS to survey the disks, outflows, and accretion (the DAO) of 26 CTTS and 6 WTTS in the FUV at high spectral resolution A survey of this size is essential to establish how properties of accretion shocks, winds and disk irradiation depend on disk accretion rate Specifically, our goals are to (1) measure the radiation from and understand the physical properties of the gas very near the accretion shock as a function of accretion rate using emission line profiles of hot lines (C IV, Si IV, N V, and He II); (2) measure the opacity, velocity, and temperature at the base of the outflow to constrain outflow models using wind absorption features; and (3) characterize the radiation incident on disks and protoplanetary atmospheres using H2 line and continuum emission and reconstructed bright Ly-alpha line emission
STIS/MA1/MA2 11857
STIS Cycle 17 MAMA Dark Monitor
This proposal monitors the behavior of the dark current in each of the MAMA detectors
The basic monitor takes two 1380s ACCUM darks each week with each detector However, starting Oct 5, pairs are only included for weeks that the LRP has external MAMA observations planned The weekly pairs of exposures for each detector are linked so that they are taken at opposite ends of the same SAA free interval This pairing of exposures will make it easier to separate long and short term temporal variability from temperature dependent changes
For both detectors, additional blocks of exposures are taken once every six months These are groups of five 1314s FUV-MAMA Time-Tag darks or five 3x315s NUV ACCUM darks distributed over a single SAA-free interval This will give more information on the brightness of the FUV MAMA dark current as a function of the amount of time that the HV has been on, and for the NUV MAMA will give a better measure of the short term temperature dependence
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 z>6 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 are: (1) Detect Lya
in ~100 galaxies with z>5
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
5 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 11926 IR Zero Points We will measure and monitor the zeropoints through the IR filters
using observations of the white dwarf standard stars, GD153, GD71 and
GD191B2B and the solar analog standard star, P330E
Data will be taken
monthly during Cycle 17
Observations of the star cluster, NGC 104,
are made twice to check color transformations
We expect an accuracy
of 2% in the wide filter zeropoints relative to the HST photometric
system, and 5% in the medium- and narrow-band filters
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
WFC3/UVIS/IR 11909 UVIS Hot Pixel Anneal The on-orbit radiation environment of WFC3 will continually generate
new hot pixels
This proposal performs the procedure required for
repairing those hot pixels in the UVIS CCDs
During an anneal, the
two-stage thermo-electric cooler (TEC) is turned off and the
four-stage TEC is used as a heater to bring the UVIS CCDs up to ~20
deg
C
As a result of the CCD warmup, a majority of the hot pixels
will be fixed; previous instruments such as WFPC2 and ACS have seen
repair rates of about 80%
Internal UVIS exposures are taken before
and after each anneal, to allow an assessment of the procedure's
effectiveness in WFC3, provide a check of bias, global dark current,
and hot pixel levels, as well as support hysteresis (bowtie)
monitoring and CDBS reference file generation
One IR dark is taken
after each anneal, to provide a check of the IR detector
==============================================================================
TOPIC: Daily Report #5165 == 1 of 1 ==
Date: Mon, Aug 23 2010 7:25 am
From: "Cooper, Joe" HUBBLE SPACE TELESCOPE - Continuing to Collect World Class Science DAILY REPORT #5165 PERIOD COVERED: 5am August 20 - 5am August 23, 2010 (DOY 232/09:00z-235/09:00z) FLIGHT OPERATIONS SUMMARY: Significant Spacecraft Anomalies: (The following are preliminary
reports of potential non-nominal performance that will be
investigated
) HSTARS: 12357 - GSAcq(1,2,1) at 233/21:37:49z Results in Fine-lock Back-up on
FGS1
Observations possibly affected: STIS 106-108 Proposal ID#11569 COMPLETED OPS REQUEST: (None) COMPLETED OPS NOTES: (None) FGS GSAcq 19 19
FGS REAcq 19 19
OBAD with Maneuver 16 16 SIGNIFICANT EVENTS: (None) OBSERVATIONS SCHEDULED: FGS 12320 The Ages of Globular Clusters and the Population II Distance Scale Globular clusters are the oldest objects in the universe whose age can
be accurately determined
The dominant error in globular cluster age
determinations is the uncertain Population II distance scale
We
propose to use FGS 1r to obtain parallaxes with an accuracy of 0
2
milliarcsecond for 9 main sequence stars with [Fe/H] < -1
5
This will
determine the absolute magnitude of these stars with accuracies of
0
04 to 0
06mag
This data will be used to determine the distance to
24 metal-poor globular clusters using main sequence fitting
These
distances (with errors of 0
05 mag) will be used to determine the ages
of globular clusters using the luminosity of the subgiant branch as an
age indicator
This will yield absolute ages with an accuracy 5%,
about a factor of two improvement over current estimates
Coupled with
existing parallaxes for more metal-rich stars, we will be able to
accurately determine the age for globular clusters over a wide range
of metallicities in order to study the early formation history of the
Milky Way and provide an independent estimate of the age of the
universe
The Hipparcos database contains only 1 star with [Fe/H] < -1
4 and an
absolute magnitude error less than 0
18 mag which is suitable for use
in main sequence fitting
Previous attempts at main sequence fitting
to metal-poor globular clusters have had to rely on theoretical
calibrations of the color of the main sequence
Our HST parallax
program will remove this source of possible systematic error and yield
distances to metal-poor globular clusters which are significantly more
accurate than possible with the current parallax data
The HST
parallax data will have errors which are 10 times smaller than the
current parallax data
Using the HST parallaxes, we will obtain main
sequence fitting distances to 11 globular clusters which contain over
500 RR Lyrae stars
This will allow us to calibrate the absolute
magnitude of RR Lyrae stars, a commonly used Population II distance
indicator
S/C 12046 COS FUV DCE Memory Dump Whenever the FUV detector high voltage is on, count rate and current
draw information is collected, monitored, and saved to DCE memory
Every 10 msec the detector samples the currents from the HV power
supplies (HVIA, HVIB) and the AUX power supply (AUXI)
The last 1000
samples are saved in memory, along with a histogram of the number of
occurrences of each current value
In the case of a HV transient (known as a "crackle" on FUSE), where
one of these currents exceeds a preset threshold for a persistence
time, the HV will shut down, and the DCE memory will be dumped and
examined as part of the recovery procedure
However, if the current
exceeds the threshold for less than the persistence time (a
"mini-crackle" in FUSE parlance), there is no way to know without
dumping DCE memory
By dumping and examining the histograms regularly,
we will be able to monitor any changes in the rate of "mini-crackles"
and thus learn something about the state of the detector
ACS/WFC 11996 CCD Daily Monitor (Part 3) This program comprises basic tests for measuring the read noise and
dark current of the ACS WFC and for tracking the growth of hot pixels
The recorded frames are used to create bias and dark reference images
for science data reduction and calibration
This program will be
executed four days per week (Mon, Wed, Fri, Sun) for the duration of
Cycle 17
To facilitate scheduling, this program is split into three
proposals
This proposal covers 308 orbits (19
25 weeks) from 21 June
2010 to 1 November 2010
WFC3/IR/S/C 11929 IR Dark Current Monitor Analyses of ground test data showed that dark current signals are more
reliably removed from science data using darks taken with the same
exposure sequences as the science data, than with a single dark
current image scaled by desired exposure time
Therefore, dark current
images must be collected using all sample sequences that will be used
in science observations
These observations will be used to monitor
changes in the dark current of the WFC3-IR channel on a day-to-day
basis, and to build calibration dark current ramps for each of the
sample sequences to be used by Gos in Cycle 17
For each sample
sequence/array size combination, a median ramp will be created and
delivered to the calibration database system (CDBS)
WFC3/UVIS/IR 11909 UVIS Hot Pixel Anneal The on-orbit radiation environment of WFC3 will continually generate
new hot pixels
This proposal performs the procedure required for
repairing those hot pixels in the UVIS CCDs
During an anneal, the
two-stage thermo-electric cooler (TEC) is turned off and the
four-stage TEC is used as a heater to bring the UVIS CCDs up to ~20
deg
C
As a result of the CCD warmup, a majority of the hot pixels
will be fixed; previous instruments such as WFPC2 and ACS have seen
repair rates of about 80%
Internal UVIS exposures are taken before
and after each anneal, to allow an assessment of the procedure's
effectiveness in WFC3, provide a check of bias, global dark current,
and hot pixel levels, as well as support hysteresis (bowtie)
monitoring and CDBS reference file generation
One IR dark is taken
after each anneal, to provide a check of the IR detector
WFC3/UVIS 11908 Cycle 17: UVIS Bowtie Monitor Ground testing revealed an intermittent hysteresis type effect in the
UVIS detector (both CCDs) at the level of ~1%, lasting hours to days
Initially found via an unexpected bowtie-shaped feature in flatfield
ratios, subsequent lab tests on similar e2v devices have since shown
that it is also present as simply an overall offset across the entire
CCD, i
e
, a QE offset without any discernable pattern
These lab
tests have further revealed that overexposing the detector to count
levels several times full well fills the traps and effectively
neutralizes the bowtie
Each visit in this proposal acquires a set of
three 3x3 binned internal flatfields: the first unsaturated image will
be used to detect any bowtie, the second, highly exposed image will
neutralize the bowtie if it is present, and the final image will allow
for verification that the bowtie is gone
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/UV 11904 UVIS Droplets To characterize the effects of the contamination (i
e
, droplets) on
the UVIS window, we will observe a star cluster in three wide band
filters (F225W, F555W, and F814W) as well as a narrow band filter
(F502N) and step the stars in the cluster across randomly located
droplets
The step size is 20 pixels, and we execute a five point line
dither for each filter
This should provide for observations both on
and off the droplets, for the same star
Internal flat fields are also
obtained, but, due to the high f/# of the internal calibration system,
the flats will be of limited utility, but will serve to map and
crudely track any changes in the droplets
The cluster needs to
contain both hot and cool stars, and therefore we select NGC 6752, a
nearby globular with a hot horizontal branch
Note, although the total
population of HB stars may be larger in systems such as NGC 2419, NGC
6715, and NGC 2808, those clusters are much further away and will not
provide a high density of stars over the global image (the droplets
are located over the entire frame)
There will be three visits
(initial, 7 days later, and 30 days later), with each visit requiring
4 orbits
The total program thus requires 12 orbits total
ACS/WFC3 11887 CCD Stability Monitor This program will verify that the low frequency flat fielding, the
photometry, and the geometric distortion are stable in time and across
the field of view of the CCD arrays
A moderately crowded stellar
field in the cluster 47 Tuc is observed with the ACS (at the cluster
core) and WFC3 (6 arcmin West of the cluster core) using the full
suite of broad and narrow band imaging filters
The positions and
magnitudes of objects will be used to monitor local and large scale
variations in the plate scale and the sensitivity of the detectors and
to derive an independent measure of the detector CTE
The UV
sensitivity for the SBC and ACS will be addressed in the UV
contamination monitor program (11886, PI=Smith)
One additional orbit will be obtained at the beginning of the cycle
will allow a verification of the CCD gain ratios for WFC3 using gain
2
0, 1
4, 1
0, 0
5 and for ACS using gain 4
0 and 2
0
In addition,
one subarray exposure with the WFC3 will allow a verification that
photometry obtained in full-frame and in sub-array modes are
repeatable to better than 1%
This test is important for the ACS
Photometric Cross-Calibration program (11889, PI=Bohlin) which uses
sub-array exposures
STIS/CCD 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
STIS/CCD 11845 CCD Dark Monitor Part 2 Monitor the darks for the STIS CCD
COS/NUV/FUV 11741 Probing Warm-Hot Intergalactic Gas at 0
5 < z < 1
3 with a Blind
Survey for O VI, Ne VIII, Mg X, and Si XII Absorption Systems Currently we can only account for half of the baryons (or less)
expected to be found in the nearby universe based on D/H and CMB
observations
This "missing baryons problem" is one of the
highest-priority challenges in observational extragalatic astronomy
Cosmological simulations suggest that the baryons are hidden in
low-density, shock-heated intergalactic gas in the log T = 5 - 7
range, but intensive UV and X-ray surveys using O VI, O VII, and O
VIII absorption lines have not yet confirmed this prediction
We
propose to use COS to carry out a sensitive survey for Ne VIII and Mg
X absorption in the spectra of nine QSOs at z(QSO) > 0
89
For the
three highest-redshift QSOs, we will also search for Si XII
This
survey will provide more robust constraints on the quantity of baryons
in warm-hot intergalactic gas at 0
5 < z < 1
3, and the data will
provide rich constraints on the metal enrichment, physical conditions,
and nature of a wide variety of QSO absorbers in addition to the
warm-hot systems
By comparing the results to other surveys at lower
redshifts (with STIS, FUSE, and from the COS GTO programs), the
project will also enable the first study of how these absorbers evolve
with redshift at z < 1
By combining the program with follow-up galaxy
redshift surveys, we will also push the study of galaxy-absorber
relationships to higher redshifts, with an emphasis on the
distribution of the WHIM with respect to the large-scale matter
distribution of the universe
WFC3/UVIS 11714 Snapshot Survey for Planetary Nebulae in Local Group Globular Clusters 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, four, 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 outside the Milky Way
These clusters, some of
which may be much younger than their counterparts in our galaxy, 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
This proposal continues a WFPC2 program started
in Cycle 16, but with the more powerful WFC3
As a by-product, the
survey will also produce color-magnitude diagrams for numerous
clusters for the first time, reaching down to the horizontal branch
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 z>6 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 are: (1) Detect Lya
in ~100 galaxies with z>5
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
5 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
5 STIS/CCD/MA 11660 Investigation Jet Rotation in Young Stars via High Resolution UV
Spectra In recent years we have successfully harnessed the high resolution of
STIS in the optical to reveal asymmetries in Doppler shifts transverse
to the flow direction in 8 T Tauri jets (Bacciotti ea 2002; Woitas ea
2005; Coffey ea 2004; 2007)
We interpret the findings, just 100 AU
above the disk, as signatures of jet rotation
The significance of
these results is considerable
They form the only existing
observational indications supporting the theory that jets extract
angular momentum from star-disk systems
Furthermore, they hold the
potential to discriminate between the main model contenders: X-wind
and Disk-wind (Ferreira ea 2006)
Although our results are
encouraging, it is evident that we are only marginally resolving the
effects of rotation because of the limiting resolution (spatially and
spectrally) of STIS in the optical
Therefore, in Cycle 12 we proposed
to extend this study into the near-ultraviolet (NUV), giving double
the spatial and spectral resolution (proposal ID 9807)
Unfortunately,
only 3 targets in our survey were observed before the failure of STIS
(Coffey ea 2007)
Nevertheless, the results were very exciting
Agreement was found between the optical and NUV results in terms of
the magnitude and sense of the Doppler shift gradient across the jet
Furthermore, the NUV lines indicated that the observed high velocity
gas was launched from about 0
2-0
5 AU, compared to the lower velocity
gas traced in optical lines which originates from as far as 2 AU
This
puts a strong constraints on MHD launch models, and indeed holds the
potential to differentiate between them
Given that the strength of a
rotation argument lies in the survey nature of the findings, we need
to resume this program in order to see if the same rotation signatures
are commonly seen in the NUV, as they are in the optical
Furthermore,
the higher spatial and spectral resolution of STIS in the NUV will
allow us to more accurately quantify the variation in toroidal
velocity as a function of distance from the jet axis
This study will
provide an invaluable statistical argument to support the fact that we
are indeed observing jet rotation
Such a conclusion is critical to
providing observational backing to the widely accepted but untested
theory of magnetocentrifugal ejection
WFC3/UVIS 11657 The Population of Compact Planetary Nebulae in the Galactic Disk We propose to secure narrow- and broad-band images of compact
planetary nebulae (PNe) in the Galactic Disk to study the missing link
of the early phases of post-AGB evolution
Ejected AGB envelopes
become PNe when the gas is ionized
PNe expand, and, when large
enough, can be studied in detail from the ground
In the interim, only
the HST capabilities can resolve their size, morphology, and central
stars
Our proposed observations will be the basis for a systematic
study of the onset of morphology
Dust properties of the proposed
targets will be available through approved Spitzer/IRS spectra, and so
will the abundances of the alpha- elements
We will be able thus to
explore the interconnection of morphology, dust grains, stellar
evolution, and populations
The target selection is suitable to
explore the nebular and stellar properties across the galactic disk,
and to set constraints on the galactic evolutionary models through the
analysis of metallicity and population gradients
STIS/CCD 11634 Probing the Collimation of Pristine Post-AGB Jets with STIS The shaping of planetary and protoplanetary nebulae (PNe and PPNe) is
probably the most exciting yet least understood problem in the late
evolution of ~1-8 solar mass stars
An increasing number of
astronomers believe that fast jet-like winds ejected in the PPN phase
are responsible for carving out the diverse shapes in the dense
envelopes of the Asymptotic Giant Branch (AGB) stars
To date, the
properties of these post-AGB jets have not been characterized and,
indeed, their launching/collimation mechanism is still subject to
controversial debate
This is due to the lack of the direct
observations probing the spatio-kinematic structure of post-AGB winds
in the stellar vicinity (~10e16cm), which is only possible with
HST+STIS
Recently, STIS observations have allowed us for the first time the
DIRECT study of the structure and kinematics of the elusive post-AGB
winds in one PPN, He3-1475 (Sanchez Contreras & Sahai 2001)
Those
winds have been discovered through H-alpha blue-shifted absorption
features in the inner 0
3"-0
7" of the nebula
These STIS observations
have revealed an ultra-fast collimated outflow relatively unaffected
by the interaction with the AGB wind that is totally hidden in
ground-based spectroscopic observations and HST images
The discovery
of the pristine ultra-fast (~2300km/s) jet in He3-1475 is the first
observational confirmation of the presence of collimated outflows as
close as ~10e16cm from the central star
Most importantly, the
spatio-kinematic structure of the ultra-fast jet clearly rules out
hydrodynamical collimation alone and favors magnetic wind collimation
Therefore, STIS observations provide a unique method of probing the
structure, kinematics, and collimation mechanism of the elusive
post-AGB winds
We now propose similar observations for a sample of
bipolar PPNe with ongoing post-AGB ejections in order to investigate
the frequency of jets like those in He3-1475 in other PPNe and
elucidate their nature and collimation mechanism
The observational
characterization of these winds is indispensable for understanding
this violent and important phase of post-AGB evolution
STIS/CCD/MA1/MA2 11616 The Disks, Accretion, and Outflows (DAO) of T Tau Stars Classical T Tauri stars undergo magnetospheric accretion, power
outflows, and possess the physical and chemical conditions in their
disks to give rise to planet formation
Existing high resolution FUV
spectra verify that this spectral region offers unique diagnostics of
these processes, which have the potential to significantly advance our
understanding of the interaction of a star and its accretion disk
To
date the limited results are intriguing, with dramatic differences in
kinematic structure in lines ranging from C IV to H2 among the few
stars that have been observed
We propose to use HST/COS to survey the
disks, outflows, and accretion (the DAO) of 26 CTTS and 6 WTTS in the
FUV at high spectral resolution
A survey of this size is essential to
establish how properties of accretion shocks, winds and disk
irradiation depend on disk accretion rate
Specifically, our goals are
to (1) measure the radiation from and understand the physical
properties of the gas very near the accretion shock as a function of
accretion rate using emission line profiles of hot lines (C IV, Si IV,
N V, and He II); (2) measure the opacity, velocity, and temperature at
the base of the outflow to constrain outflow models using wind
absorption features; and (3) characterize the radiation incident on
disks and protoplanetary atmospheres using H2 line and continuum
emission and reconstructed bright Ly-alpha line emission
STIS/CCD 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
WFC3/UV 11605 Obtaining the Missing Links in the Test of Very Low Mass Evolutionary
Models with HST We are proposing for spatially resolved ACS+HRC observations of 11
very low mass binaries spanning late-M, L and T spectral types in
order to obtain precise effective temperature measurements for each
component
All of our targets are part of a program in which we are
measuring dynamical masses of very low-mass binaries to an
unprecedented precision of 10% (or better)
However, without precise
temperature measurements, the full scientific value of these mass
measurements cannot be realized
Together, mass and temperature
measurements will allow us to distinguish between brown dwarf
evolutionary models that make different assumptions about the interior
and atmospheric structure of these ultra-cool objects
While dynamical
masses can be obtained from the ground in the near-IR, obtaining
precise temperatures require access to optical data which, for these
sub-arcsecond binaries, can only be obtained from space with Hubble
WFC3/UVIS 11594 A WFC3 Grism Survey for Lyman Limit Absorption at z=2 We propose to conduct a spectroscopic survey of Lyman limit absorbers
at redshifts 1
8 < z < 2
5, using WFC3 and the G280 grism
This
proposal intends to complete an approved Cycle 15 SNAP program
(10878), which was cut short due to the ACS failure
We have selected
64 quasars at 2
3 < z < 2
6 from the Sloan Digital Sky Survey
Spectroscopic Quasar Sample, for which no BAL signature is found at
the QSO redshift and no strong metal absorption lines are present at z 2
3 along the lines of sight
The survey has three main
observational goals
First, we will determine the redshift frequency
dn/dz of the LLS over the column density range 16
0 < log(NHI) < 20
3
cm^-2
Second, we will measure the column density frequency
distribution f(N) for the partial Lyman limit systems (PLLS) over the
column density range 16
0 < log(NHI) < 17
5 cm^-2
Third, we will
identify those sightlines which could provide a measurement of the
primordial D/H ratio
By carrying out this survey, we can also help
place meaningful constraints on two key quantities of cosmological
relevance
First, we will estimate the amount of metals in the LLS
using the f(N), and ground based observations of metal line
transitions
Second, by determining f(N) of the PLLS, we can constrain
the amplitude of the ionizing UV background at z~2 to a greater
precision
This survey is ideal for a snapshot observing program,
because the on-object integration times are all well below 30 minutes,
and follow-up observations from the ground require minimal telescope
time due to the QSO sample being bright
STIS/CCD/MA1/MA2 11569 Probing the Atomic and Molecular Inventory of a Beta-Pic Analog, the
Young, Edge-On Debris Disk of HD32297 Edge-on, optically thin, debris disks provide unique opportunities to
probe physical properties of the disk itself
Using the host star as
the background source, trace atomic and molecular disk species can be
detected in absorption
Redfield (2007) found that the recently
discovered edge- on system, HD32297, has the strongest NaI absorption
feature of any known debris disk, 5 times the level observed toward
beta Pic, the canonical edge-on debris disk
Roberge et al
(2006)
compiled the only comprehensive chemical inventory of a debris disk,
using beta Pic, and found that carbon was surprisingly overabundant,
which has important implications for the physical structure and
support of a stable gas disk
What is severely lacking are comparison
observations to determine if such an abundance pattern is typical of
debris disk systems
HD32297 represents the best opportunity to make
such a comparative study and perform a comprehensive gas inventory of
a debris disk, due to its high NaI column density
The UV is critical
for this work due to the large number of strong transitions (almost 50
ions and molecules are accessible) that are located in, and often only
in, the UV
These observations will provide a much needed comparison
dataset for addressing the gas chemistry of debris disk systems that
are at the critical stage, near the end of planet formation, and in
the process of clearing their interplanetary environments
============================================================================== You received this message because you are subscribed to the Google Groups "sci
astro
hubble"
group
To post to this group, visit http://groups
google
com/group/sci
astro
hubble?hl=en To unsubscribe from this group, send email to sci
astro
hubble+unsubscribe@googlegroups
com To change the way you get mail from this group, visit:
http://groups
google
com/group/sci
astro
hubble/subscribe?hl=en To report abuse, send email explaining the problem to abuse@googlegroups
com ==============================================================================
Google Groups: http://groups
google
com/?hl=en The following information is a reminder of your current mailing
list subscription: You are subscribed to the following list:
[list_name] using the following email:
example@example.com You may automatically unsubscribe from this list at any time by
visiting the following URL: https://aus-city
com/cgi-bin/dada/mail
cgi/u/HST_REPORTS/example/example
com/ If the above URL is inoperable, make sure that you have copied the
entire address
Some mail readers will wrap a long URL and thus break
this automatic unsubscribe mechanism
You may also change your subscription by visiting this list's main screen: <[program_url]/list/[list]> If you're still having trouble, please contact the list owner at: The following physical address is associated with this mailing list: [physical_address]=http://groups
google
com/group/sci
astro
hubble/t/5b5677e5d091425a?hl=en
SCHEDULED SUCCESSFUL
<mailto:[list_owner_email]>
This mailing list is announce-only.
HST Status Report list
Private list