A Space & astronomy forum. SpaceBanter.com

Go Back   Home » SpaceBanter.com forum » Astronomy and Astrophysics » Hubble
Site Map Home Authors List Search Today's Posts Mark Forums Read Web Partners

Daily Rpt #4942



 
 
Thread Tools Display Modes
  #1  
Old October 1st 09, 07:41 PM posted to sci.astro.hubble
Bassford, Lynn[_2_]
external usenet poster
 
Posts: 91
Default Daily Rpt #4942

HUBBLE SPACE TELESCOPE - Continuing to Collect World Class Science

DAILY REPORT #4942

PERIOD COVERED: 5am September 30 - 5am October 1, 2009 (DOY 273/09:00Z-274/09:00Z)

OBSERVATIONS SCHEDULED

ACS/WFC3 11879

CCD Daily Monitor (Part 1)

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 352 orbits (22 weeks) from 31 August
2009 to 31 January 2010.

NIC1/NIC2/NIC3 11947

Extended Dark Monitoring

This program takes a series of darks to obtain darks (including
amplifier glow, dark current, and shading profiles) for all three
cameras in the read-out sequences used in Cycle 17. A set of 12 orbits
will be observed every two months for a total of 72 orbits for a 12
month Cycle 17. This is a continuation of Cycle 16 program 11330
scaled down by ~80%.

The first orbit (Visit A0) should be scheduled in the NICMOS SMOV
after the DC Transfer Test (11406) and at least 36h before the Filter
Wheel Test (11407). Data download using fast track.

The following 28 orbits (visit A1-N2) should be scheduled AFTER the
SMOV Proposal 11407 (Filter Wheel Test). This is done in order to
monitor the dark current following an adjustment of the NCS set-point.
These visits should be executed until the final temperature is reached
during SMOV.

NIC1/NIC2/NIC3 8795

NICMOS Post-SAA Calibration - CR Persistence Part 6

This is 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
'Use After' 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.

STIS/CCD 11606

Dynamical Hypermassive Black Hole Masses

We will use STIS spectra to derive the masses of 5 hypermassive black
holes (HMBHs). From the observed scaling relations defined by less
massive spheroids, these objects are expected to reside at the nuclei
of host galaxies with stellar velocity dispersions greater than 320
km/s. These 5 targets have confirmed regular gas distributions on the
scales of the black hole sphere of influence. It is essential that the
sphere of influence is resolved for accurate determinations of black
hole mass (0.1"). These scales cannot be effectively observed from the
ground. Only two HMBHs have had their masses modeled so far; it is
impossible to draw any general conclusions about the connections
between HMBH mass and their massive host galaxies. With these 5
targets we will determine whether these HMBHs deviate from the scaling
relations defined by less massive spheroids. A larger sample will
allow us to firmly anchor the high mass end of the correlation between
black hole mass and stellar velocity dispersion, and other scaling
relations. Therefore we are also conducting a SNAPshot program with
which we expect to detect a further 24 HMBH candidates for STIS
observation in future cycles. At the completion of this project we
will have populated the high mass end of the scaling relations with
the sample sizes enjoyed by less massive spheroids.

STIS/CCD 11844

CCD Dark Monitor Part 1

The purpose of this proposal is to monitor the darks for the STIS CCD.

STIS/CCD 11846

CCD Bias Monitor-Part 1

The purpose of this proposal is to 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/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/ACS/IR 11359

Panchromatic WFC3 Survey of Galaxies at Intermediate z: Early Release
Science Program for Wide Field Camera 3

The unique panchromatic capabilities of WFC3 will be used to survey
the structure and evolution of galaxies at the peak of the galaxy
assembly epoch. Deep ultraviolet and near-IR imaging and slitless
spectroscopy of existing deep multi-color ACS fields will be used to
gauge star-formation and the growth of stellar mass as a function of
morphology, structure and surrounding density in the critical epoch 1
z 4. Images in the F225W, F275W, and F336W filters will identify
galaxies at z 1.5 from their UV continuum breaks, and provide
star-formation indicators tied directly to both local and z 3
populations. Deep near-IR (F125W and F160W) images will probe the
stellar mass function well below 10^9 Msun for mass-complete samples.
Lastly, the WFC3 slitless UV and near-IR grisms will be used to
measure redshifts and star-formation rates from H- alpha and
rest-frame UV continuum slope. This WFC3 ERS program will survey one 4
x 2 mosaic for a total area of 50 square arcminutes to 5-sigma depths
of m_AB = 27 in most filters from the mid-UV through the near-IR.

This multicolor high spatial resolution data set will allow the user
to gauge the growth of galaxies through star-formation and merging.
High precision photometric and low- resolution spectroscopic redshifts
will allow accurate determinations of the faint-end of the luminosity
and mass functions, and will shed light on merging and tidal
disruption of stellar and gaseous disks. The WFC3 images will also
allow detailed studies of the internal structure of galaxies, and the
distribution of young and old stellar populations. This program will
demonstrate the unique power of WFC3 by applying its many diverse
modes and full panchromatic capability to a forefront problem in
astrophysics.

WFC3/ACS/IR 11584

Resolving the Smallest Galaxies with ACS

An order of magnitude more dwarf galaxies are expected to inhabit the
Local Group, based on currently accepted galaxy formation models, than
have been observed. This discrepancy has been noted in environments
ranging from the field to rich clusters, with evidence emerging that
lower density regions contain fewer dwarfs per giant than higher
density regions, in further contrast to model predictions. However,
there is no complete census of the faintest dwarf galaxies in any
environment. The discovery of the smallest and faintest dwarfs is
hampered by the limitations in detecting such compact or low surface
brightness galaxies, and this is compounded by the great difficulty in
determining accurate distances to, or ascertaining group membership
for, such faint objects. The M81 group provides a powerful means for
establishing membership for faint galaxies in a low density region.
With a distance modulus of 27.8, the tip of the red giant branch
(TRGB) appears at I ~ 24, just within the reach of ground based
surveys. We have completed a 65 square degree survey in the region
around M81 with the CFHT/MegaCam. Half of our survey was completed
before Cycle 16 and we were awarded time with WFPC2 to observe 15 new
candidate dwarf galaxy group members in F606W and F814W bands in order
to construct color-magnitude diagrams from which to measure accurate
TRGB distances and determine star formation and metallicity histories.
The data obtained show that 8 - 9 of these objects are galaxies at the
same distance as M81. In completing our survey, we have discovered an
additional 8 candidate galaxies we propose to image with ACS in order
to measure TRGB distances and establish membership. We also wish to
re-observe our smallest candidate group member and a tidal dwarf
candidate with deeper observations made possible with ACS. Once
membership has been established for this second set of candidates, we
will have a complete census of the dwarf galaxy population in the M8
group to M_r ~ -10, allowing us to obtain a firm measurement of the
luminosity function faint-end slope, and, combined with previous HST
data, to provide a complete inventory of the age and abundance
properties for the collapsed core of the M81 group.

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 11629

Far-UV Phase-Resolved Spectroscopy of PSR B0656+14

X-ray observations of the brightest middle-aged pulsar PSR B0656+14
have shown a Wien tail of thermal emission from the neutron star
surface in soft X-rays and magnetospheric emission at higher X-ray
energies. Optical/near-UV observations of this pulsar have shown that
its emission is predominantly magnetospheric in this range and
indicated that the Rayleigh-Jeans thermal component could dominate in
the far-UV. This hypothesis has been confirmed by our STIS/FUV
observation, which, however, was too short to separate and study the
thermal emission (only 2 of 8 allocated orbits were executed before
the STIS failure). Using the superior sensitivity of COS/FUV, we will
perform phase-resolved spectroscopy and wavelength-resolved timing of
the pulsar radiation in the 1105-1900 A band. The results of this
observation, combined with the optical-UV and X-ray data, will allow
us to firmly separate the thermal and magnetospheric components and
infer the temperature and radius of the neutron star, which is
important for understanding the thermal evolution of neutron stars and
constraining the composition and equation of state of their superdense
interiors.

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/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 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/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.

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 9 9
FGS REAcq 7 7
OBAD with Maneuver 8 8

SIGNIFICANT EVENTS: (None)

 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Daily #4084 Joe Cooper Hubble 0 April 4th 06 02:44 PM
Daily #4070 Joe Cooper Hubble 0 March 28th 06 05:27 PM
Daily #4069 Joe Cooper Hubble 0 March 28th 06 05:22 PM
Daily #4068 Joe Cooper Hubble 0 March 13th 06 03:26 PM
Daily #4067 Joe Cooper Hubble 0 March 10th 06 02:39 PM


All times are GMT +1. The time now is 12:54 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 SpaceBanter.com.
The comments are property of their posters.