#1
|
|||
|
|||
Daily Report #4756
HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science
DAILY REPORT****** #4756 PERIOD COVERED: 5am December 12 - 5am December 15, 2008 (DOY *************************** 347/1000z-350/1000z) OBSERVATIONS SCHEDULED WFPC2 11962 A New Supernova in the Antennae; Narrowing in on the Hubble Constant and Dark Energy A measurement of the Hubble constant to a precision of a few percent would be a powerful aid to the investigation of the nature of dark energy and a potent "end-to-end" test of the present cosmological model. In Cycle 15 we constructed a new, streamlined distance ladder utilizing high-quality type Ia supernova data and observations of Cepheids with HST in the near-IR to minimize the dominant sources of systematic uncertainty in past measurements of the Hubble constant and reduce its total uncertainty to a little under 5%. Here we propose to exploit this new route with a rare opportunity to begin reducing the remaining uncertainty. SN 2007sr in the Antennae (NGC 4038/9) is the rare SN Ia which is suitable for increasing the precision of small calibration sample of SNe Ia. Even rarer is that it is close enough that it's Cepheids are within range of observing with WFPC2 (and NICMOS, should it return to life). But we need to act fast as the window of long visibility and fixed orient runs from mid-early December 2008 to early March 2009. We request 34 orbits with WFPC2 to find the Cepheids in the SN host. We also request 16 orbits to observe the Cepheids we find with Camera 2, F160W if NICMOS becomes available by April 2009 . (If NICMOS does not return we would forgo these observations and ask the TTRB to let us make them with our own WFC3-IR allocation, though we much prefer the smaller pixel size of NIC2). FGS 11943 Binaries at the Extremes of the H-R Diagram We propose to use HST/Fine Guidance Sensor 1r to survey for binaries among some of the most massive, least massive, and oldest stars in our part of the Galaxy. FGS allows us to spatially resolve binary systems that are too faint for ground-based, speckle or optical long baseline interferometry, and too close to resolve with AO. We propose a SNAP-style program of single orbit FGS TRANS mode observations of very massive stars in the cluster NGC 3603, luminous blue variables, nearby low mass main sequence stars, cool subdwarf stars, and white dwarfs. These observations will help us to (1) identify systems suitable for followup studies for mass determination, (2) study the role of binaries in stellar birth and in advanced evolutionary states, (3) explore the fundamental properties of stars near the main sequence-brown dwarf boundary, (4) understand the role of binaries for X-ray bright systems, (5) find binaries among ancient and nearby subdwarf stars, and (6) help calibrate the white dwarf mass - radius relation. FGS 11942 Increasing the Accuracy of HST Astrometry with FGS1R We propose to observe six exoplanetary system host stars and two planetary nebulae central stars with FGS1r. All objects have been previously observed under proposals GO-09233, -09969, -10989, and -11210. These observations will significantly extend the time baseline, permitting improvements in the determination of proper motion. This systematic motion must be removed to get at the perturbation of interest, either due to exoplanetary companions or the orbital motion of the Earth (parallax). In most cases the perturbation orbits will also improve. We improve either companion mass or PN parallax. For one target, GJ 876, theoretical dynamical modelers have proposed an inclination closer to 50 degrees, while FGS3 measurements indicated an inclination closer to 84 degrees. These new data, once combined with our older FGS3 data, will permit an independent remeasurement of the inclination of the outermost companion, and a re-evaluation of widely used dynamical algorithms. FGS 11870 Calibrating FGS1R's Optical Field Angle Distortion (OFAD), Second Epoch This proposal gathers the data needed to calibrate the optical field angle distortions in FGS1r to the level of accuracy required for astrometry science. Selected stars from the galactic cluster M35 are repeatedly observed in POSITION mode by FGS1r with F583W filter at a variety of spacecraft pointings and telescope roll angles. Ideally the observations are to occur at a time when this ecliptic star field is near the anti-sun direction so that HST's roll angle is unconstrained. Unfortunately this is not possible under two gyro operations. Therefore, the observations in this proposal are somewhat very constrained in roll. However, this test should suffice as an adequate update to the original FGS1r OFAD that executed in December 2000. For each visit, the desired telescope pointing is specified by POS TARG and ORIENT special requirements. 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. FGS 11213 Distances to Eclipsing M Dwarf Binaries We propose HST FGS observations to measure accurate distances of 5 nearby M dwarf eclipsing binary systems, from which model-independent luminosities can be calculated. These objects have either poor or no existing parallax measurements. FGS parallax determinations for these systems, with their existing dynamic masses determined to better than 0.5%, would serve as model-independent anchor points for the low-mass end of the mass-luminosity diagram. 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 11103 A Snapshot Survey of The Most Massive Clusters of Galaxies We propose the continuation of our highly successful SNAPshot survey of a sample of 125 very X-ray luminous clusters in the redshift range 0.3-0.7. As demonstrated by the 25 snapshots obtained so far in Cycle14 and Cycle15 these systems frequently exhibit strong gravitational lensing as well as spectacular examples of violent galaxy interactions. The proposed observations will provide important constraints on the cluster mass distributions, the physical nature of galaxy-galaxy and galaxy-gas interactions in cluster cores, and a set of optically bright, lensed galaxies for further 8-10m spectroscopy. All of our primary science goals require only the detection and characterization of high-surface-brightness features and are thus achievable even at the reduced sensitivity of WFPC2. Because of their high redshift and thus compact angular scale our target clusters are less adversely affected by the smaller field of view of WFPC2 than more nearby systems. Acknowledging the broad community interest in this sample we waive our data rights for these observations. Due to a clerical error at STScI our approved Cycle15 SNAP program was barred from execution for 3 months and only 6 observations have been performed to date - reinstating this SNAP at Cycle16 priority is of paramount importance to reach meaningful statistics. FLIGHT OPERATIONS SUMMARY: Significant Spacecraft Anomalies: (The following are preliminary reports of potential non-nominal performance that will be investigated.) HSTARS: 11604 - GSAcq(2,3,2) failed due to QF2STOPF flag on FGS-2 At 347/08:40:36 GSAcq (2,3,2) scheduled from 08:36:52 - 08:44:10 failed due to QF2STOPF flag on FGS-2. Observation affected: Astrometry Proposal ID 11943 11605 - GSACQ(2,3,2) failed, Search Radius Limit exceeded on FGS 2 GSACQ(2,3,2) at 347/13:21:26 failed to RGA control with Search Radius Limit exceeded on FGS 2 at 13:28:01. Observations affected: Astrometry, proposal ID 11943. 11607 - GSAcq(2,3,3) failed to RGA Hold (Gyro Control) Upon acquisition of signal at 349/13:45:16, the GSAcq(2,3,3) scheduled at 349/13:19:23 - 13:27:28 had failed to RGA Hold due to (QF2STOPF) stop indication flag set on FGS-2. Observation affected: Astrometry, Proposal ID 11942. 11608 - GSAcq(2,3,3) failed to RGA Hold (Gyro Control) Upon acquisition of signal at 349/15:22:15, the GSAcq(2,3,3) scheduled at 349/14:55:16 - 15:03:21 had failed to RGA Hold due to (QF2STOPF) stop indication flag set on FGS-2. Observations affected: Astrometry, Proposal ID 11942. 11609 - GSAcq(2,3,3) failed to RGA Hold (Gyro Control) GSAcq(2,3,3) scheduled at 349/18:07:02 - 18:15:07 failed to RGA Hold due to (QF2STOPF) stop flag indication on FGS-2. Observations affected: Astrometry, Proposal ID 11942. 11610 - GSAcq(2,3,3) failed to RGA Hold (Gyro Control) GSAcq(2,3,3) scheduled at 349/19:42:55 - 19:51:00 failed to RGA Hold due to (QF2STOPF) stop flag indication on FGS-2. Observations affected: Astrometry, Proposal ID 11942. 11611 - GSAcq(2,3,3) failed to RGA Hold (Gyro Control) GSAcq(2,3,3) scheduled at 349/21:18:49 - 21:26:54 failed to RGA Hold due to (QF2STOPF) stop flag indication on FGS-2. Observations affected: Astrometry, Proposal ID 11942. COMPLETED OPS REQUEST: (None) COMPLETED OPS NOTES: (None) ********************** SCHEDULED***** SUCCESSFUL FGS GSacq************** 29**************** 22 FGS REacq************** 06**************** 06 OBAD with Maneuver **** 70**************** 68 SIGNIFICANT EVENTS: (None) |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
DAILY REPORT #3903 | Lynn Bassford | Hubble | 0 | July 20th 05 09:48 PM |
DAILY REPORT #3901 | Lynn Bassford | Hubble | 0 | July 20th 05 09:47 PM |
DAILY REPORT #3899 | Lynn Bassford | Hubble | 0 | July 20th 05 09:47 PM |
Daily Report | [email protected] | Hubble | 0 | October 29th 04 04:59 PM |
HST Daily Report 131 | George Barbehenn | Hubble | 0 | May 11th 04 02:48 PM |