NASA Hubble Space Telescope Daily Report #4128
HUBBLE SPACE TELESCOPE – Continuing to collect World Class Science
DAILY REPORT # 4128
PERIOD COVERED: UT June 05, 2006 (DOY 156)
OBSERVATIONS SCHEDULED
ACS/HRC 10335
Black Holes in Globular Clusters
Search for >3000 solar mass black holes at the centers of three Galactic globular clusters using stellar proper motions.
ACS/HRC 10556
Neutral Gas at Redshift z=0.5
Damped Lyman-alpha systems {DLAs} are used to track the bulk of the neutral hydrogen gas in the Universe. Prior to HST UV spectroscopy, they could only be studied from the ground at redshifts z>1.65. However, HST has now permitted us to discover 41 DLAs at z<1.65 in our previous surveys. Followup studies of these systems are providing a wealth of information about the evolution of the neutral gas phase component of the Universe. But one problem is that these 41 low-redshift systems are spread over a wide range of redshifts spanning nearly 70% of the age of the Universe. Consequently, past surveys for low-redshift DLAs have not been able to offer very good precision in any small redshift regime. Here we propose an ACS-HRC- PR200L spectroscopic survey in the redshift interval z=[0.37, 0.7] which we estimate will permit us to discover another 41 DLAs. This will not only allow us to double the number of low-redshift DLAs, but it will also provide a relatively high-precision regime in the low-redshift Universe that can be used to anchor evolutionary studies. Fortunately DLAs have high absorption equivalent width, so ACS-HRC-PR200L has high-enough resoultion to perform this proposed MgII-selected DLA survey.
ACS/HRC/WFC 10758
ACS CCDs daily monitor
This program consists of a set of basic tests to monitor, the read noise, the development of hot pixels and test for any source of noise in ACS CCD detectors. The files, biases and dark will be used to create reference files for science calibration. This programme will be for the entire lifetime of ACS. Changes from cycle 13:- The default gain for WFC is 2 e-/DN. As before bias frames will be collected for both gain 1 and gain 2. Dark frames are acquired using the default gain {2}. This program cover the period May, 31 2006- Oct, 1-2006. The first half of the program has a different proposal number: 10729.
ACS/WFC 10496
Decelerating and Dustfree: Efficient Dark Energy Studies with Supernovae and Clusters
We propose a novel HST approach to obtain a dramatically more useful “dust free” Type Ia supernovae {SNe Ia} dataset than available with the previous GOODS searches. Moreover, this approach provides a strikingly more efficient search-and-follow-up that is primarily pre- scheduled. The resulting dark energy measurements do not share the major systematic uncertainty at these redshifts, that of the extinction correction with a prior. By targeting massive galaxy clusters at z > 1 we obtain a five-times higher efficiency in detection of Type Ia supernovae in ellipticals, providing a well-understood host galaxy environment. These same deep cluster images then also yield fundamental calibrations required for future weak lensing and Sunyaev-Zel’dovich measurements of dark energy, as well as an entire program of cluster studies. The data will make possible a factor of two improvement on supernova constraints on dark energy time variation, and much larger improvement in systematic uncertainty. They will provide both a cluster dataset and a SN Ia dataset that will be a longstanding scientific resource.
ACS/WFC 10551
Gamma-Ray Bursts from Start to Finish: A Legacy Approach
The progenitors of long-duration GRBs are now known to be massive stars. This result lends credence to the collapsar model, where a rotating massive star ends its life leaving a black hole or a highly magnetized neutron star, and confirms its essential aspects. The focus of attention now is on the black hole or magnetar engines that power the bursts. Somehow these engines create the most highly relativistic and highly collimated outflows that we know of, through mechanisms that no current theory can explain. These astrophysical laboratories challenge our understanding of relativistic shocks, of mechanisms for extracting energy from a black hole, and of how physics works in extreme conditions. The launch of Swift is bringing us into a new era, where we can make broadband observations that will enable us to study these fascinating physical processes. We propose here an ambitious, comprehensive program to obtain the datasets that will become the standard that any successful model for the central engine must explain. This programs leverages the HST observations to the maximum extent by our commitment of Swift observations, a Large program at the VLA, and extensive ground-based optical resources. By studying the engines and searching for jets in a variety of events, this program will investigate the conditions necessary for the engine and jet formation itself.
ACS/WFC 10573
Globular Clusters in the Direction of the Inner Galaxy
The age, chemical and kinematic distributions of stellar populations provide powerful constraints on models of the formation and evolution of the Milky Way. The globular clusters constitute an especially useful case because the stars within individual clusters are coeval and spatially distinct. But a serious limitation in the study of many globular clusters — especially those located near the Galactic Center — has been the existence of large absolute and differential extinction by foreground dust. We propose to use the ACS to map the differential extinction and remove their effects in a large sample of globular clusters located in the direction of the inner Galaxy using a technique refined recently by von Braun and Mateo {2001}. These observations and their analyses will let us produce high quality color-magnitude diagrams of these poorly studied clusters that will allow us to determine these clusters’ relative ages, distances and chemistry and to address important questions about the formation and the evolution of the inner Galaxy. Our aim for these ACS observations is to obtain data for the most crowded clusters in the inner Galaxy where the excellent spatial resolution of the ACS is most necessary.
ACS/WFC 10626
A Snapshot Survey of Brightest Cluster Galaxies and Strong Lensing to z = 0.9
We propose an ACS/WFC snapshot survey of the cores of 150 rich galaxy clusters at 0.3 < z < 0.9 from the Red Sequence Cluster Survey {RCS}. An examination of the galaxian light in the brightest cluster galaxies, coupled with a statistical analysis of the strong-lensing properties of the sample, will allow us to contrain the evolution of both the baryonic and dark mass in cluster cores, over an unprecedented redshift range and sample size. In detail, we will use the high- resolution ACS images to measure the metric {10 kpc/h} luminosity and morphological disturbances around the brightest clusters galaxies, in order to calibrate their accretion history in comparison to recent detailed simulations of structure formation in cluster cores. These images will also yield a well-defined sample of arcs formed by strong lensing by these clusters; the frequency and detailed distribution {size, multiplicity, redshifts} of these strong lens systems sets strong constraints on the total mass content {and its structure} in the centers of the clusters. These data will also be invaluable in the study of the morphological evolution and properties of cluster galaxies over a significant redshift range. These analyses will be supported by extensive ongoing optical and near-infrared imaging, and optical spectroscopy at Magellan, VLT and Gemini telescopes, as well as host of smaller facilities.
NIC1/NIC2/NIC3 8793
NICMOS Post-SAA calibration – CR Persistence Part 4
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 images. Each observation will need its own CRMAP, as different SAA passages leave different imprints on the NICMOS detectors.
S/C/NIC1 10724
NICMOS Focus Monitoring
The purpose of this proposal is to determine the best focus for all three NICMOS detectors. The program will be executed every ~6 weeks. Each execution will concern a single detector, except two occasions which will include NIC3. In total NIC1 and NIC2 will be monitored 4 times each during the current cycle, while NIC3 will only be monitored twice. The program starts with a focus sweep using only the NIC1 camera {visit 11}. The following observation is with the NIC2 camera {visit 12} after about 45 days. This pattern is repeated throughout the period except for Jan 1-8 and Jul 1-8 where also the NIC3 camera is used. In total this will result in 10 orbits. Notice that VISIT #1 #2 refers to visits for #1 sequential visit number for a given camera #2 camera in question visit 32 is therefore the third visit for camera 2. Some tweaking of dates and sources are necessary to ensure visibility under 2-gyro mode. These are the dates and targets for Cycel14: Visit 11: Oct 01-08 NIC1 NGC1850 Visit 12: Nov 15-22 NIC2 NGC3603 Visit 21: Jan 01-15 NIC1 NGC3603 Visit 13: Jan 01-15 NIC3 NGC3603 Visit 22: Feb 15-22 NIC2 NGC3603 Visit 31: Apr 01-15 NIC1 NGC1850 Visit 32: May 22-31 NIC2 NGC3603 Visit 41: Jun 15-22 NIC1 NGC1850 Visit 23: Jun 15-22 NIC3 NGC1850 Visit 42: Aug 07-22 NIC2 NGC3603
WFPC2 10748
WFPC2 CYCLE 14 Standard Darks
This dark calibration program obtains dark frames every week in order to provide data for the ongoing calibration of the CCD dark current rate, and to monitor and characterize the evolution of hot pixels. Over an extended period these data will also provide a monitor of radiation damage to the CCDs.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are preliminary reports of potential non-nominal performance that will be investigated.)
HSTARS:
10297 – Battery 3 Temp Limit Battery 3 Temp(CBAT3TMP) toggled Yellow high = 5.668 degC for several minutes. Battery temperature limits are currently set for High Sun Time, high yellow limit is 5.5 degC. Anomalous temperature occurred while the s/c was in orbit day.
10298 – GSACQ(2,3,2) fails, Search Radius Limit on FGS 2 @ 157/07:10:12z GSACQ(2,3,2) at 157/07:03:53 failed due to search radius limit exceeded on FGS 2 at 07:10:12.
1805 ESB message was received at 07:03:01 in the early stage of the GSACQ. ESB message A0A (“FGS Fine Lock failed – Timed out waiting for fine lock”) was received at 07:10:26.
OBAD at 06:54:26 prior to GSACQ had total RSS error of 7.81 arcseconds.
COMPLETED OPS REQUEST:
17770-0 – Batt 5 Rec Conting: Lower VTFE Curves to K1L4-150mV @ 156/1817z
17695-2 – Monitor VehConLaw.Integral Path Data via TMDIAG Slot 0 (Generic OR) @ 156/2028z
SCHEDULED SUCCESSFUL FAILURE TIMES
FGS GSacq 09 08 (HSTAR #
10298)
FGS REacq 06 06
OBAD with Maneuver 30 30
COMPLETED OPS NOTES:
1454-4 – Update DMS Limits (DS1T2, KEYMNDMS) @ 156/1745z, 156/1944z
SIGNIFICANT EVENTS:
FLASH REPORT
VTFE Curve Adjustment – (Mon, 5 Jun, EPS SE DLewis) – On DOY 2006/156 at 10:11 GMT, battery 3 exceeded the ground limit of 5.5 DegC at 5.67 DegC. The temperatures continued to exceed its ground limit each orbit reaching a high value of 6.34 DegC. Since we are still declining from the recent high sun-time, as per the high sun-time contingency, EPS SEs lowered the VTFE curves on all the batteries by an additional 50mV to K1L4-150mV. The commanding was executed via Ops Request 17770-0 on DOY 2006/156 at 18:17 GMT. The system was monitored for 1 full orbit in the SMOR, and EPS SE observed that the battery 3 temperature decreased by ~0.67 DegC (2 counts) from the anomalous value of 6.34 DegC. EPS SEs will continue to remotely monitor the system.
