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Daily 3844
HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science
DAILY REPORT # 3844 PERIOD COVERED: DOY 111 OBSERVATIONS SCHEDULED ACS/HRC 10330 Coronagraphic search for disks around nearby stars We will use the coronagraphic and imaging modes of the High Resolution camera to study of the role of circumstellar disks in planetary system formation over timescales of ~1-1000 Myr. Our targets comprise pre Main-Sequence {MS} and MS stars, selected by infrared excess, and targets selected from SIRTF surveys. Some targets, like Beta Pictoris have debris disks that have been detected at optical or near-IR wavelengths, while others have disks inferred from mid-IR or ISO observations. We will obtain multicolor images of each target's circumstellar environment for the purpose of {1} detecting and characterizing disk morphologies over all scales {including warps and regions of enhanced or depleted density}, and {2} seeking evidence of embedded planets. Direct and occulted images will be recorded for studying the disks within 2 arcseconds of these targets; the coronagraph will be used to image the outer regions of the disks. Together with existing infrared observations, we will provide constraints on the sizes, distribution, and composition of dust grains. Unconfirmed disks will first be imaged in F606W, and if they exist we may later observe them in F435W and F814W. ACS/HRC 10391 Wavelength and Flux Calibration of the ACS prisms The wavelength calibration of the SBC {PR110L and PR130L} and HRC {PR200L} prisms will be established by observing a planetary nebula in the LMC and QSOs at carefully selected redshifts. Flux calibrations will be derived for each prism by observing white dwarf standards. ACS/HRC/WFC 10263 SAINTS - Supernova 1987A INTensive Survey SAINTS is a program to observe SN 1987A, the brightest supernova in 383 years, as it transforms into supernova remnant {SNR} 1987A, the youngest supernova remnant. HST is the unique and perfect match in scale and in field for spatially-resolved observations of SN 1987A. Rapid changes are taking place in a violent encounter between the fastest-moving debris and the circumstellar ring. This one-time-only event, leading to suddenly appearing hotspots and new emission that can reveal previously hidden gas, is powered by shocks that can be studied simultaneously with HST and with Chandra to great advantage. Both the optical and X-ray flux from the ring are rising rapidly so prompt observations are needed in Cycle 13. Our previous observations reveal a remarkable reverse shock moving upstream through the expanding debris. The reverse shock provides a powerful tool for dissecting the radial structure of the vanished star. The debris from the explosion itself, still excited by radioactivity, is now well resolved by ACS and seen to be aspherical, providing direct clues to the mechanism of the explosion. Many questions about SN 1987A remain unanswered. SAINTS is a comprehensive attempt to use HST to establish the facts of SN 1987A, help to answer interesting questions, and to observe the birth of SNR 1987A. ACS/WFC 10369 ACS internal CTE monitor The charge transfer efficiency {CTE} of the ACS CCD detectors will decline as damage due to on-orbit radiation exposure accumulates. This degradation will be closely monitored at regular intervals, because it is likely to determine the useful lifetime of the CCDs. All the data for this program is acquired using internal targets {lamps} only, so all of the exposures should be taken during Earth occultation time {but not during SAA passages}. This program emulates the ACS pre-flight ground calibration and post-launch SMOV testing {program 8948}, so that results from each epoch can be directly compared. Extended Pixel Edge Response {EPER} and First Pixel Response {FPR} data will be obtained over a range of signal levels for both the Wide Field Channel {WFC}, and the High Resolution Channel {HRC}. ACS/WFC/WFPC2 10129 Resolving Globular Clusters in NGC 1399 We intend to use the ACS/WFC to measure structural parameters {half light radius, King core radius and concentration parameter} of individual globular clusters {GCs} in NGC 1399. Very little is known about structural parameters of globular clusters as a function of radius outside the Local Group. The proposed observations, arranged in a 3x3 ACS mosaic, will allow us to perform the first detailed wide-field study of structural parameters of globular clusters in a giant elliptical galaxy. In particular we will: 1} study the size-galactocentric distance relation of globular clusters out to ~55 kpc {~1.6 eff. radius of the GCS} and determine whether the observed differences in sizes between metal-rich and metal-poor globular cluster in early-type galaxies are primordial and thereby reflect fundamental differences in formation, or are due to projection effects; 2} match the GC position observed with HST/ACS with X-ray binaries identified over the full Chandra field, and use the above sizes to constrain physical models for X-ray binary formation in GCs. 3} The wealth of ground-based data available for this system {photometry+spectroscopy}, will allow us to correlate the structural properties with other GC properties, such as their chemical composition, luminosity, etc. NIC1/NIC2 10410 Anisotropy and obscuration in the near-nuclear regions of powerful radio galaxies Despite the success of the orientation-based unified schemes for powerful radio sources, we are still far from understanding the distribution of obscuring material in the near-nuclear regions of such sources, and how this distribution evolves with radio power. Following on from our highly successful Cycle 7 pilot observations of Cygnus A, we propose a near-IR polarimetric survey of a complete sample of powerful radio galaxies in order map the near-nuclear illumination cones, and investigate the distribution of obscuring material on a 0.1 to 1kpc scale. In particular, the observations will allow us to test the "receding torus model'' which predicts that the opening angles of the illumination cones are smaller in low redshift/low power radio galaxies than in their high redshift/high power counterparts.We will also investigate whether AGN- and jet-driven outflows have a substantial effect on distribution of obscuring material by "hollowing out'' the quasar illumination cones in the more powerful sources. Finally, by using our polarization maps to search for signs of intrinsic anisotropy in the near-IR continuum within the cones, we will investigate the geometry of the near-IR continuum emitting regions close to the quasar nuclei. These observations are not only crucial for our understanding of radio source unification, but also provide key information about the effects of AGN-induced outflows on the ISM of the host galaxies. 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. WFPC2 10363 WFPC2 CYCLE 13 Intflat and Visflat Sweeps and Filter Rotation Anomaly Monitor Using intflat observations, this WFPC2 proposal is designed to monitor the pixel-to-pixel flatfield response and provide a linearity check. The intflat sequences, to be done once during the year, are similar to those from the Cycle 12 program 10075. The images will provide a backup database as well as allow monitoring of the gain ratios. The sweep is a complete set of internal flats, cycling through both shutter blades and both gains. The linearity test consists of a series of intflats in F555W, in each gain and each shutter. As in Cycle 12, we plan to continue to take extra visflat, intflat, and earthflat exposures to test the repeatability of filter wheel motions. FLIGHT OPERATIONS SUMMARY: Significant Spacecraft Anomalies: (The following are preliminary reports of potential non-nominal performance that will be investigated.) HSTAR 9784: ACS TA Failed due to Guide Star Acg failure @ 111/1724z. ACS TA (target acquisition) scheduled at 111/17:23:16 (HD-100623) failed due to REACQ failure (HSTAR#9785).Observations affected: ACS 139-142; Proposal 10330, titled Coronagraphic search for disks around nearby stars. Under investigation. HSTAR 9785: REACQ(2,1,2) fails to RGA control, scan step limit exceeded on FGS 2. REACQ(2,1,2) at 111/17:17:32 ended in gyro control due to 4 occurrences of scan step limit exceeded on FGS 2 beginning at 17:19:41. Initial GSACQ(2,1,2) at 15:42:17 was successful with no scan step limits exceeded. ACS target acquisition failed due to this REACQ failure (HSTAR 9784). Under investigation. Observations affected: ACS 139 to 142. COMPLETED OPS REQs: None OPS NOTES EXECUTED: 1331-0 Change JERRCNT Limit @111/2130z SCHEDULED SUCCESSFUL FAILURE TIMES FGS Gsacq 07 07 FGS Reacq 12 11 111/1720z(HSTAR#9785) FHST Update 08 08 LOSS of LOCK SIGNIFICANT EVENTS: None |
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