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Daily Report #4622
HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science
DAILY REPORT***** # 4622 PERIOD COVERED: 5am May 30 - 5am Jun 02, 2008 (DOY 151/0900z-154/0900z) OBSERVATIONS SCHEDULED NIC1/NIC2/NIC3 8795 NICMOS Post-SAA Calibration - CR Persistence Part 6 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. NIC3 11332 NICMOS Cycle 16 Time Dependent Flat Fields This proposal obtains sequences of NICMOS narrow, medium and broad band filter flat fields for camera 1. In cameras 2 and 3, parallel observations will allow us to obtain high S/N flats for all spectral elements. NIC1/NIC2/NIC3 11330 NICMOS Cycle 16 Extended Dark This takes a series of Darks in parallel to other instruments. WFPC2 11235 HST NICMOS Survey of the Nuclear Regions of Luminous Infrared Galaxies in the Local Universe At luminosities above 10^11.4 L_sun, the space density of far-infrared selected galaxies exceeds that of optically selected galaxies. These `luminous infrared galaxies' {LIRGs} are primarily interacting or merging disk galaxies undergoing enhanced star formation and Active Galactic Nuclei {AGN} activity, possibly triggered as the objects transform into massive S0 and elliptical merger remnants. We propose NICMOS NIC2 imaging of the nuclear regions of a complete sample of 88 L_IR 10^11.4 L_sun luminous infrared galaxies in the IRAS Revised Bright Galaxy Sample {RBGS: i.e., 60 micron flux density 5.24 Jy}. This sample is ideal not only in its completeness and sample size, but also in the proximity and brightness of the galaxies. The superb sensitivity and resolution of NICMOS NIC2 on HST enables a unique opportunity to study the detailed structure of the nuclear regions, where dust obscuration may mask star clusters, AGN and additional nuclei from optical view, with a resolution significantly higher than possible with Spitzer IRAC. This survey thus provides a crucial component to our study of the dynamics and evolution of IR galaxies presently underway with Wide-Field, HST ACS/WFC and Spitzer IRAC observations of these 88 galaxies. Imaging will be done with the F160W filter {H-band} to examine as a function of both luminosity and merger stage {i} the luminosity and distribution of embedded star clusters, {ii} the presence of optically obscured AGN and nuclei, {iii} the correlation between the distribution of 1.6 micron emission and the mid- IR emission as detected by Spitzer IRAC, {iv} the evidence of bars or bridges that may funnel fuel into the nuclear region, and {v} the ages of star clusters for which photometry is available via ACS/WFC observations. The NICMOS data, combined with the HST ACS, Spitzer, and GALEX observations of this sample, will result in the most comprehensive study of merging and interacting galaxies to date. WFPC2 11227 The Orbital Period for an Ultraluminous X-ray Source in NGC1313 The ultraluminous X-ray sources {ULXs} are extragalactic point sources with luminosities that exceed the Eddington luminosity for conventional stellar-mass black holes by factors of 10 - 100. It has been hotly debated whether the ULXs are just common stellar-mass black hole sources with beamed emission or whether they are sub-Eddington sources that are powered by the long-sought intermediate mass black holes {IMBH}. To firmly decide this question, one must obtain dynamical mass measurements through photometric and spectroscopic monitoring of the secondaries of these system. The crucial first step is to establish the orbital period of a ULX, and arguably the best way to achieve this goal is by monitoring its ellipsoidal light curve. The extreme ULX NGC1313 X-2 provides an outstanding target for an orbital period determination because its relatively bright optical counterpart {V = 23.5} showed a 15% variation between two HST observations separated by three months. This level of variability is consistent with that expected for a tidally distorted secondary star. Here we propose a set of 20 imaging observations with HST/WFPC2 to define the orbital period. This would be the first photometric measurement of the orbital period of a ULX binary. Subsequently, we will propose to obtain spectroscopic observations to obtain its radial velocity amplitude and thereby a dynamical estimate of its mass. NIC2 11219 Active Galactic Nuclei in Nearby Galaxies: a New View of the Origin of the Radio-loud Radio-quiet Dichotomy? Using archival HST and Chandra observations of 34 nearby early-type galaxies {drawn from a complete radio selected sample} we have found evidence that the radio-loud/radio-quiet dichotomy is directly connected to the structure of the inner regions of their host galaxies in the following sense: [1] Radio-loud AGN are associated with galaxies with shallow cores in their light profiles [2] Radio-quiet AGN are only hosted by galaxies with steep cusps. Since the brightness profile is determined by the galaxy's evolution, through its merger history, our results suggest that the same process sets the AGN flavour. This provides us with a novel tool to explore the co-evolution of galaxies and supermassive black holes, and it opens a new path to understand the origin of the radio-loud/radio-quiet AGN dichotomy. Currently our analysis is statistically incomplete as the brightness profile is not available for 82 of the 116 targets. Most galaxies were not observed with HST, while in some cases the study is obstructed by the presence of dust features. We here propose to perform an infrared NICMOS snapshot survey of these 82 galaxies. This will enable us to i} test the reality of the dichotomic behaviour in a substantially larger sample; ii} extend the comparison between radio-loud and radio-quiet AGN to a larger range of luminosities. WFPC2 11218 Snapshot Survey for Planetary Nebulae in Globular Clusters of the Local Group 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, 4, 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 more distant than the Magellanic Clouds. These clusters, some of which may be much younger than their counterparts in the Milky Way, 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. FGS 11212 Filling the Period Gap for Massive Binaries The current census of binaries among the massive O-type stars is seriously incomplete for systems in the period range from years to millennia because the radial velocity variations are too small and the angular separations too close for easy detection. Here we propose to discover binaries in this observational gap through a Faint Guidance Sensor SNAP survey of relatively bright targets listed in the Galactic O Star Catalog. Our primary goal is to determine the binary frequency among those in the cluster/association, field, and runaway groups. The results will help us assess the role of binaries in massive star formation and in the processes that lead to the ejection of massive stars from their natal clusters. The program will also lead to the identification of new, close binaries that will be targets of long term spectroscopic and high angular resolution observations to determine their masses and distances. The results will also be important for the interpretation of the spectra of suspected and newly identified binary and multiple systems. FGS 11210 The Architecture of Exoplanetary Systems Are all planetary systems coplanar? Concordance cosmogony makes that prediction. It is, however, a prediction of extrasolar planetary system architecture as yet untested by direct observation for main sequence stars other than the Sun. To provide such a test, we propose to carry out FGS astrometric studies on four stars hosting seven companions. Our understanding of the planet formation process will grow as we match not only system architecture, but formed planet mass and true distance from the primary with host star characteristics for a wide variety of host stars and exoplanet masses. We propose that a series of FGS astrometric observations with demonstrated 1 millisecond of arc per-observation precision can establish the degree of coplanarity and component true masses for four extrasolar systems: HD 202206 {brown dwarf+planet}; HD 128311 {planet+planet}, HD 160691 = mu Arae {planet+planet}, and HD 222404AB = gamma Cephei {planet+star}. In each case the companion is identified as such by assuming that the minimum mass is the actual mass. For the last target, a known stellar binary system, the companion orbit is stable only if coplanar with the AB binary orbit. NIC2 11123 A NICMOS Survey for Proplyds in the RCW 38 Massive Embedded Cluster We propose a search for line emission from photoevaporating protoplanetary disks in the Massive Embedded Cluster RCW 38. These disks would be analogous to the "proplyds" discovered in the Orion Nebula: disks around young low mass stars which are being photoionized by a nearby O star. We will search for these disks in RCW 38 using narrowband imaging in the lines of Paschen alpha and molecular hydrogen (1-0) S(1) with NICMOS. The RCW 38 region is an excellent target for determining whether proplyds are observable in large numbers outside of Orion. It is a young embedded cluster hosting a few hundred low mass young stars with a large percentage showing infrared excess indicating the presence of disks. About 100 of these stars are found within 0.1 pc of the central O5 star, and the cluster is located within a cleared cavity 0.2 pc in size, embedded within a molecular cloud, exposing the cluster members directly to the UV radiation from the O star. Unlike Orion, but like many other young clusters, RCW 38 is not seen in visible light, and infrared imaging is needed. The best line in the infrared for revealing proplyds is the Paschen alpha line, which is not detectable from the ground. Only HST is able to perform these observations. From these observations we will estimate the lifetime of the evaporating disks, and ascertain whether these disks will survive long enough to form planets. NIC3 11120 A Paschen-Alpha Study of Massive Stars and the ISM in the Galactic Center The Galactic center (GC) is a unique site for a detailed study of a multitude of complex astrophysical phenomena, which may be common to nuclear regions of many galaxies. Observable at resolutions unapproachable in other galaxies, the GC provides an unparalleled opportunity to improve our understanding of the interrelationships of massive stars, young stellar clusters, warm and hot ionized gases, molecular clouds, large scale magnetic fields, and black holes. We propose the first large-scale hydrogen Paschen alpha line survey of the GC using NICMOS on the Hubble Space Telescope. This survey will lead to a high resolution and high sensitivity map of the Paschen alpha line emission in addition to a map of foreground extinction, made by comparing Paschen alpha to radio emission. This survey of the inner 75 pc of the Galaxy will provide an unprecedented and complete search for sites of massive star formation. In particular, we will be able to (1) uncover the distribution of young massive stars in this region, (2) locate the surfaces of adjacent molecular clouds, (3) determine important physical parameters of the ionized gas, (4) identify compact and ultra-compact HII regions throughout the GC. When combined with existing Chandra and Spitzer surveys as well as a wealth of other multi-wavelength observations, the results will allow us to address such questions as where and how massive stars form, how stellar clusters are disrupted, how massive stars shape and heat the surrounding medium, and how various phases of this medium are interspersed. WFPC2 11113 Binaries in the Kuiper Belt: Probes of Solar System Formation and Evolution The discovery of binaries in the Kuiper Belt and related small body populations is powering a revolutionary step forward in the study of this remote region. Three quarters of the known binaries in the Kuiper Belt have been discovered with HST, most by our snapshot surveys. The statistics derived from this work are beginning to yield surprising and unexpected results. We have found a strong concentration of binaries among low-inclination Classicals, a possible size cutoff to binaries among the Centaurs, an apparent preference for nearly equal mass binaries, and a strong increase in the number of binaries at small separations. We propose to continue this successful program in Cycle 16; we expect to discover at least 13 new binary systems, targeted to subgroups where these discoveries can have the greatest impact. WFPC2 11025 WFPC2 CYCLE 15 Intflat Linearity Check and Filter Rotation Anomaly Monitor Intflat observations will be taken to provide a linearity check: the linearity test consists of a series of intflats in F555W, in each gain and each shutter. A combination of intflats, visflats, and earthflats will be used to check the repeatability of filter wheel motions. {Intflat sequences tied to decons, visits 1-18 in prop 10363, have been moved to the cycle 15 decon proposal xxxx for easier scheduling.} Note: long-exposure WFPC2 intflats must be scheduled during ACS anneals to prevent stray light from the WFPC2 lamps from contaminating long ACS external exposures. WFPC2 11027 Visible Earth Flats This proposal monitors flatfield stability. This proposal obtains sequences of Earth streak flats to construct high quality flat fields for the WFPC2 filter set. These flat fields will allow mapping of the OTA illumination pattern and will be used in conjunction with previous internal and external flats to generate new pipeline superflats. These Earth flats will complement the Earth flat data obtained during cycles 4-14. NIC2 10603 Multiwavelength Imaging of Edge-on Protoplanetary Disks: Quantifying the Growth of Circumstellar Dust Young, edge-on circumstellar disks are uniquely valuable laboratories for the study of planet formation. In these objects, the central star is occulted from direct view, significant PSF artifacts are absent, and the disk is clearly seen as a central dust lane flanked by faint disk reflected light. The detailed morphology of these nebulae and its variation with wavelength provide crucial information on the disk internal structure and the properties of its constituent dust grains. A key observable is the slope defining the wavelength dependence of the dust scattering opacity, which becomes shallower when grain growth has taken place; multiwavelength resolved disk images are the key dataset enabling such measurements. Recent analyses of three different edge-on disks have revealed a diversity in their dust properties that is indicative of different degrees of dust grain evolution having taken place in each system. This characterization of disk grain growth, when applied comparatively to a larger sample of these objects, would enable the construction of an evolutionary sequence of young disks at successive stages on the road to planet formation. In pursuit of this goal, we have identified a sample of 15 edge-on disks previously discovered by HST or groundbased telescopes, but for which high fidelity, high spatial resolution images do not yet exist in both the optical and near-infrared. We propose broad-band multicolor imaging with NICMOS of all these targets, and ACS imaging of nine of these targets In combination with existing data, the proposed images will form a complete database of high resolution optical/near-IR images for these 15 disk systems. Scattered light modeling will be used to derive the disk structure and dust properties, yielding results that will be of fundamental importance for our understanding of grain properties during protoplanetary disk evolution. NIC2 10487 A Search for Debris Disks in the Coeval Beta Pictoris Moving Group Resolved observations of debris disks present us with the opportunity of studying planetary evolution in other solar systems. We propose to search for debris disks in the Beta Pictoris moving group {8-20 Myrs, 10-50 pc away} , which provides a coeval sample of multiple spectral types, and it has already produced two magnificent resolved debris disks: AU Mic and Beta Pic. Such coeval sample will provide us with a snapshot of the crucial time in disk evolution in which the disk makes the transition from optically thick to optically thin, and it will be useful to study the stellar mass dependence of the disk evolution. FLIGHT OPERATIONS SUMMARY: Significant Spacecraft Anomalies: (The following are preliminary reports of potential non-nominal performance that will be investigated.) HSTARS: 11325 - GSAcq(1,2,1) failed to RGA Hold (Gyro Control) @ 153/19:24:05 COMPLETED OPS REQUEST: (None) COMPLETED OPS NOTES: (None) *********************** SCHEDULED***** SUCCESSFUL FGS GSacq************** 31***************** 30 FGS REacq************** 08***************** 08 OBAD with Maneuver **** 78***************** 78 SIGNIFICANT EVENTS: (None) |
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