363 research outputs found

    The Montage Image Mosaic Service: Custom Image Mosaics On-Demand

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    The Montage software suite has proven extremely useful as a general engine for reprojecting, background matching, and mosaicking astronomical image data from a wide variety of sources. The processing algorithms support all common World Coordinate System (WCS) projections and have been shown to be both astrometrically accurate and flux conserving. The background ‘matching’ algorithm does not remove background flux but rather finds the best compromise background based on all the input and matches the individual images to that. The Infrared Science Archive (IRSA), part of the Infrared Processing and Analysis Center (IPAC) at Caltech, has now wrapped the Montage software as a CGI service and provided a compute and request management infrastructure capable of producing approximately 2 TBytes / day of image mosaic output (e.g. from 2MASS and SDSS data). Besides the basic Montage engine, this service makes use of a 16-node LINUX cluster (dual processor, dual core) and the ROME request management software developed by the National Virtual Observatory (NVO). ROME uses EJB/database technology to manage user requests, queue processing and load balance between users, and managing job monitoring and user notification. The Montage service will be extended to process userdefined data collections, including private data uploads

    Occupancy and abundance of a West African mangabey species (\u3ci\u3eCercocebus atys\u3c/i\u3e Audebert, 1797) in forest patch habitat

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    Sooty mangabeys are Old World primates from the Upper Guinea Rainforests of West Africa. They suffer from habitat degradation due to deforestation and hunting for the bush-meat trade. Tiwai Island and adjacent small islands are a small protected area surrounded by the Moa River that is known for its high diversity of primate species. We evaluated the occupancy and abundance of sooty mangabeys on Tiwai Island and the surrounding islands using camera traps during 2008–2011. Over two seasons, we obtained a naïve occupancy rate of 0.77 for Tiwai Island but only 0.19 for surrounding smaller islands. We used Abundance-Induced Heterogeneity Model and Royle Repeated Count Model to estimate the abundance of 326 ± 92 (SE) and 530 ± 102 (SE) individuals of sooty mangabeys respectively. Based on these occurrences, sooty mangabeys usually appeared in riparian, mature and young secondary forests. Activity patterns of sooty mangabeys based on circadian patterns of detections confirmed that they were diurnal with several activity peaks during the daylight hours. The results of this study suggest that a viable population of sooty mangabeys still inhabits Tiwai Island and its vicinity, but that their core population is primarily limited to the Tiwai Island reserve. Thus, there is a need to protect the island and its adjacent habitats to ensure the conservation of sooty mangabeys in particular and other primate species in general

    The NStED Exoplanet Transit Survey Service

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    The NASA Star and Exoplanet Database (NStED) is a general purpose stellar archive with the aim of providing support for NASA's planet finding and characterization goals, stellar astrophysics, and the planning of NASA and other space missions. There are two principal components of NStED: a database of (currently) 140,000 nearby stars and exoplanet-hosting stars, and an archive dedicated to high-precision photometric surveys for transiting exoplanets. We present a summary of the latter component: the NStED Exoplanet Transit Survey Service (NStED-ETSS), along with its content, functionality, tools, and user interface. NStED-ETSS currently serves data from the TrES Survey of the Kepler Field as well as dedicated photometric surveys of four stellar clusters. NStED-ETSS aims to serve both the surveys and the broader astronomical community by archiving these data and making them available in a homogeneous format. Examples of usability of ETSS include investigation of any time-variable phenomena in data sets not studied by the original survey team, application of different techniques or algorithms for planet transit detections, combination of data from different surveys for given objects, statistical studies, etc. NStED-ETSS can be accessed at \tt{http://nsted.ipac.caltech.edu}Comment: To appear in the Proceedings of the 253rd IAU Symposium: "Transiting Planets", May 2008, Cambridge, MA. 4 pages, 2 figure

    Thermodynamics of clay – Drug complex dispersions: Isothermal titration calorimetry and high-performance liquid chromatography

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    An understanding of the thermodynamics of the complexation process utilized in sustaining drug release in clay matrices is of great importance. Several characterisation techniques as well as isothermal calorimetry were utilized in investigating the adsorption process of a model cationic drug (diltiazem hydrochloride, DIL) onto a pharmaceutical clay system (magnesium aluminium silicate, MAS). X-ray powder diffraction (XRPD), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and optical microscopy confirmed the successful formation of the DIL-MAS complexes. Drug quantification from the complexes demonstrated variable behaviour in the differing media used with DIL degrading to desacetyl diltiazem hydrochloride (DC-DIL) in the 2 M HCl media. Here also, the authors report for the first time two binding processes that occurred for DIL and MAS. A competitor binding model was thus proposed and the thermodynamics obtained suggested their binding processes to be enthalpy driven and entropically unfavourable. This information is of great importance for a formulator as care and consideration should be given with appropriate media selection as well as the nature of binding in complexes

    Unconventional PDV applications: detecting plasma and radiation

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    Author Institution: Sandia National LaboratoriesSlides presented at the 2018 Photonic Doppler Velocimetry (PDV) Users Workshop, Drury Plaza Hotel, Santa Fe, New Mexico, May 16-18, 2018

    Data reduction pipelines for the Keck Observatory Archive

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    The Keck Observatory Archive (KOA) currently serves ~ 42 TB of data spanning over 20 years from all ten past and current facility instruments at Keck. Although most of the available data are in the raw form, for four instruments (HIRES, NIRC2, OSIRIS, LWS), quick-look, browse products generated by automated pipelines are also offered to facilitate assessment of the scientific content and quality of the data. KOA underwrote the update of the MAKEE package to support reduction of the CCD upgrade to HIRES, developed scripts for reduction of NIRC2 data and automated the existing OSIRIS and LWS data reduction packages. We describe in some detail the recently completed automated pipeline for NIRSPEC, which will be used to create browse products in KOA and made available for quicklook of the data by the observers at the telescope. We review the currently available data reduction tools for Keck data, and present our plans and anticipated priorities for the development of automated pipelines and release of reduced data products for the rest of the current and future instruments. We also anticipate that Keck's newest instrument, NIRES, which will be delivered with a fully automated pipeline, will be the first to have both raw and level-1 data ingested at commissioning

    Data and Metadata Management at the Keck Observatory Archive

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    A collaboration between the W. M. Keck Observatory (WMKO) in Hawaii and the NASA Exoplanet Science Institute (NExScI) in California, the Keck Observatory Archive (KOA) was commissioned in 2004 to archive data from WMKO, which operates two classically scheduled 10 m ground-based telescopes. The data from Keck are not suitable for direct ingestion into the archive since the metadata contained in the original FITS headers lack the information necessary for proper archiving. The data pose a number of challenges for KOA: different instrument builders used different standards, and the nature of classical observing, where observers have complete control of the instruments and their observations, lead to heterogeneous data sets. For example, it is often difficult to determine if an observation is a science target, a sky frame, or a sky flat. It is also necessary to assign the data to the correct owners and observing programs, which can be a challenge for time-domain and target-of-opportunity observations, or on split nights, during which two or more principle investigators share a given night. In addition, having uniform and adequate calibrations is important for the proper reduction of data. Therefore, KOA needs to distinguish science files from calibration files, identify the type of calibrations available, and associate the appropriate calibration files with each science frame. We describe the methodologies and tools that we have developed to successfully address these difficulties, adding content to the FITS headers and “retrofitting" the metadata in order to support archiving Keck data, especially those obtained before the archive was designed. With the expertise gained from having successfully archived observations taken with all eight currently active instruments at WMKO, we have developed lessons learned from handling this complex array of heterogeneous metadata. These lessons help ensure a smooth ingestion of data not only for current but also future instruments, as well as a better experience for the archive user

    The NASA Exoplanet Archive: Data and Tools for Exoplanet Research

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    We describe the contents and functionality of the NASA Exoplanet Archive, a database and tool set funded by NASA to support astronomers in the exoplanet community. The current content of the database includes interactive tables containing properties of all published exoplanets, Kepler planet candidates, threshold-crossing events, data validation reports and target stellar parameters, light curves from the Kepler and CoRoT missions and from several ground-based surveys, and spectra and radial velocity measurements from the literature. Tools provided to work with these data include a transit ephemeris predictor, both for single planets and for observing locations, light curve viewing and normalization utilities, and a periodogram and phased light curve service. The archive can be accessed at http://exoplanetarchive.ipac.caltech.edu.Comment: Accepted for publication in the Publications of the Astronomical Society of the Pacific, 4 figure
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