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GAVO – after one year. H.-M. Adorf & the GAVO team. GAVO’s Pillars. Publication and federation of datasets including theoretical ones Spatial matching & classification & visualization (NGSE) Grid computing. The GAVO Team. PI: Wolfgang Voges, MPE, Garching
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GAVO – after one year H.-M. Adorf & the GAVO team
GAVO’s Pillars • Publication and federation of datasets • including theoretical ones • Spatial matching & classification & visualization (NGSE) • Grid computing
The GAVO Team • PI: Wolfgang Voges, MPE, Garching • CoI: Matthias Steinmetz, AIP, Potsdam • Hans-Martin Adorf, MPE • Harry Enke, AIP • Gerard Lemson, MPE
Collaborations • MPE, Garching (Peter Schuecker) • AIP Potsdam • Canadian Virtual Obs. (CVO), Victoria • Universitaetssternw. Muenchen (USM) • MPA, Garching (Planck, …)
GAVO Work Areas • Publication of ROSAT datasets • REST-based SCS service (HTTP GET in; XML, CSV, HTML out) • SOAP-based SCS service • MCMCS Download Manager • Fuzzy spatial matcher • Grid-based detection of galaxy clusters • ROSAT matcher/classifier service
ROSAT All-Sky Survey (RASS) • BSC, FSC & Photons • VO-compatibility: • Input: Simple cone search • Output: VOTable, … • New features • Exposure times • Galactic & Cartesian coordinates • Healpix indices
MCMCS Download Manager • Tool … • … accesses registry at JHU • User … • … selects up to 70 distributed catalogues • … specifies one or more sky-locations • Tool … • … queries remote catalogues • … retrieves datasets (VOTables) for further processing
Fuzzy spatial matcher • Essential for data mining • Prototype features • Performs “fuzzy” match between pairs of source lists from different catalogues • Computes probability of real match based on astrometric uncertainties • Moving matcher into production use • Currently exported to Canadian Virtual Observatory • Feeding matches to ClassX classifier • Long-term goal: assemble an SED
Grid computing • What is Grid-computing? • Globus Toolkit, SGE, EJBs • WebServices • Detection of galaxy clusters • using RASS photons, SDSS • RASS source classification • using RASS B/FSC, SUMSS, NVSS, USNO
Galaxy-cluster detection • Search for galaxy clusters in heterogeneous databases • RASS photons • SDSS • Software • FORTRAN 90 code (data analysis) • Perl scripts (data/grid management) • Globus Toolkit
Galaxy-cluster detection • Components • Setup script • Sets up the directory structure • Distributes the software across the grid • Execution script • Triggers the parallel execution on the compute nodes • Data collection script • Retrieves the results from the compute nodes
Status • Perl scripts • Upgrading the RASS Photon DB • Soon integrate the SDSS mirror copy
RASS-source classifier • ClassX: international collaboration • T.A. McGlynn, A.A. Suchkov, E.L. Winter, R.J. Hanisch, R.L. White, F. Ochsenbein, S. Derriere, W. Voges, M.F. Corcoran • Requires data from several sky-surveys • X-ray: ROSAT BSC+FSC • Optical: USNO, (SDSS) • Infrared: (2MASS) • Radio: FIRST, NVSS, SUMSS • Distributed multi-wavelength VO-application
RASS-source classifier • State & session management • Using Java Servlet session mechanism • Internal abstract state machine • Strong points • End-to-end VO-application • Works with lists of objects / sky-coordinates • Accesses several distributed databases • Uses deterministic matcher (at Vizier and SDSS) • Uses probabilistic matcher (at GAVO) • Uses data analysis service (at NASA)
RASS-source classifier • Future work • Use IVOA-standards or protocols • VOTable • WSDL, SOAP-based Web Services • Add graphics • Multi-threaded • Modularize, generalize and make S/W configurable
RASS-source classifier • Open questions • Is an HTML form-based GUI sufficiently powerful to control a complex grid application? • What are the user expectations wrt the workflow? • Is there a standard workflow that one could use / agree upon?
Conclusion • GAVO is a small, but ambitious project • Two Grid applications • Detection of galaxy clusters • Globus Toolkit • Classification of ROSAT sources • Based on WebServices
References • GAVO Mid-Term Report, 90 pages, http://www.g-vo.org (soon) • Detection of X-ray Clusters of Galaxies by Matching RASS Photons and SDSS Galaxies within GAVO, P. Schuecker, H. Boehringer, W. Voges, A&A (submitted) • Automated classification of ROSAT sources using heterogeneous multiwavelength catalogs, T.A. McGlynn et al., ApJ (submitted)