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AstroGrid RVO as a community center. Distant galaxy discovery problem. Alexey Vovchenko ( CMC MSU ) RVO Workshop 10.04.2006. AstroGrid RVO as a community center.
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AstroGrid RVO as a community center.Distant galaxy discovery problem Alexey Vovchenko (CMCMSU) RVO Workshop 10.04.2006
AstroGrid RVO as a community center • AstroGrid RVO is organized as a community center intended for solving different astronomicalproblems over distributed repositories of astronomical data accumulated around the world (observations data, problem solution results, services of data and information analysis). • Put into operation, AstroGrid RVO is considered to be one of the first steps in reaching the objectives of Russian Virtual Observatory informational infrastructure (RVOII). • The Center has become operational at IPI RAS since October 2005 on the base of the AstroGrid system, developed at the UK and generously granted by the authors to be used for the RVO.
Basic facilitiesof the AstroGrid RVO • Facilities for problem solving by scientists over information accumulated in the VO (including tools for workflow management, tools for managing common data spaces for the group work, special tools for astronomical data analysis); • Tools for creating new services for information analysis; • Facilities for setting data management systemsanddata setssupported by such systemsat the community center; • Tools for searching in the catalogues of the International Virtual Observatory based on the IVOA standards; • Tools for publishing astronomical observations results, problem solving results, software services for the RVO Metadata Registries in compliance with the IVOA standards.
The first trial of the AstroGrid RVO installation at IPI RAS • In August - September 2005 applying the AstroGrid RVO installation at IPI RAS, as the joint effort of the Special Astrophysical Observatory of RAS (SAO RAS) and IPI RAS, the information processing facilities have been developed and tested for solving the Distant galaxy discovery problem • The problem statement has been provided by Olga Zhelenkova (SAO RAS)
The problem overview • The first astronomical problem that has been designed by IPI RAS together with the Special Astrophysical Observatory of RAS (SAO RAS) applying AstroGrid and Aladin is a distant galaxy discovery in the sky strip investigated in the “Cold” deep survey with the RATAN-600 (large Russian radio telescope). • For the beginning we used RCcatalogue as a list of radio sources. • The approach applied looks fairly simple. • We need to select optical sources with certain properties taken from DR 3 SDSS and crosssmatch them with the RCcatalogue. • The result of the crossmatch may contain candidates for distant galaxies that should be analyzed further applying their images and Aladin capabilities.
Information processing steps at distant galaxy search • Radio sources search in RCcatalogue in the given sky area • Optical sources search in SDSS DR3 catalogue in the given sky area • Optical sources selection on the base of predicates taking into account color values of sources • CrossMatch of the radio and optical sources, obtained at the previous steps • Download the respective images from FIRST and SDSS images archives, and provide their superposition. Analyze the result
CEA-application, MySpaceandDSA • CEA-interfaceprovides access from the AstroGrid system to the external applications • Application, accessed from the AstroGrid system by the CEA-interface, is known as CEA-Application • MySpaceis a storage file system for a user data: queries, workflows, intermadiate results and final results • DSAprovides access from the AstroGrid system to local data bases (PostgreSQL and MySQL)
Information processing steps in AstroGrid system and Aladin AstroGrid Workflow: • Step1. RCcatalogue Query • Step2. SDSS Query • Step3. CrossMatch the results, obtained on pervious steps • Step4. Download images and provide superposition of them Aladin: • Step5. Image analysisby a specialist
Step1. RCcatalogue Query • CEA-Application is launchedwhich execute the ADQL query to the data base, containing the RCcatalogue • The local copy of RCcatalogue has been created at PostgreSQL, and formed as an AstroGrid DSA component • Result obtained in the VOTable format has been automatically placed into the MySpace
Step1: Example of the ADQL query SELECT crd.ra, crd.de, cat.name FROM RCCatalog as cat, CoordEQJ as crd WHERE cat.coord_id = crd.coord_id
Step2. SDSS Query • CEA-Application is launched, which, applying the web-service provided by SDSS(CasService http://voservices.net/CasService/ws_v1_0/CasService.asmx ),executesthe query • Result obtained in the VOTable format has been automatically placed into the MySpace
Step2: Example of a query SELECT ra=cast(ra as real), [dec]=cast([dec] as real), objid, u, g, i, r, z, colorIndexURG=(u+r)/2.0-g FROM PhotoPrimary WHERE ra BETWEEN 225.0 AND 225.5 AND [dec] BETWEEN 4.0 AND 5.61 AND r BETWEEN 15.0 AND 23.0
Step3. CrossMatch the results • CrossMatch the result of two previous steps using CrossMatcher provided by AstroGrid (ivo://org.astrogrid/CrossMatcher). • Result obtained in VOTable format has been automatically placed into the MySpace • The result of the CrossMatch may contain candidates for distant galaxies
Aladin XMatch Results CEA NVSS DSS FIRST SDSSDR3 2MASS Step4. Downloading images and providing superposition of them Script (ra,dec) Aladin stack
Aladin Script • reset; grid; • get DSS.ESO(DSS1,14.1,14.1) + adress + 5'; sync; • get NVSS(0.2,15.0,Stokes I,Sine) + adress + 5'; • sync; contour 4; • get FIRST(10) + adress + 5'; • sync; contour 4; • get SDSSDR3cat + adress + 1'; • sync; • get VizieR(2mass) + adress + 1'; • sync; • show 1; hide NVSS FIRST; • backup st.aj
Step4. Downloading images and providing superposition of them
Step5. Image analysisby a specialist • Launching Aladin (version 3.030_votech) • Launching Workbench • Opening Aladin stack, saved in MySpace on a previous step • Viewing, analyzing, probably editing obtained images using Aladin tools
Distant galaxy discovery tools (reported in the talk) applying the AstroGrid RVO and Aladin will be demonstrated tomorrow at the demo session (starts at 11:50)
Как стать пользователем системы АстроГрид РВО • Для того, чтобы стать пользователем АстроГрид РВО, необходимо послать электронное письмо по адресу ssa@ipi.ac.ru. Письмо должно содержать следующую информацию: • имя, фамилия, e-mail, [почтовый адрес, телефон] контактного лица, желающего зарегистрировать пользователя или группу пользователей в АстроГрид РВО; • наименование, [почтовый адрес, телефон] организации, которую представляет контактное лицо; • список имен пользователей АстроГрид РВО (имя пользователя должно состоять из символов латинского алфавита, числом не менее 5); • список желаемых имен групп и желаемое разбиение пользователей на группы. • В случае, если вся необходимая информация предоставлена в корректном виде, пользователи (группы пользователей) будут зарегистрированы в сообществе ipi.ac.ru АстроГрид РВО. По указанному контактному электронному адресу будут высланы пароли для входа в портал АстроГрид РВО. Вход в портал осуществляется по адресу • http://astrogrid.ipi.ac.ru:8080/astrogrid-portal/
Как стать пользователем системы АстроГрид РВО • Базы данных, а также программные сервисы могут быть размещены на серверах АстроГрид РВО в ИПИ РАН. Заявку на размещение необходимо послать по адресу ssa@ipi.ac.ru. Заявка должно содержать следующую информацию: • имя, фамилия, e-mail, [почтовый адрес, телефон] контактного лица, желающего разместить сервис или базу данных на сервере АстроГрид РВО; • наименование, [почтовый адрес, телефон] организации, которую представляет контактное лицо; • краткое описание сервиса или базы данных, предлагаемых для размещения. • Дальнейшее согласование по вопросам размещения будет проводиться по электронной почте. • Согласование о порядке проведения возможных консультаций по пользованию АстроГрид РВО осуществляется по электронной почте ssa@ipi.ac.ru или телефонам в Москве (495) 1292098, 1291843.