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TimeServerAndrew DrakeRobyn AllsmanDavid GassonMark HuberKathy Vivas

US NATIONAL VIRTUAL OBSERVATORY

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The Working Astronomer’s Motivation for a TD Object Tool

• Optical Projects– MACHO, EROS, OGLE, MOA, EROS– SuperMacho, ESSENCE– LONEOS, ROTSE– FSVS, QUEST1, PQ, MEGACAM– PANSTARRS, LSST

– Specific Source – • variable stars cluster studies• radial velocity planet searches• Pulsar studies• HST, Chandra, EUVE...

NVO Summer School, Aspen 9-Sep-2005

The Working Astronomer’s Motivation for a TD Object Tool

•Science Goals– Microlensing– Planet Searches– Quasar Variability– Variable Star Zoo

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Time Server

• The goal– Provide VO-enabled access to time-domain data

• Why?In anticipation of the upcoming TD surveys– Provide uniform access to precursor TD datasets– Foster tool development oriented on TD datasets

• How? – Develop

• A registry of time-domain datasets• A generic interface for TD data extraction • A client enabling:

– Registry lookup of TD datasets meeting specified criterion– Retrieval of TD datasets meeting those criterion– Display/Save/Analysis of those TD dataset

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T.D. RegistryService

T.D. ObjectExtractorService

TD ObjectDataScope ADQL Fronted

TD DatabaseServers

The Future

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T.D. RegistryService

T.D. ObjectExtractorService

Quest RR LyraeTD Extractor

Service

MACHO TD Extractor

Service

FetchEm

Favorite DBTD Extractor

Current Reality

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Reality of Current Database Configurations

• Fully ADQL enabled– Quest RR Lyrae dataset

• Partially ADQL enabled– Macho

• ADQL enabled for variable star cone search• REST/http for lightcurve retrieval

• http/GET enabled– NSVS/ROTSE– OGLE– AAVSO– Quest1

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Fully ADQL-enabled TD Extractor

• One stop shopping. Generally a TD dataset contains at least two tables:

• Overarching info on each star (ra/dec/starId/…)• Measurements for each Observation in T.D. series

– A single query should suffice to extract the T.D data **

Select o.* from Gentable g, Obstable oWhere point(g.ra, g.dec) within region(<ra>,<dec>,<radius>) and o.starId = g.starId and <starttime> < o.time < <endtime>

** Maybe … don’t know if ADQL syntax supports this.

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Partially ADQL-enabled TD Extractor for MACHO TD dataset

• MACHO TD Server – integrates VO/non-VO enabled servers – to retrieve TD lightcurves based on constraints

• The Macho Variable Star catalog is now ADQL-enabled via ‘SkyNodeSoap’ service Cone search on ra/dec + constraints provides lookup

key for TD series retrieval

• Lightcurve retrieval is http/GET accessible– Responses must be

• scrubbed to extract relevant data • reformatted into VOTable for return

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Near Term Direction

• Use the SSAP time domain definition for VO object construction

• Contact other TD providers to gauge their interest in VO-enabling their data– Wrap other TD http/GET datasets as desired

• Build the generic TD Object server• Build a simple client for TD Object

retrieval– Morph that into a TD Datascope

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