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Scientific Use Cases to be implemented to IVOQL. Masahiro Tanaka and JVO team (NAOJ) IVOA Interoperability 14 May 2003. Major Query items. Fundamental dimensions position with coordinate system wavelength time flux / apparent magnitude Other parameters redshift
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Scientific Use Cases to be implemented to IVOQL Masahiro Tanaka and JVO team (NAOJ) IVOA Interoperability 14 May 2003 Scientific Use Cases - Masahiro Tanaka
Major Query items • Fundamental dimensions • position with coordinate system • wavelength • time • flux / apparent magnitude • Other parameters • redshift • distance (from parallax / photometric / redshift) • absolute magnitude • … • Attributes • object names • object types (star / galaxy / …) • instrument (telescope / detector / filter / …) • … Scientific Use Cases - Masahiro Tanaka
Use Cases • Follow-up • Search for particular objects • Search for moving objects • Line matching Scientific Use Cases - Masahiro Tanaka
Use Case 1: Follow-up Obtain supplemental data of objects you have observed • Targets • Gamma-ray burst • Super Nova • AGN • … • Query • Position • Time • Cross-match Scientific Use Cases - Masahiro Tanaka
Example of Query forFollow-up data select y.id, c.ra, c.dec, c.vmag from public_catalog c, your_data y, where XMATCH(c, y) < 5 arcsec and c.obs_time between TIME(“2003-05-12 09:00:00”) and TIME(“2003-05-17 17:00:00”) Scientific Use Cases - Masahiro Tanaka
Use Case 2:Search for particular objects Find unknown objects with particular features • Targets • Brown dwarf • Gravitational lens • Metal-poor stars • Binaries, Planetary systems • … • Query • Color / Line • Cross-match Scientific Use Cases - Masahiro Tanaka
Example of search forbrown dwarf candidate • Brown dwarf can be observed in IR, not in Visual select i.id, i.ra, i.dec, i.kmag from ir_cat i, visual_cat v where XMATCH(i !v) < 5 arcsec and i.jmag - i.kmag > 1 Scientific Use Cases - Masahiro Tanaka
Use Case 3:Search for moving objects • Targets • Asteroid • Comet • … • Query • Position • Time • Cross-matching Scientific Use Cases - Masahiro Tanaka
Example of search formoving objects select c1.ra, c1.dec, c1.vmag, c2.ra, c2.dec, c2.vmag from cat1 c1, cat2 c2 where XMATCH(c1, !c2) < 30 arcsec and XMATCH(!c1, c2) < 30 arcsec and ABS(c1.vmag - c2.vmag) < 2 cat1 cat2 Scientific Use Cases - Masahiro Tanaka
Use Case 4:Line matching select m.molecule, m.mode, m.frequency, y.strength from your_data y, lte_model_20K m where LINEMATCH(y, m) < 0.1 GHz and y.sn > 3 LINEMATCH can work with Doppler shift. more than ABS(m.frequency - y.frequency) < 0.1 GHz Scientific Use Cases - Masahiro Tanaka
Summary of Use Cases Cross-match is essential for astronomical use • XMATCH: in position • LINEMATCH: in wavelength or frequency Scientific Use Cases - Masahiro Tanaka
Data analysis • How to query if columns are not provided? • e.g., only images/spectra are provided Data analysis function will be needed • Data analyses: • source/line extraction • morphology analysis • classification • data mining • Open question: • VOQL supports data analysis? Scientific Use Cases - Masahiro Tanaka