测光红移星表数据描述.doc

COSMOS Photometric Redshift Catalog (mag limit 25) DefinitionsThe COSMOS Archive serves data taken for the Cosmic Evolution Survey (COSMOS) project.COSMOS is an astronomical survey designed to probe the formation and evolution of galaxies as a function of cosmic time (redshift) and large scale structural environment. The survey covers a 2 square degree equatorial field with imaging by most of the major space-based telescopes (Hubble, Spitzer, GALEX, XMM, Chandra) and a number of large ground based telescopes (Subaru, VLA, ESO-VLT, UKIRT, NOAO, CFHT, and others).IRSA serves the COSMOS archive using the following search methods: Spatial search on all images and small catalogs, using Atlas Advanced search on only the larger catalogs, using Gator COSMOS Photometric Redshift Catalog, version 1.5, mag limig 25, Column DefinitionsGator serves the COSMOS October 2008 Photometric Redshift Catalog (55 columns 50 delivered + 5 IRSA-created, 385,065 data rows). The column descriptions can be found below. Please also see thephotz catalog README file for more information about the catalog intypeunitsdescriptionIdintnumberCatalog ID number per tiletileintnumberImage tile which contains this objectradoubledegRight Ascension (J2000)decdoubledegDeclination (J2000)zp_bestdoubleredshiftzp_best = zgal if galaxy (column 7)zp_best = 0 if starzp_best = 9.99 if Xray (Use the photo-z values from Salvato et al. 2008, released separately)zp_best = 99.0 if IA25.5 (faint sources with a lower photo-z accuracy, needs to be handle with extreme care)zp_best = -99 if in a masked areatypeintnumbertype = 0 if galaxytype = 1 if startype = 2 if Xray sourcetype = 3 if IA25.5 (faint sources with a lower photo-z accuracy, needs to be handle with extreme care)type = -99 if masked areazp_galdoubleredshiftphoto-z using the galaxy templates (every source has a redshift)zl68_galdoubleredshiftlower limit, 68% confidence levelzu68_galdoubleredshiftupper limit, 68% confidence levelzl99_galdoubleredshiftlower limit, 99% confidence levelzu99_galdoubleredshiftupper limit, 99% confidence levelchi_galdoublenumberreduced chi2 (-99 if less than 3 filters)mod_galintnumberbest fit template (1-8 Ell-S0, 9-15 Sa-Sc, 16-19 Sd-Sdm from Polletta et al., =20 from BC03). ebvdoublenumberadditional extinction E(B-V) (Prevot et al. for templates 24)zp_secdoubleredshiftsecond photo-z solutionchi_secdoublenumberreduced chi2 for the second photo-z solutionmod_secintnumbertemplate for the second photo-z solutionebv_secdoublenumberadditional extinction for the second photo-z solutionmod_starintnumbermodel for the star librarychi_stardoublenumberreduced chi2UmagdoublemagCFHT u* aperture magnitude (3 aperture)BmagdoublemagSubaru B aperture magnitude (3 aperture)VmagdoublemagSubaru V aperture magnitude (3 aperture)GmagdoublemagSubaru g+ aperture magnitude (3 aperture)RmagdoublemagSubaru r+ aperture magnitude (3 aperture)ImagdoublemagSubaru i+ aperture magnitude (3 aperture)ZmagdoublemagSubaru z+ aperture magnitude (3 aperture)ICmagdoublemagCFHT i aperture magnitude (3 aperture)JmagdoublemagUKIRT J aperture magnitude (3 aperture)KmagdoublemagCFHT K aperture magnitude (3 aperture)eUdoublemagCFHT u* error on the magnitudeeBdoublemagSubaru B error on the magnitudeeVdoublemagSubaru V error on the magnitudeeGdoublemagSubaru g+ error on the magnitudeeRdoublemagSubaru r+ error on the magnitudeeIdoublemagSubaru i+ error on the magnitudeeZdoublemagSubaru z+ error on the magnitudeeICdoublemagCFHT i error on the magnitudeeJdoublemagUKIRT J error on the magnitudeeKdoublemagCFHT K error on the magnitudeflagBintnumbermask in the B band, 0 goodflagVintnumbermask in the V band, 0 goodflagiintnumbermask in the I band, 0 goodflagzintnumbermask in the Z band, 0 goodflagDintnumbermask for the deep area, 0 goodNbFiltintnumberNumber of filters used in the photo-z fittingI_a