J/ApJ/766/60ivo://CDS.VizieR/J/ApJ/766/60doi:10.26093/cds/vizier.17660060CDSGezari S.Martin D.C.Forster K.Neill J.D.Huber M.Heckman T.,Bianchi L.Morrissey P.Neff S.G.Seibert M.Schiminovich D.,Wyder T.K.Burgett W.S.Chambers K.C.Kaiser N.Magnier E.A.,Price P.A.Tonry J.L.2015-01-12T11:29:44Z2014-12-10T15:52:37ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frultraviolet-astronomyactive-galactic-nucleivariable-starssurveysredshiftedinfrared-photometryvisible-astronomybroad-band-photometryx-ray-sourcesWe present the selection and classification of over a thousand ultraviolet (UV) variable sources discovered in ~40deg^2^ of GALEX Time Domain Survey (TDS) NUV images observed with a cadence of 2 days and a baseline of observations of ~3 years. The GALEX TDS fields were designed to be in spatial and temporal coordination with the Pan-STARRS1 Medium Deep Survey, which provides deep optical imaging and simultaneous optical transient detections via image differencing. We characterize the GALEX photometric errors empirically as a function of mean magnitude, and select sources that vary at the 5{sigma} level in at least one epoch. We measure the statistical properties of the UV variability, including the structure function on timescales of days and years. We report classifications for the GALEX TDS sample using a combination of optical host colors and morphology, UV light curve characteristics, and matches to archival X-ray, and spectroscopy catalogs. We classify 62% of the sources as active galaxies (358 quasars and 305 active galactic nuclei), and 10% as variable stars (including 37 RR Lyrae, 53 M dwarf flare stars, and 2 cataclysmic variables). We detect a large-amplitude tail in the UV variability distribution for M-dwarf flare stars and RR Lyrae, reaching up to |{Delta}m|=4.6mag and 2.9mag, respectively. The mean amplitude of the structure function for quasars on year timescales is five times larger than observed at optical wavelengths. The remaining unclassified sources include UV-bright extragalactic transients, two of which have been spectroscopically confirmed to be a young core-collapse supernova and a flare from the tidal disruption of a star by dormant supermassive black hole. We calculate a surface density for variable sources in the UV with NUV<23mag and |{Delta}m|>0.2mag of ~8.0, 7.7, and 1.8deg^-2^ for quasars, active galactic nuclei, and RR Lyrae stars, respectively. We also calculate a surface density rate in the UV for transient sources, using the effective survey time at the cadence appropriate to each class, of ~15 and 52deg^-2^/yr for M dwarfs and extragalactic transients, respectively.2013ApJ...766...60Ghttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/766/60CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/312 : GALEX-DR5 (GR5) sources from AIS and MIS (Bianchi+ 2011)III/250 : The VIMOS VLT deep survey (VVDS-DEEP) (Le Fevre+ 2005)II/255 : SWIRE ELAIS N1 Source Catalogs (Surace+, 2004)IX/10 : ROSAT All-Sky Bright Source Catalogue (1RXS) (Voges+ 1999)J/ApJS/201/30 : The Chandra COSMOS survey. III. (Civano+, 2012)J/ApJ/750/99 : The Pan-STARRS1 photometric system (Tonry+, 2012)J/ApJ/734/13 : GALEX ultraviolet halos around bright stars (Murthy+, 2011)J/AJ/141/97 : SDSS DR7 M dwarfs (West+, 2011)J/MNRAS/411/2770 : Hot white dwarfs in GALEX-DR5 (Bianchi+, 2011)J/AJ/140/1987 : SDSS-GALEX QSO catalog (Hutchings+, 2010)J/ApJ/708/717 : Light curve templates of RR Lyrae stars (Sesar+, 2010)J/ApJ/696/1195 : COSMOS AGN spectroscopic survey. I. (Trump+, 2009)J/ApJS/184/218 : The zCOSMOS 10k-bright spectroscopic sample (Lilly+, 2009)J/ApJS/180/102 : AEGIS-X: Chandra deep survey (Laird+, 2009)J/AJ/137/4517 : UVOT light curves of supernovae (Brown+, 2009)J/AJ/136/259 : Second GALEX UV variability cat. (GUVV-2) (Wheatley+, 2008)J/ApJ/676/944 : GALEX & CFHTLS cand. tidal disruption events (Gezari+, 2008)J/ApJS/173/293 : UV-Optical galaxy color-magnitude diagram I. (Wyder+, 2007)J/ApJS/173/673 : M dwarf UV flares in GALEX (Welsh+, 2007)J/ApJS/172/383 : AGN candidates in the COSMOS field (Trump+, 2007)J/ApJS/172/70 : zCOSMOS-bright catalog (Lilly+, 2007)J/ApJS/172/29 : XMM-Newton survey in COSMOS field. I. (Hasinger+, 2007)J/AJ/133/1780 : GALEX/SDSS quasar catalog (Trammell+, 2007)J/AJ/131/2373 : Extended Chandra Deep Field-South survey (Virani+, 2006)J/AJ/130/825 : GALEX ultraviolet variability catalog (Welsh+, 2005)J/ApJS/161/21 : Extended Chandra Deep Field-South survey (Lehmer+, 2005)J/MNRAS/356/568 : Deep Chandra survey of the Groth Strip (Nandra+, 2005)J/ApJ/633/638 : 315 SDSS variable quasar sample (Wilhite+, 2005)J/A+A/439/413 : XMDS/VVDS 4{sigma} catalogue (Chiappetti+, 2005)J/A+A/428/1043 : Redshifts from VIMOS VLT Deep Survey (Le Fevre+, 2004)J/MNRAS/343/293 : ELAIS deep X-ray survey. I. (Manners+, 2003)J/ApJS/139/369 : Chandra Deep Field South. 1 Ms catalog (Giacconi+, 2002)J/MNRAS/268/305 : Variability of optically selected quasars (Hook+ 1994)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/766/60https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/766/60http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/766/60https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/766/60https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/766/60http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/766/60GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/766/60/table4 (GALEX Time Domain Survey (TDS) catalog)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/766/60/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/766/60/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/766/60/table4?GETtext/xml+votable180.050000true216.162254.09110.0055555555555555565/2538 2856 2857 4422 4423 4758 6814 8983 8989 6/10146 10147 10150 10151 10156 10157 10158 10743 10749 11403 11406 11432 11433 11436 11520 11521 11524 17682 17683 17686 17713 17716 17717 19023 19026 19027 19030 19036 19038 19056 19057 19060 27239 27244 27245 27247 27250 27251 27262 27333 27344 27345 27348 35931 35953 36104 36106 36107 36128 36130https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/766/60?format=asciiX-rayUVOpticalInfrareddefaultJ/ApJ/766/60/table4GALEX Time Domain Survey (TDS) catalogl_DmmaxLimit flag on Dmaxmeta.code.errorcharl_mlowLimit flag on mlowmeta.code.errorcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDGALEX TDS name (fieldname_MOSpointing-NN)meta.id;meta.maincharRAJ2000Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.mainmlow[17.9/23.1] Low-state GALEX/NUV AB magnitude corrected for Galactic extinctionmagphot.mag;em.UVfloatDmmax[0.2/4.6] Maximum amplitude of NUV variability |{Delta}m_max_|magsrc.var.amplitude;em.UV.200-300nmfloatl_sigintLimit flag on sigintmeta.code.errorcharsigint[0/3.6] Intrinsic rms scatter {sigma}_int_magstat.stdevfloatl_SdLimit flag on Sdmeta.code.errorcharSd[0/1.5]? Structure function on days (3)magsrc.var.indexfloatnullablel_SyLimit flag on Symeta.code.errorcharSy[0/4.1]? Structure function on years (3)magsrc.var.indexfloatnullableLC[VF] Light curve type: V=stocharstic, F=flaringmeta.code;src.varcharMphOptical host morphology: pt=point, ext=extendedsrc.class.starGalaxycharrmag[8.8/45.3]? Optical host r-band AB magnitude corrected for Galactic extinctionmagphot.mag;em.opt.RfloatnullableOTOptical color class (1)meta.code.classcharz[0/4.1]? Redshiftsrc.redshiftfloatnullableX[X ] X-ray source matchmeta.codecharClassClassification (2)src.classchar