J/ApJ/719/1672ivo://CDS.VizieR/J/ApJ/719/1672doi:10.26093/cds/vizier.17191672CDSHennawi J.F.Myers A.D.Shen Y.Strauss M.A.Djorgovski S.G.Fan X.,Glikman E.Mahabal A.Martin C.L.Richards G.T.Schneider D.P.,Shankar F.2018-01-08T06:37:40Z2012-07-09T09:23:57ZCDS support team

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

cds-question@unistra.frquasarsvisible-astronomysloan-photometryspectroscopyredshiftedThe clustering of quasars on small scales yields fundamental constraints on models of quasar evolution and the buildup of supermassive black holes. This paper describes the first systematic survey to discover high-redshift binary quasars. Using color-selection and photometric redshift techniques, we searched 8142deg^2^ of Sloan Digital Sky Survey imaging data for binary quasar candidates, and confirmed them with follow-up spectroscopy. Our sample of 27 high-redshift binaries (24 of them new discoveries) at redshifts 2.9<z<4.3 with proper transverse separations 10kpc<R_T_<650kpc increases the number of such objects known by an order of magnitude. Eight members of this sample are very close pairs with R_T_<100kpc, and of these close systems four are at z>3.5. The completeness and efficiency of our well-defined selection algorithm are quantified using simulated photometry and we find that our sample is ~50% complete.2010ApJ...719.1672Hhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/719/1672CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/260 : The SDSS-DR7 quasar catalog (Schneider+, 2010)J/ApJ/678/635 : Spectroscopy of quasar binary candidates (Myers+, 2008)J/AJ/131/1 : Binary quasars in the SDSS (Hennawi+, 2006)http://www.sdss.org/ : SDSS home pagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/719/1672https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/719/1672http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/719/1672https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/719/1672https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/719/1672http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/719/1672GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/719/1672/table3 (High-redshift binary quasars in the SDSS imaging footprint)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/719/1672/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/719/1672/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/719/1672/table3?GETtext/xml+votable180.050000true1.21114167-8.747077780.0055555555555555566/4575 5030 5439 5502 5714 5940 8697 8951 9978 10393 10556 10641 10732 11041 17259 25935 26239 27062 27078 27549 27565 28011 28149 28622 31546 31636 316862.040811542443644e-19 6.090060298487514e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/719/1672?format=asciiOpticaldefaultJ/ApJ/719/1672/table3High-redshift binary quasars in the SDSS imaging footprintSDSSSDSS-DR7 IAU namemeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordint[HMS2010]Brighter quasar designation (SDSS JHHMM+DDMMA or PSS JHHMM+DDMMA) (1)meta.id;phys.atmol.configurationcharf_[HMS2010][a] PSS quasar (2)meta.codecharRAJ2000Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of declination (J2000)pos.eq.dec;meta.mainumag? SDSS u-band magnitude (3)magphot.mag;em.opt.Ufloatnullablegmag? SDSS g-band magnitude (3)magphot.mag;em.opt.Bfloatnullableu_rmag[~] Uncertainty flag on rmagmeta.code.errorcharrmag? SDSS r-band magnitude (3)magphot.mag;em.opt.Rfloatnullableimag? SDSS i-band magnitude (3)magphot.mag;em.opt.Ifloatnullablezmag? SDSS z-band magnitude (3)magphot.mag;em.opt.Ifloatnullablechi2s? The minimum stellar locus distance ({chi}^2^_star_)stat.fit.chi2floatnullablechi2p? Quasar locus distance ({chi}^2^_phot_)stat.fit.chi2floatnullablezRedshiftsrc.redshiftfloate_zEstimation of the redshift uncertaintykm/sstat.error;src.redshiftintDelV? Velocity difference {Delta}V between the two members of a pair (primary only)km/sphys.veloc;arith.diffintnullableDelT? Angular separation {Delta}{theta}arcsecpos.angDistancefloatnullableRT? Transverse proper separationkpcpos.distanceintnullableDR7Cross-match with the SDSS-DR7 photometric catalog within 1"meta.ref.urlcharSloanDisplay the SDSS online data for this quasarmeta.ref.urlcharSimbadSimbad column added by the CDSmeta.refchar