J/AJ/146/10ivo://CDS.VizieR/J/AJ/146/10doi:10.26093/cds/vizier.51460010CDSTitov O.Stanford L.M.Johnston H.M.Pursimo T.Hunstead R.W.,Jauncey D.L.Maslennikov K.Boldycheva A.2017-11-10T11:16:08Z2014-06-06T07:54:57ZCDS support team

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

cds-question@unistra.frvery-long-baseline-interferometryradio-galaxiesquasarsbl-lacertae-objectsspectroscopyredshiftedContinuing our program of spectroscopic observations of International Celestial Reference Frame (ICRF) sources, we present redshifts for 120 quasars and radio galaxies. Data were obtained with five telescopes: the 3.58m European Southern Observatory New Technology Telescope, the two 8.2m Gemini telescopes, the 2.5m Nordic Optical Telescope (NOT), and the 6.0m Big Azimuthal Telescope of the Special Astrophysical Observatory in Russia. The targets were selected from the International VLBI Service for Geodesy & Astrometry candidate International Celestial Reference Catalog which forms part of an observational very long baseline interferometry (VLBI) program to strengthen the celestial reference frame. We obtained spectra of the potential optical counterparts of more than 150 compact flat-spectrum radio sources, and measured redshifts of 120 emission-line objects, together with 19 BL Lac objects. These identifications add significantly to the precise radio-optical frame tie to be undertaken by Gaia, due to be launched in 2013, and to the existing data available for analyzing source proper motions over the celestial sphere. We show that the distribution of redshifts for ICRF sources is consistent with the much larger sample drawn from Faint Images of the Radio Sky at Twenty cm (FIRST) and Sloan Digital Sky Survey, implying that the ultra-compact VLBI sources are not distinguished from the overall radio-loud quasar population. In addition, we obtained NOT spectra for five radio sources from the FIRST and NRAO VLA Sky Survey catalogs, selected on the basis of their red colors, which yielded three quasars with z>4.2013AJ....146...10Thttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/146/10CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/259 : 6dF galaxy survey final redshift release (Jones+, 2009)I/323 : International Celestial Reference Frame 2, ICRF2 (Ma+, 2009)VIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)J/ApJ/748/49 : Optical spectroscopy of 1LAC broad-line blazars (Shaw+, 2012)J/AJ/141/182 : Radio and optical properties of QSOs (Kimball+, 2011)J/A+A/506/1477 : Radio source distribution (Titov+, 2009)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/146/10https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/146/10http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/146/10https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/146/10https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/146/10http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/146/10GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/146/10/table1 (Observed emission lines)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/146/10/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/146/10/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/146/10/table1?GETtext/xml+votable180.050000true6.351030833-22.4632211110.005555555555555556Cone search capability for table J/AJ/146/10/table2 (Probable BL Lac objects)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/146/10/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/146/10/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/146/10/table2?GETtext/xml+votable180.050000true7.1731775-70.7544238890.005555555555555556Cone search capability for table J/AJ/146/10/table3 (Objects with low signal-to-noise spectra)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/146/10/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/146/10/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/146/10/table3?GETtext/xml+votable180.050000true31.889163333-24.0339472220.0055555555555555566/307 1051 1767 1787 5167 5495 5850 5984 7512 8604 10095 10116 10460 10815 10954 11521 15807 16774 17725 18641 18957 19104 19281 19493 20157 20304 20377 20678 20703 20735 20768 20908 20912 21010 21147 21188 21191 21197 21554 21574 21793 21903 22563 22768 22799 22856 22978 24099 24326 24333 24346 24357 25211 25299 25511 26755 26834 26852 26905 27012 27124 27138 27417 29357 29772 30050 32808 32871 32969 33008 33176 33238 33259 33398 33412 33489 33626 33712 33825 33833 33967 33996 34009 34012 34050 34086 34489 34665 34683 34710 35136 35281 35918 36176 36282 36391 36735 36841 36871 36910 36916 36988 37062 37091 37138 37190 37529 37534 37602 37777 38128 38199 38303 38355 38397 38502 38519 38918 38930 38942 39023 39740 40217 40281 40300 40339 40354 40520 40607 40635 40637 40642 40873 40874 40891 40902 41991 44170 44944 45159 45165 45415 45424 45482 45923 46123 46175 46232 46445 46931 47277 47969 48120 48300 49037https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/146/10?format=asciiOpticalRadiodefaultJ/AJ/146/10/table1Observed emission linesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBNameIVS (International VLBI Service for geodesy & astrometry) source name (BHHMM+DDd)meta.id;meta.maincharprimaryn_BName[*] A note in Section 3.2 for this objectmeta.notecharRAJ2000Hour of Right Ascension (J2000) (G1)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000) (G1)pos.eq.dec;meta.mainNeNumber of emission lines observed for this sourcemeta.ref.urlintnullableTelTelescope code (BTA, GS, GN, NOT, NTT) (G2)meta.code;instr.telcharLineEmission line identifiermeta.id;spect.linelam.0Rest wavelength; in {AA}0.1nmem.wlfloatlambda[3744/8666] Observed wavelength; in {AA}0.1nmem.wlfloatf_lambda[n] Line not used for redshift determinationmeta.codechar<z>Mean redshiftsrc.redshift;pos.heliocentricfloate_<z>? Uncertainty in zstat.error;src.redshiftfloatnullableu_<z>[:] Uncertainty flag in zmeta.code.error;src.redshiftcharf_<z>[S] Flag for single-line redshiftmeta.codecharzp? Previously determined redshiftsrc.redshift;pos.heliocentricfloatnullabler_zpReference for pz (1)meta.ref;pos.framecharICRF2Cross-match with the International Celestial Reference Frame 2 (ICRF2; Ma et al., 2009, cat. I/323) within 1.5"meta.ref.urlintnullableSimbadSimbad column added by the CDSmeta.ref.urlcharJ/AJ/146/10/table2Probable BL Lac objectsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBNameIVS (International VLBI Service for geodesy & astrometry) source name (BHHMM+DDd)meta.id;meta.maincharRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000) (G1)pos.eq.dec;meta.mainTelTelescope code (GS, GN, NTT) (G2)meta.code;instr.telcharSimbadSimbad column added by the CDSmeta.ref.urlcharJ/AJ/146/10/table3Objects with low signal-to-noise spectrarecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBNameIVS (International VLBI Service for geodesy & astrometry) source name (BHHMM+DDd)meta.id;meta.maincharRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000) (G1)pos.eq.dec;meta.mainTelTelescope code (GS, GN, NTT) (G2)meta.code;instr.telcharSimbadSimbad column added by the CDSmeta.ref.urlcharJ/AJ/146/10/notesNotesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBNameIVS source name (BHHMM+DDd)meta.id;meta.maincharNoteNotesmeta.note