J/MNRAS/357/1267ivo://CDS.VizieR/J/MNRAS/357/1267doi:10.26093/cds/vizier.73571267CDSCirasuolo M.Magliocchetti M.Celotti A.2024-06-30T20:17:06Z2006-06-04T23:10:19ZCDS support team

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

cds-question@unistra.frquasarsradio-sourcesphotometryredshiftedThe quasar sample selected by cross-correlating the Faint Images of the Radio Sky at Twenty cm (FIRST, <VIII/71>) survey and the 2-degree Field Quasar Redshift Survey (2QZ, <VII/223>) allows us to explore, for the first time, the faint end of the radio and optical luminosity functions up to z=~2.2. We find indications (~3{sigma}) of a negative evolution for these faint sources at z>~1.8, both in radio and optical bands. This corresponds to a decrement in the space density of faint quasars of approximately a factor 2 at z=2.2 and confirms the presence of a differential evolution for the population of radio-active quasars. The faint end of both luminosity functions flattens and the comparison with the (optical) number density of the whole quasar population supports a dependence of the fraction of radio-detected quasars on the optical luminosity. A progressive decrease in the fraction of quasars in the whole radio source population can be consistently accounted for within the receding torus scenario. The population of low-luminosity quasars, which the FIRST-2dF detects, appears to depart from the classical scheme for radio-loud quasars.2005MNRAS.357.1267Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/357/1267CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/MNRAS/341/993 : u_j_br photometry and redshifts of QSOs (Cirasuolo+, 2003)VII/223 : The 2dF QSO Redshift Survey. V. The 10k cat. (Croom+ 2001)VII/241 : The 2dF QSO Redshift Survey (Croom+ 2004)VIII/71 : The FIRST Survey Catalog, Version 03Apr11 (Becker+ 2003)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/357/1267https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/357/1267http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/357/1267https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/357/1267https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/357/1267http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/357/1267GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/357/1267/table1 (Optical and radio properties of the FIRST-2QZ quasar sample (not included in Cirasuolo et al. 2003, Cat. <J/MNRAS/341/993>))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/357/1267/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/357/1267/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/357/1267/table1?GETtext/xml+votable180.050000true151.7680833-2.11969440.0055555555555555565/6507 6552 6555 6/25591 25593-25594 25596 25843-25846 25852-25853 25887 25903 25912 25918 25923 25931-25932 25935 25938-25939 25942 25947-25948 25950 25952-25953 25955-25956 25960 25962-25964 25996 25999-26001 26006 26020 26025-26027 26035-26036 26038 26042 26049 26159 26165 26170 26175 26179 26181-26182 26184 26186-26190 26192 26194-26196 26206 26212 26215-26217 26224-26226 26232 26243-26244 26250 26258 26261-26262 26266-26270 26277-26279 26283-26284 26286 26289-26290 26296 26305-26306 26308 26372 26377 26863 26874-26875 26878 26931 26933 26935-26936 26940 26947 26950-26951 26953-26954 26956-26958 26960 26962 26966 26968 26974-26975 26978-26980 26983 26990 26993-26995 27000 27021-27022 27027-27030 27034 27037 27039 27041-27042 27046 27051-27052 27055-27056 27058-27061 27072-27074 27080 27206 27212 27217-27220 27222 27226 27230 27251 27392 27394 27398 27400 27648 27651 27656https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/357/1267?format=asciiOpticalRadiodefaultJ/MNRAS/357/1267/table1Optical and radio properties of the FIRST-2QZ quasar sample (not included in Cirasuolo et al. 2003, Cat. <J/MNRAS/341/993>)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainbjmagb_j_ magnitudemagphot.mag;em.opt.Bfloatu-bju-b_j_ colour indexmagphot.color;em.opt.U;em.opt.Bfloatbj-rb_j_-r colour indexmagphot.color;em.opt.B;em.opt.RfloatS1.4GHzRadio-flux density at 1.4GHzmJyphot.flux.density;em.radio.750-1500MHzdoublezRedshiftsrc.redshiftfloatMorph[dtm] Radio morphological appearance (1)meta.code;src.morphcharalphaR? Radio spectral indexspect.indexfloatnullable2dF2dF name (JHHMMSS.s+DDMMSS)meta.id;meta.mainchar