VIII/108ivo://CDS.VizieR/VIII/108CDSPei Z-Y.Fan J.-H.Bastieri D.Yang J.-H.Xiao H.-B.2021-01-11T08:49:05Z2020-10-19T11:04:59ZCDS support team

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

cds-question@unistra.fractive-galactic-nucleiquasarsgamma-ray-astronomyWe present a sample of 4388 AGNs with available radio core-dominance parameters-defined as the ratio of the core flux densities to the extended ones, R=S_core_/S_ext._ - which includes 630 Fermi-detected AGNs from the fourth source catalog (4FGL) of the Fermi Large Area Telescope (Fermi/LAT); the rest are non-Fermi-detected AGNs. In our sample, 584 blazars are Fermi-detected and 1310 are not. The sample also contains other subclasses, such as Seyferts, Fanaroff-Riley I/II galaxies, and normal galaxies. We investigate various properties of the Fermi-detected and non-Fermi-detected AGNs by using core-dominance parameters, capitalizing on a previous study which showed that R is a good indicator of beaming. We then calculate radio spectral indices for the whole sample, and adopt {gamma}-ray-photon indices for the Fermi AGNs from the 4FGL catalog to discuss the properties of different subclasses. We obtain a relation between the core-dominance parameters and the radio spectral indices for both Fermi and non-Fermi sources, assuming a two-component model in the radio band. Our previous study ruled out the assumption that the core-dominance parameters and radio spectral indices are quite different for different AGN subclasses. This holds not only for Fermi sources but also for non-Fermi sources. In particular, R is, on average, greater for the former AGNs than for the latter. In this study, we enlarge our sample with available values of R to 4388 AGNs, and the obtained conclusions are consistent with our previous study. We assume that the same two-component model holds for the {gamma}-ray band as for the radio band, and therefore, adopt the same relation between the core-dominance parameters and the {gamma}-ray-photon indices for Fermi AGNs. Our fitting results indicate that the {gamma}-ray emissions of Fermi blazars originate mainly from the jet, and therefore, we conclude that the Fermi blazars are beamed.2020SCPMA..63y9511Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/VIII/108CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/ApJS/247/33 : The Fermi LAT fourth source catalog (4FGL) (Abdollahi+, 2020)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=VIII/108https://vizier.iucaa.in/viz-bin/VizieR-2?-source=VIII/108http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=VIII/108https://vizier.cds.unistra.fr/viz-bin/votable?-source=VIII/108https://vizier.iucaa.in/viz-bin/votable?-source=VIII/108http://vizieridia.saao.ac.za/viz-bin/votable?-source=VIII/108GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapGamma-rayRadiodefaultVIII/108/table1Fermi AGNsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordint4FGL4FGL name, 4FGL JHHMM.m+DDMMameta.id;meta.maincharNameIAU Namemeta.idcharClassClassification (G1)meta.code.classcharzRedshfitsrc.redshift;pos.heliocentricdoubleFluxFlux at 1GeV-100GeVcm**-2.s**-1phot.flux.density;em.gamma.harddoublealphag{gamma}-ray photon indexspect.index;em.line.HgammafloatlogRCore-dominance parameter compiled from r_logRphot.flux;arith.ratiofloatlogLg{gamma}-ray luminositylog(1e-07W)phys.luminosity;em.gammafloatalphaR? Radio spectral index (S_nu_{prop.to}nu^-alphaR^)spect.indexfloatnullabler_logRReference for logR (G2)meta.refcharVIII/108/table2non-Fermi AGNsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameIAU Namemeta.id;meta.maincharClassClassification (G1)meta.code.classcharzRedshfitsrc.redshift;pos.heliocentricdoublelogRCore-dominance parameter compiled from r_logRphot.flux;arith.ratiofloatalphaR? Radio spectral index (S_nu_{prop.to}nu^-alphaR^)spect.indexfloatnullabler_logRReference for logR (G2)meta.refchar