J/ApJ/808/162ivo://CDS.VizieR/J/ApJ/808/162doi:10.26093/cds/vizier.18080162CDSCasadio C.Gomez J.L.Grandi P.Jorstad S.G.Marscher A.P.,Lister M.L.Kovalev YU.Y.Savolainen T.Pushkarev A.B.2017-07-11T13:08:35Z2015-12-21T12:17:37ZCDS support team

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

cds-question@unistra.frradio-galaxiesactive-galactic-nucleiradio-continuum-emissiongamma-ray-astronomyWe present the analysis of the radio jet evolution of the radio galaxy 3C 120 during a period of prolonged {gamma}-ray activity detected by the Fermi satellite between 2012 December and 2014 October. We find a clear connection between the {gamma}-ray and radio emission, such that every period of {gamma}-ray activity is accompanied by the flaring of the millimeter very long baseline interferometry (VLBI) core and subsequent ejection of a new superluminal component. However, not all ejections of components are associated with {gamma}-ray events detectable by Fermi. Clear {gamma}-ray detections are obtained only when components are moving in a direction closer to our line of sight. This suggests that the observed {gamma}-ray emission depends not only on the interaction of moving components with the millimeter VLBI core, but also on their orientation with respect to the observer. Timing of the {gamma}-ray detections and ejection of superluminal components locate the {gamma}-ray production to within ~0.13pc from the millimeter VLBI core, which was previously estimated to lie about 0.24pc from the central black hole. This corresponds to about twice the estimated extension of the broad line region, limiting the external photon field and therefore suggesting synchrotron self Compton as the most probable mechanism for the production of the {gamma}-ray emission. Alternatively, the interaction of components with the jet sheath can provide the necessary photon field to produced the observed {gamma}-rays by Compton scattering.2015ApJ...808..162Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/808/162CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/ApJ/798/134 : MOJAVE. XII. Acceleration of blazar jets (Homan+, 2015)J/AJ/146/120 : MOJAVE. X. Parsec-scale kinematics of AGNs (Lister+, 2013)J/MNRAS/430/60 : Suzaku view of highly ionized outflows in AGN (Gofford+, 2013)J/A+A/544/A18 : Radio galaxies of the local universe (van Velzen+, 2012)J/ApJ/754/23 : Blazar submm + {gamma}-ray luminosities (Leon-Tavares+, 2012)J/ApJS/199/31 : Fermi LAT second source catalog (2FGL) (Nolan+, 2012)J/ApJS/194/29 : Observations of blazars at 15GHz (Richards+, 2011)J/ApJ/743/171 : The 2LAC catalog (Ackermann+, 2011)J/ApJ/742/27 : 15GHz and jet properties of MOJAVE blazars (Lister+, 2011)J/ApJ/734/43 : X-ray, optical & radio monitoring of 3C111 (Chatterjee+, 2011)J/ApJ/706/1253 : MOJAVE VII. Blazar jet acceleration (Homan+, 2009)J/AJ/138/1874 : MOJAVE. VI. Kinematic analysis of blazar jets (Lister+, 2009)J/AJ/137/3718 : 15GHz monitoring of AGN jets with VLBA (Lister+, 2009)J/PAZh/35/403 : Optical Variabilities in 3C 120 (Doroshenko+, 2009)J/other/ChJAA/8.385 : Superluminal motion in AGN (Zhang+, 2008)J/AJ/134/799 : Multiwaveband polarimetry of 15 AGN (Jorstad+, 2007)J/AJ/130/1418 : AGN jet kinematics (Jorstad+, 2005)J/A+AS/122/271 : mm-monitoring of radio sources IV. (Reuter+ 1997)J/ApJS/51/67 : 5 GHz Observations of Arecibo 611 MHz Sources (Lawrence+ 1983)http://www.physics.purdue.edu/MOJAVE : MOJAVE home pagehttp://www.bu.edu/blazars/research.html : BU blazar group home pagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/808/162https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/808/162http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/808/162https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/808/162https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/808/162http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/808/162GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapRadioGamma-raydefaultJ/ApJ/808/162/vlbaVLBA 15GHz and 43GHz model-fit components' parametersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintObs.YDecimal year of the observationyrtime.epoch;obsfloatMJDModified Julian Date of the observationdtime.epochdoubleNameComponent identifiermeta.id.partcharBandBandGHzinstr.bandpasscharFlux[0.08/1489] Observed flux densitymJyphot.flux.density;em.radio.12-30GHzfloate_Flux[1/74] Uncertainty in FluxmJystat.error;phot.fluxintD[0.07/17]? Distance from the C0 componentmaspos.angDistancefloatnullablee_D[0.01/2]? Uncertainty in Dmasstat.errorfloatnullablePA[-131/-95]? Position angledegpos.posAngfloatnullablee_PA[0.6/29]? Uncertainty in PAdegstat.errorfloatnullablel_FWHMLimit flag on FWHMmeta.code.error;phys.angSizecharFWHM[0.03/4] Component Full-Width at Half-Maximummasphys.angSizefloate_FWHM[0.01/4]? Uncertainty in FWHMmasstat.error;phys.angSizefloatnullable