Application of the spine-layer jet radiation model to outbursts in the broad-line radio galaxy 3C 120

Abstract

We present a detailed Fermi/LAT data analysis for the broad-line radio galaxy 3C 120. This source has recently entered into a state of increased gamma-ray activity which manifested itself in two major flares detected by Fermi/LAT in September 2014 and April 2015 with no significant flux changes reported in other wavelengths. We analyse available data focusing our attention on aforementioned outbursts. We find very fast variability timescale during flares (of the order of hours) together with a significant gamma-ray flux increase. We show that the 6.8 years averaged gamma-ray emission of 3C 120 is likely a sum of the external radiation Compton and the synchrotron self-Compton radiative components. To address the problem of "orphan" gamma-ray flares and fast variability we model the jet radiation dividing the jet structure into two components: the wide and relatively slow outer layer and the fast, narrow spine. We show that with the addition of the fast spine occasionally bent towards the observer we are able to explain observed spectral energy distribution of 3C 120 during flares with the Compton up-scattered broad-line region and dusty torus photons as main gamma-rays emission mechanism.

12 pages, 8 figures, 2 tables

References in corpus (10)

• The Third Catalog of Active Galactic Nuclei Detected by the Fermi Large Area Telescope
• Doppler factors, Lorentz factors and viewing angles for quasars, BL Lacertae objects and radio galaxies
• GeV breaks in blazars as a result of gamma-ray absorption within the broad-line region
• The radio afterglow of Swift J1644+57 reveals a powerful jet with fast core and slow sheath
• Photometric reverberation mapping of 3C120
• The connection between the radio jet and the gamma-ray emission in the radio galaxy 3C 120
• Six Years of Fermi-LAT and Multi-wavelength Monitoring of the Broad-Line Radio Galaxy 3C 120: Jet Dissipation at Sub-parsec Scales from the Central Engine
• Broad-line region structure and kinematics in the radio galaxy 3C 120
• Magnetization of jets in luminous blazars
• Multi-wavelength Variability of the Broad Line Radio Galaxy 3C 120

Cited by in corpus (9)

• Fermi-LAT Observation of Non-Blazar AGNs
• Gamma-ray emission in radio galaxies under the VLBI scope -- I. Parsec-scale kinematics and high-energy properties of $\gamma$-ray detected TANAMI radio galaxies
• Comparing 3C 120 jet emission at small and large scales
• The Composition and Power of the Jet of the Broad-Line Radio Galaxy 3C 120
• Radio Galaxies with the Cherenkov Telescope Array
• Revisiting the TeV detection prospects for radio galaxies
• A search for $\gamma$-ray emission from a sample of local universe low-frequency selected radio galaxies
• Linking {\it Fermi} blazars and radio galaxies through accretion and jet radiation mechanisms
• A Ring of Fire Orphan γ-Ray Flare in the Neutrino Candidate 3C 120