SUZAKUOBSERVATIONS OF γ-RAY BRIGHT RADIO GALAXIES: ORIGIN OF THE X-RAY EMISSION AND BROADBAND MODELING

AbstractObservations at high-energies are important to define the first stages of the evolution of extragalactic radio sources and to characterize the interstellar medium of their host galaxies. In some of the X-ray-observed Compact Symmetric Objects (CSOs, among the youngest and most compact radio galaxies), we measured values of the total hydrogen column densities large enough to slow or prevent the radio source growth. The γ-ray window has the potential to constrain the non-thermal contribution of jets and lobes to the total high-energy emission. However, so far, young radio sources remain elusive in γ-rays, with only a handful of detections (or candidates) reported by Fermi. I present our γ-ray study of the CSO PKS 1718–649, and draw comparison with the restarted, γ-ray detected, radio galaxy 3C 84.

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X-ray and γ-ray emissions from NLSy1 galaxies

International Journal of Modern Physics D ◽

10.1142/s0218271818440017 ◽

2018 ◽

Vol 27 (10) ◽

pp. 1844001 ◽

Cited By ~ 4

Author(s):

V. Baghmanyan ◽

N. Sahakyan

Keyword(s):

Spectral Properties ◽

Radio Galaxies ◽

Narrow Line ◽

High Luminosity ◽

Large Area ◽

X Ray ◽

Emission Properties ◽

Balmer Lines ◽

Γ Ray

The recent observations by Fermi large area telescope (Fermi-LAT) showed that in addition to the radio galaxies and blazars, Narrow-Line Seyfert 1 (NLSy1) galaxies are also [Formula: see text]-rays emitters. NLSy1 are AGNs with optical spectral properties similar to those of Seyfert 1 galaxies, except for having narrow Balmer lines and strong optical lines. They also exhibit strong X-ray variability, steep X-ray spectra and relatively high luminosity. The multiwavelength emission properties of 1H 0323+342, SBS 0846+513 and PMN J0948+0022 are discussed, using the [Formula: see text]-ray data from the last 8.8 years Fermi-LAT observations as well as available Swift(UVOT/XRT) data. It is shown that one-zone synchrotron/synchrotron self-Compton (SSC) model can satisfactorily reproduce their observed broadband spectra.

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Compton X-ray and γ-ray Emission from Extended Radio Galaxies

10.1063/1.2757334 ◽

2007 ◽

Cited By ~ 4

Author(s):

C. C. Cheung

Keyword(s):

Radio Galaxies ◽

X Ray ◽

Extended Radio ◽

Γ Ray

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Non-thermal emission in lobes of radio galaxies – III. 3C 98, Pictor A, DA 240, Cygnus A, 3C 326, and 3C 236

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz3415 ◽

2019 ◽

Vol 491 (4) ◽

pp. 5740-5746 ◽

Cited By ~ 2

Author(s):

Massimo Persic ◽

Yoel Rephaeli

Keyword(s):

Thermal Emission ◽

Radio Galaxies ◽

Spectral Energy ◽

Large Area ◽

Microwave Background ◽

Extragalactic Background Light ◽

X Ray ◽

Radiation Fields ◽

Cygnus A ◽

Γ Ray

ABSTRACT Recent analyses of the broad spectral energy distributions (SEDs) of extensive lobes of local radio galaxies have confirmed the leptonic origin of their Fermi/Large Area Telescope γ-ray emission, significantly constraining the level of hadronic contribution. SEDs of distant (DL > 125 Mpc) radio-galaxy lobes are currently limited to the radio and X-ray bands, hence give no information on the presence of non-thermal (NT) protons but are adequate to describe the properties of NT electrons. Modelling lobe radio and X-ray emission in 3C 98, Pictor A, DA 240, Cygnus A, 3C 326, and 3C 236, we fully determine the properties of intralobe NT electrons and estimate the level of the related γ-ray emission from Compton scattering of the electrons off the superposed cosmic microwave background, extragalactic background light, and source-specific radiation fields.

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