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Related papers: Gamma-ray observations of low-luminosity active ga…

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Aims. We use a sample of 83 core-dominated active galactic nuclei (AGN) selected from the MOJAVE (Monitoring of Jets in AGN with VLBA Experiments) radio-flux-limited sample and detected with the Fermi Large Area Telescope (LAT) to study the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 T. G. Arshakian , J. León-Tavares , M. Boettcher , J. Torrealba , V. H. Chavushyan , M. L. Lister , E. Ros , J. A. Zensus

I give a brief review of the observational properties of low-luminosity AGNs (LLAGNs). I outline some unresolved issues in the study of LLAGNs, emphasizing the uncertainties in the role of the truncated thin accretion disk, the dusty…

High Energy Astrophysical Phenomena · Physics 2013-02-05 Rodrigo Nemmen

A number of radio galaxies has been detected by Fermi/LAT in the gamma-ray domain. In some cases, like Cen A and M 87, these objects have been seen even in the TeV range by Cherenkov telescopes. Whereas the gamma-ray emission is likely to…

High Energy Astrophysical Phenomena · Physics 2013-02-20 V. Beckmann , S. de Jong , F. Mattana , D. Saez , S. Soldi

The radio-X-ray slope in the fundamental plane of radio-loud active galactic nuclei (AGNs) is found to be steeper compared with that of radio-quiet AGNs in previous works. In this work, we reinvestigate the fundamental plane in radio-loud…

Astrophysics of Galaxies · Physics 2018-09-12 Shuang-Liang Li , Minfeng Gu

We present ASCA X-ray results on two S0 galaxies, NGC 3065 and NGC 4203. In both galaxies, we detected hard X-ray emission from a point-like source at the nucleus. Single power law model having a photon index of 1.8 well described the…

We present 5 GHz e-MERLIN radio images at 50 mas resolution of the nuclear regions of the Legacy e-MERLIN Multi-band Imaging of Nearby Galaxies survey (LeMMINGs), the deepest statistically complete radio-band survey of the local Universe…

The Fermi-LAT satellite has recently discovered a small group of radio galaxies and steep spectrum radio sources: the misaligned AGNs (MAGNs) sample. We present the X-ray analysis of all the sources of this sample (7 FRIs and 3 FRIIs) with…

High Energy Astrophysical Phenomena · Physics 2012-05-09 Eleonora Torresi

We perform an exploratory study of the physical properties of accretion flows and jets in low-luminosity active galactic nuclei (LLAGNs) by modeling the spectral energy distributions (SEDs) of 12 LLAGNs in low-ionization nuclear…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Rodrigo S. Nemmen , Thaisa Storchi-Bergmann , Michael Eracleous

The Gamma-ray detection from an astrophysical object indicates the presence of an extreme environment where high-energy radiation is produced. With the continuous monitoring of the Gamma-ray sky by the Fermi Large Area Telescope (LAT),…

High Energy Astrophysical Phenomena · Physics 2024-12-18 Subhashree Swain , Vaidehi S. Paliya , D. J. Saikia , C. S. Stalin

Relativistic jets are one of the most powerful manifestations of the release of energy produced around supermassive black holes at the centre of active galactic nuclei (AGN). Their emission is observed across the entire electromagnetic…

High Energy Astrophysical Phenomena · Physics 2015-06-17 M. Orienti , F. D'Ammando , M. Giroletti , D. Dallacasa , T. Venturi , G. Giovannini

Radio galaxies are uncommon $\gamma$-ray emitters, and only low redshift radio galaxies are detected with Fermi-LAT. However, they offer potential insights into the emission mechanisms of active galaxies, particularly as the alignment of…

High Energy Astrophysical Phenomena · Physics 2020-06-17 Max Harvey , Cameron B. Rulten , Paula M. Chadwick

We report on XMM-Newton spectroscopy of the low-luminosity active galaxies (LLAGN) M81 and NGC4579 both of which have known black hole masses and well-sampled spectral energy distributions (SED). The iron Kalpha line profiles from both the…

Astrophysics · Physics 2009-11-10 G. C. Dewangan , R. E. Griffiths , T. Di Matteo , N. J. Schurch

We present a statistical characterization of the $\gamma$-ray emission from the four \emph{Fermi}-LAT sources: FR I radio galaxy NGC 1275, BL Lac Mrk 421, FSRQs B2 1520+31 and PKS 1510-089 detected almost continuously over a time…

High Energy Astrophysical Phenomena · Physics 2017-11-09 Pankaj Kushwaha , Atreyee Sinha , Ranjeev Misra , K. P. Singh , E. M. de Gouveia Dal Pino

We report the discovery with Fermi/LAT of gamma-ray emission from three radio-loud narrow-line Seyfert 1 galaxies: PKS 1502+036 (z=0.409), 1H 0323+342 (z=0.061) and PKS 2004-447 (z=0.24). In addition to PMN J0948+0022 (z=0.585), the first…

High Energy Astrophysical Phenomena · Physics 2011-02-11 LAT Collaboration , G. Ghisellini , L. Maraschi , F. Tavecchio

We present deep Near-infrared (NIR) images of a sample of 19 intermediate-redshift ($0.3<z<1.0$) radio-loud active galactic nuclei (AGN) with powerful relativistic jets ($L_{1.4GHz} >10^{27}$ WHz$^{-1}$), previously classified as…

Narrow-line Seyfert 1 (NLS1) galaxies provide us with unique insights into the drivers of AGN activity under extreme conditions. Given their low black hole (BH) masses and near-Eddington accretion rates, they represent a class of galaxies…

High Energy Astrophysical Phenomena · Physics 2017-06-28 V. Karamanavis , E. Angelakis , S. Komossa , I. Myserlis , D. Blinov , J. A. Zensus

Gamma-ray Astronomy studies cosmic accelerators through their electromagnetic radiation in the energy range between ~100 MeV and ~100 TeV. The present most sensitive observations in this energy band are performed, from space, by the Large…

High Energy Astrophysical Phenomena · Physics 2011-11-29 Javier Rico

They are weak, they are small, and they are often overlooked, but they are numerous and an ubiquitous sign of accreting black holes: compact radio cores and jets in low-power AGN. Here I summarize our work concerning these radio cores and…

Astrophysics · Physics 2007-05-23 Heino Falcke

We evaluate the contribution to the Isotropic Gamma-Ray Background (IGRB) coming from Radio Galaxies (RGs), the subclass of radio-loud Active Galactic Nuclei (AGN) with the highest misalignment from the line of sight (l.o.s.). Since only a…

High Energy Astrophysical Phenomena · Physics 2025-10-08 A. Circiello , A. McDaniel , M. Di Mauro , C. Karwin , N. Khatiya , M. Ajello , F. Donato , D. Hartmann , A. Strong

A wide-frequency radio study of Active Galactic Nuclei (AGN) is crucial to evaluate the intervening radiative mechanisms responsible for the observed emission and relate them with the underlying accretion physics. We present wide frequency…