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Related papers: AGN Coronal Emission models I. The Predicted Radio…

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The dichotomy between radio-loud (RL) and radio-quiet (RQ) active galactic nuclei (AGN) is thought to be intrinsically related to radio jet production. This difference may be explained by the presence of a strong magnetic field (B-field)…

Unraveling the origins of radio emissions from radio-quiet active galactic nuclei (RQ AGNs) remains a pivotal challenge in astrophysics. One potential source of this radiation is the shock interaction between AGN disk winds and the…

High Energy Astrophysical Phenomena · Physics 2024-04-09 Tomoya Yamada , Nobuyuki Sakai , Yoshiyuki Inoue , Tomonari Michiyama

Accretion disk coronae are believed to account for X-ray emission in Active Galactic Nuclei (AGNs). In this paper the observed emission is assumed to be due to a population of relativistic, non-thermal electrons (e.g. produced in a flare)…

Astrophysics · Physics 2009-11-10 G. Torricelli , P. Pietrini , A. Orr

The origin of core radio emission in radio-quiet active galactic nuclei (AGNs) is still actively debated. General relativistic magnetohydrodynamics simulations often predict the launching of moderately large-scale jets from super-Eddington…

High Energy Astrophysical Phenomena · Physics 2026-01-13 Jeremiah D. Paul , Richard M. Plotkin

The launch of the Infrared Space Observatory and new atomic data have opened a window to the study of high ionization gas in active galactic nuclei (AGN). We present the results of a large number of photoionization simulations of the…

Astrophysics · Physics 2009-10-30 Jason W. Ferguson , Kirk T. Korista , Gary J. Ferland

The X-ray spectra of active galactic nuclei (AGNs) often exhibit an excess of emission above the primary power-law at energies <~ $2$ keV. Two models for the origin of this `soft excess' are ionized relativistic reflection from the inner…

High Energy Astrophysical Phenomena · Physics 2022-06-22 Xin Xiang , D. R. Ballantyne , S. Bianchi , A. De Rosa , G. Matt , R. Middei , P. -O. Petrucci , A. Rozanska , F. Ursini

[abridged] 1H 0419-577 is a highly-accreting, luminous BLS1 AGN. This study aims to characterise its disc-corona system using, for the first time, simultaneous XMM-Newton and NuSTAR observations, performed in May and November 2018. We…

High Energy Astrophysical Phenomena · Physics 2025-08-13 Delphine Porquet , James N. Reeves , Valentina Braito

To explain X-ray spectra of active galactic nuclei (AGN), non-thermal activity in AGN coronae such as pair cascade models has been extensively discussed in the past literature. Although X-ray and gamma-ray observations in the 1990s…

High Energy Astrophysical Phenomena · Physics 2021-05-20 Yoshiyuki Inoue , Dmitry Khangulyan , Akihiro Doi

Three-dimensional hydrodynamic simulations, covering the spatial domain from hundreds of Schwarzschild radii to $2\ \mathrm{pc}$ around the central supermassive black hole of mass $10^8 M_\odot$, with detailed radiative cooling processes,…

Astrophysics of Galaxies · Physics 2016-02-03 Lile Wang , Renyue Cen

The origin of compact millimeter (mm) continuum emission from radio-quiet AGNs (RQAGNs) is still not fully understood. Changing-state AGNs (CSAGNs) display rapid and strong variability, which can allow us to investigate the origin of the mm…

Broadband X-ray spectroscopy of the X-ray emission produced in the coronae of active galactic nuclei (AGN) can provide important insights into the physical conditions very close to their central supermassive black holes. The temperature of…

Non-jetted AGN exhibit hard X-ray emission with a power law spectrum above $\sim$2 keV, which is thought to be produced through Comptonization of soft photons by electrons and positrons (pairs) in the vicinity of the black hole. The origin…

High Energy Astrophysical Phenomena · Physics 2026-05-13 Despina Karavola , Maria Petropoulou , Damiano F. G. Fiorillo , Luca Comisso , Lorenzo Sironi

A long-standing question in active galactic nucleus (AGN) research is how the corona is heated up to produce X-ray radiation much stronger than that arising from the viscous heating within the corona. In this paper, we carry out detailed…

High Energy Astrophysical Phenomena · Physics 2020-06-05 Huaqing Cheng , B. F. Liu , Jieying Liu , Zhu Liu , Erlin Qiao , Weimin Yuan

The soft excess is a significant emission component in the Soft (<1 keV) X-ray spectra of many AGN. It has been explained by disk reflection, a warm corona and other models. Understanding its origin is crucial for the energy budget of AGN…

High Energy Astrophysical Phenomena · Physics 2023-09-20 A. Zoghbi , J. M. Miller

The corona is a key component of most luminous accreting black holes, carrying 5 - 30 % of the power and in non-jetted Active Galactic Nuclei (AGN), creating all the X-ray emission above $\simeq 1-2$ keV. Its emission illuminates the inner…

High Energy Astrophysical Phenomena · Physics 2019-03-14 Nikita Kamraj , Andrew Fabian , Anne Lohfink , Mislav Baloković , Claudio Ricci , Kristin Madsen

The soft excess in active galactic nuclei (AGNs) may arise through a combination of relativistic reflection and the effects of a warm corona at the surface of the accretion disc. Detailed examination of the soft excess can therefore…

High Energy Astrophysical Phenomena · Physics 2024-04-05 D. R. Ballantyne , V. Sudhakar , D. Fairfax , S. Bianchi , B. Czerny , A. De Rosa , B. De Marco , R. Middei , B. Palit , P. -O. Petrucci , A. Rozanska , F. Ursini

Active Galactic Nuclei (AGN) host accreting supermassive black holes (SMBHs). The accretion can lead to the formation of a hot, X-ray emitting corona close to the SMBH capable of accelerating relativistic electrons. Observations in the…

We study vertical structure of radiation pressure dominated disc with a hot corona. We include all the relevant processes like bound--free opacity and convection. We show that the presence of the corona modifies considerably the density and…

Astrophysics · Physics 2015-06-24 A. Różańska , B. Czerny , P. T. Życki , G. Pojmański

It is commonly believed that the optical/UV and X-ray emissions in luminous AGN are produced in an accretion disk and an embedded hot corona respectively. The inverse Compton scattering of disk photons by hot electrons in the corona can…

High Energy Astrophysical Phenomena · Physics 2015-05-05 B. F. Liu , R. E. Taam , E. Qiao , W. Yuan

We predict the observational signatures of galaxy scale outflows powered by active galactic nuclei (AGN). Most of the emission is produced by the forward shock driven into the ambient interstellar medium (ISM) rather than by the reverse…

Astrophysics of Galaxies · Physics 2015-06-22 Jesse Nims , Eliot Quataert , Claude-Andre Faucher-Giguere