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Related papers: Accretion Disk Coronae in High Luminosity Systems

200 papers

Compton scattering by a locally plane parallel atmosphere is analyzed within the Kompaneets approximation. In contrast to almost all previous analytic calculations of inverse Compton scattering, we assume neither homogeneity nor isotropy of…

Astrophysics · Physics 2009-10-31 Robert V. Wagoner , Alexander S. Silbergleit

A large fraction of accreting black hole and neutron stars systems present clear evidence of the reprocessing of X-rays in the atmosphere of an optically-thick accretion disk. The main hallmarks of X-ray reflection include fluorescent…

We test the disk/corona model of Janiuk et al. (2000) against the composite mean optical/UV/soft X-ray spectrum of radio loud and radio quiet quasars from Laor et al. (1997) which applies to faint quasars. The model well represents the…

Astrophysics · Physics 2007-05-23 Marek Nikolajuk , Bozena Czerny

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

Accretion onto supermassive black holes powers the most luminous persistent sources in the Universe, the so-called active galactic nuclei, whose emission is characterized by two distinct spectral components: thermal optical/ultraviolet…

We construct a disk-corona model which accounts for the optical-to-X-ray spectral properties of Seyfert nuclei and QSOs. We study emission spectrum emerging from a vertical disk-corona structure composed of two-temperature plasma by solving…

Astrophysics · Physics 2009-10-31 Toshihiro Kawaguchi , Toshiya Shimura , Shin Mineshige

We carry out a time dependent numerical simulation where both the hydrodynamics and the radiative transfer are coupled together. We consider a two-component accretion flow in which the Keplerian disk is immersed inside an accreting low…

High Energy Astrophysical Phenomena · Physics 2015-05-28 Himadri Ghosh , Sudip K. Garain , Kinsuk Giri , Sandip K. Chakrabarti

Galactic black hole (BH) X-ray binaries are known to exhibit episodic outbursts, during which accretion and spectral mode distinctively transition between low/hard and high/soft state. X-ray observations during high/soft state occasionally…

High Energy Astrophysical Phenomena · Physics 2025-02-25 Keigo Fukumura

We solve for the structure of a hot accretion disc with unsaturated thermal Comptonisation of soft photons and with advection, generalizing the classical model of Shapiro et al. The upper limit on the accretion rate due to advection…

Astrophysics · Physics 2015-06-24 Andrzej A. Zdziarski

We present a model for a corona above a geometrically thin standard disk around a black hole. This corona is fed by matter from the thin disk which evaporates from the cool layers underneath. An equilibrium establishes between the cool…

Astrophysics · Physics 2007-05-23 Friedrich Meyer , Bifang Liu , Emmi Meyer-Hofmeister

We apply our self-consistent accretion disk corona (ADC) model, with two different geometries, to the broad-band X-ray spectrum of the black hole candidate Cygnus X-1. As shown in a companion paper (Dove, Wilms, and Begelman), models where…

Astrophysics · Physics 2009-10-30 James B. Dove , Jorn Wilms , Michael Maisack , Mitchell C. Begelman

We summarize results from a survey of radiation-dominated black hole accretion flows across a wide range of mass accretion rates, as well as two values of black hole spin and initial magnetic field geometry. These models apply an algorithm…

High Energy Astrophysical Phenomena · Physics 2025-09-16 Lizhong Zhang , James M. Stone , Patrick D. Mullen , Shane W. Davis , Yan-Fei Jiang , Christopher J. White

The disk-corona evaporation model naturally interprets many observational phenomena in black hole X-ray binaries, such as the truncation of an accretion disk and the spectral state transitions. On the other hand, magnetic field is known to…

Astrophysics · Physics 2009-11-13 Lei Qian , B. F. Liu , Xue-Bing Wu

Models of X-ray production in black-hole sources are reviewed and compared with recent observations. Possible diagnostics of the hot-disk and disk-corona models are discussed in the light of spectral and temporal data. A new model of a…

Astrophysics · Physics 2009-11-06 Andrei M. Beloborodov

We study the effects of thermal conduction in a hot, active corona above an accretion disk. We assume that all of the dissipative heating takes place in the corona. We find that the importance of conduction decreases with increases in the…

Astrophysics · Physics 2009-10-30 Andrzej Maciolek-Niedzwiecki , Julian H. Krolik , Andrzej A. Zdziarski

Several galactic black holes show transitions between spectral states. In this paper we present a unifying radiation transfer model that can fit the spectral data in both states. We fit individual broad-band (from 1 keV up to 4 MeV)…

Astrophysics · Physics 2007-05-23 Juri Poutanen , Paolo Coppi

We apply a model of magnetically dominated coronae above standard accretion discs to the low/hard state of galactic black holes. When the disc-corona coupling is accounted for self-consistently assuming that magneto-rotational instability…

Astrophysics · Physics 2007-05-23 A. Merloni

IPCVs contain a magnetic, rotating white dwarf surrounded by a magnetically truncated accretion disk. To explain their strong flickering X-ray emission, accretion has been successfully taken into account. Nevertheless, observations suggest…

Solar and Stellar Astrophysics · Physics 2017-04-12 Enrico Barbera , Salvatore Orlando , Giovanni Peres

The disk corona evaporation model extensively developed for the interpretation of observational features of black hole X-ray binaries (BHXRBs) is applied to AGNs. Since the evaporation of gas in the disk can lead to its truncation for…

High Energy Astrophysical Phenomena · Physics 2014-11-20 B. F. Liu , Ronald E. Taam

The models that seek to explain the reflection spectrum in black hole binaries usually invoke a point-like primary source of hard X-rays. This source illuminates the accretion disk and gives rise to the discrete (lines) and…

High Energy Astrophysical Phenomena · Physics 2021-02-17 P. Reig , N. D. Kylafis
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