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Related papers: Accretion Disks in AGNs

200 papers

Taking optically thin accretion flows as an example, we investigate the dynamics and the emergent spectra of accretion flows with different outer boundary conditions (OBCs) and find that OBC plays an important role in accretion disk model.…

Astrophysics · Physics 2016-01-27 Feng Yuan

The accretion disks that fuel active galactic nuclei (AGN) may house numerous stars and compact objects, formed in situ or captured from nearby star clusters. Embedded neutron stars and black holes may form binaries and eventually merge,…

High Energy Astrophysical Phenomena · Physics 2023-10-31 Alexander J. Dittmann , Adam M. Dempsey , Hui Li

We calculate the structure of accretion disk around a spinning black hole for accretion rates 0.01 - 10 M_sun/s. The model is fully relativistic and treats accurately the disk microphysics including neutrino emissivity, opacity, electron…

Astrophysics · Physics 2011-04-11 Wen-xin Chen , Andrei M. Beloborodov

We compile a sample of 92 active galactic nuclei (AGNs) at z<0.75 with $gri$ photometric light curves from the archival data of the Zwicky Transient Facility and measure the accretion disk sizes via continuum reverberation mapping. We…

Astrophysics of Galaxies · Physics 2022-04-20 Wei-Jian Guo , Yan-Rong Li , Zhi-Xiang Zhang , Luis C. Ho , Jian-Min Wang

Relativistic jets can be produced within the accretion disk of an active galactic nucleus (AGN), leading to distinct thermal emission as they propagate through a dense disk environment. In this paper, we present a comprehensive study of…

High Energy Astrophysical Phenomena · Physics 2026-05-26 Ken Chen , Zi-Gao Dai

Recent advances in our understanding of massive star formation have made clear the important role of protostellar disks in mediating accretion. Here we describe a simple, semi-analytic model for young, deeply embedded, massive accretion…

Astrophysics · Physics 2007-12-07 Kaitlin M. Kratter , Christopher D. Matzner , Mark. R. Krumholz

We review the current status of studies on accretion and protoplanetary disks of young stars with large-scale magnetic fields. Observational data on magnetic fields of the disks are compiled and analysed. Modern analytical and numerical MHD…

Solar and Stellar Astrophysics · Physics 2024-01-26 Sergey A. Khaibrakhmanov

Luminous active galactic nuclei (AGN) and X-Ray binaries (XRBs) often contain geometrically thin, radiatively cooled accretion discs. According to theory, these are -- in many cases -- initially highly misaligned with the black hole…

High Energy Astrophysical Phenomena · Physics 2022-08-11 M. Liska , C. Hesp , A. Tchekhovskoy , A. Ingram , M. van der Klis , S. B. Markoff , M. Van Moer

An accretion flow onto a supermassive black hole is the primary process powering quasars. However, a geometry of this flow is not well constrained. Both global MHD simulations and observations suggest that there are several emission…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-08 Aneta Siemiginowska

Accretion flows toward black holes can be of a quite different nature, described as an optically thick cool gas flow in a disk for high accretion rates or as a hot coronal optically thin gas flow for low accretion rates, possibly affected…

High Energy Astrophysical Phenomena · Physics 2017-12-13 E. Meyer-Hofmeister , B. F. Liu , E. Qiao

Using three-dimensional general relativistic magnetohydrodynamic simulations with electron and proton thermodynamics and an electron cooling function, we probe the inner radial and vertical structure of weakly magnetized geometrically thin…

High Energy Astrophysical Phenomena · Physics 2025-08-28 A. Hankla , J. Dexter , N. Scepi

Accretion discs properties should deviate from standard theory when magnetic pressure exceeds the thermal pressure. To quantify these deviations, we present a systematic study of the dynamical properties of magnetically arrested discs…

High Energy Astrophysical Phenomena · Physics 2023-10-26 Nicolas Scepi , Mitchell C. Begelman , Jason Dexter

X-ray spectroscopy offers an opportunity to study the complex mixture of emitting and absorbing components in the circumnuclear regions of active galactic nuclei, and to learn about the accretion process that fuels AGN and the feedback of…

High Energy Astrophysical Phenomena · Physics 2009-11-13 T. J. Turner , L. Miller

We review some recent results of general relativistic magnetohydrodynamic (GR-MHD) simulations considering the evolution of geometrically thin disks around a central black hole. Thin disk GR-MHD simulations complement the widely used MAD…

High Energy Astrophysical Phenomena · Physics 2024-04-10 Indu K. Dihingia , Christian Fendt

I outline the theory of accretion onto black holes, and its application to observed phenomena such as X-ray binaries, active galactic nuclei, tidal disruption events, and gamma-ray bursts. The dynamics as well as radiative signatures of…

High Energy Astrophysical Phenomena · Physics 2014-10-31 Mitchell C. Begelman

We consider effects of the MHD turbulence on the viscosity during the evolution of the thermal-viscous ionization instability in the standard $\alpha$-accretion disks. We consider the possibility that the accretion onto a supermassive black…

Astrophysics · Physics 2009-11-10 Agnieszka Janiuk , Bozena Czerny , Aneta Siemiginowska , Ryszard Szczerba

I review recent progresses in the dynamics and the evolution of self-gravitating accretion discs. Accretion discs are a fundamental component of several astrophysical systems on very diverse scales, and can be found around supermassive…

Astrophysics · Physics 2009-11-13 G. Lodato

We present a comprehensive analysis of four near-Eddington black hole accretion models computed by solving the GRMHD equations with full radiation transport. This study focuses on the dynamical effects of magnetic field topology and black…

High Energy Astrophysical Phenomena · Physics 2026-03-09 Lizhong Zhang , James M. Stone , Shane W. Davis , Yan-Fei Jiang , Patrick D. Mullen , Christopher J. White

An approximate analytic one-dimensional model is constructed, for the accretion disk boundary layer surrounding a neutron star whose low magnetic field does not affect the process of accretion. A high luminosity model is considered, with…

High Energy Astrophysical Phenomena · Physics 2025-11-25 G. S. Bisnovatyi-Kogan

We discuss the results of three-dimensional magnetohydrodynamic simulations, using a pseudo-Newtonian potential, of thin disk (h/r ~ 0.1) accretion onto black holes. We find (i) that magnetic stresses persist within the marginally stable…

Astrophysics · Physics 2009-11-06 Christopher S. Reynolds , Philip J. Armitage , James Chiang