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Related papers: HOT ACCRETION DISKS WITH ADVECTION

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We consider the effects of advection and radial gradients of pressure and radial drift velocity on the structure of optically thick accretion disks. We concentrate our efforts on highly viscous disks, $\alpha=1.0$, with large accretion…

Astrophysics · Physics 2007-05-23 I. V. Artemova , G. S. Bisnovatyi-Kogan , G. Bjoernsson , I. D. Novikov

We consider the effects of advection and radial gradients of pressure and radial drift velocity on the structure of accretion disks around black holes with proper description of optically thick/thin transitions. We concentrated our efforts…

Astrophysics · Physics 2009-11-10 Yu. V. Artemova , G. S. Bisnovatyi-Kogan , I. V. Igumenshchev , I. D. Novikov

We present solutions to the accretion disk structure equations in which advective cooling is accounted for in a self-consistent way. It is shown that for high rates of accretion, above a critical value, when without advection there are no…

Astrophysics · Physics 2007-05-23 I. V. Artemova , G. S. Bisnovatyi-Kogan , G. Bjornsson , I. Novikov

We show that most of hot, optically thin accretion disk models which ignore advective cooling are not self-consistent. We have found new types of optically thin disk solutions where cooling is dominated by radial advection of heat. These…

Astrophysics · Physics 2009-10-22 Marek A. Abramowicz , Xingming Chen , Shoji Kato , Jean-Pierre Lasota , Oded Regev

By taking into account the local energy balance per unit volume between the viscous heating and the advective cooling plus the radiative cooling, we investigate the vertical structure of radiation pressure-supported accretion disks in…

High Energy Astrophysical Phenomena · Physics 2012-07-31 Wei-Min Gu

Cold optically thick accretion disks with hot coronae and radial advection have been investigated. Within the framework of $\alpha$-viscosity models, we assume that all the mass accretion and angular momentum transport take place in the…

Astrophysics · Physics 2009-10-28 Xingming Chen

We explore the thermodynamic and global structural properties of a local patch of an accretion disk whose parameters were chosen so that radiation pressure and gas pressure would be comparable in magnitude. Heating, radiative transport, and…

Astrophysics · Physics 2009-06-23 Julian H. Krolik , Shigenobu Hirose , Omer Blaes

The effect of a possible hydrodynamical wind on the nature of hot accretion disk solutions is studied. It is found that the advection dominated branch, in the presence of a wind, maintains the self-similar solution for the disk structure…

Astrophysics · Physics 2009-11-06 Ranjeev Misra , Ronald E. Taam

We present here the solution for accretion disk structure, which describes continuously the transition between optically thick and optically thin disk regions. We show that the disk structure equations without advection, used here, give two…

Astrophysics · Physics 2007-05-23 I. V. Artemova , G. S. Bisnovatiy-Kogan , G. Bjornsson , I. D. Novikov

We consider non-local effects which arise when radiation emitted at one radius of an accretion disk either heats or cools gas at other radii through Compton scattering. We discuss three situations: 1. Radiation from the inner regions of an…

Astrophysics · Physics 2016-08-30 Ann A. Esin

Standard accretion disk theory is formulated which is based on the local heat balance. The energy produced by a turbulent viscous heating is supposed to be emitted to the sides of the disc. Sources of turbulence in the accretion disc are…

Astrophysics · Physics 2007-05-23 G. S. Bisnovatyi-Kogan

Advection is believed to be the dominant cooling mechanism in optically thin advection-dominated accretion flows (ADAF's). When outflow is considered, however, the first impression is that advection should be of opposite sign in the inflow…

High Energy Astrophysical Phenomena · Physics 2023-01-24 Cheng-Liang Jiao

The effects of radial advection and thermal diffusion were considered in investigating the linear stability of an optically thin, two-temperature accretion disc. If the disc has only very little advection, we proved that the thermal…

Astrophysics · Physics 2015-06-24 Xue-Bing Wu

We present global solutions of optically thin, two-temperature black hole accretion disks incorporating magnetic fields. We assume that the {\pi}{\phi}-component of the Maxwell stress is proportional to the total pressure, and prescribe the…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Hiroshi Oda , Mami Machida , Kenji E. Nakamura , Ryoji Matsumoto , Ramesh Narayan

We revisit the vertical structure of black hole accretion disks in spherical coordinates. By comparing the advective cooling with the viscous heating, we show that advection-dominated disks are geometrically thick, i.e., with the…

High Energy Astrophysical Phenomena · Physics 2015-05-14 Wei-Min Gu , Li Xue , Tong Liu , Ju-Fu Lu

The standard equilibrium for radiation-dominated accretion disks has long been known to be viscously, thermally, and convectively unstable, but the nonlinear development of these instabilities---hence the actual state of such disks---has…

Astrophysics · Physics 2009-11-06 Eric Agol , Julian Krolik , Neal Turner , James Stone

We consider the role of advection in the two-temperature accreting corona with an underlying optically thick disc. The properties of coronal solutions depend significantly on the description of advection. Local parameterization of advection…

Astrophysics · Physics 2009-10-31 Agnieszka Janiuk , Piotr T. Zycki , Bozena Czerny

A self-consistent solution for a thin accretion disk with turbulent convection is presented. The disk viscosity and the convective flux are derived from a physical model for turbulence, and expressed in terms of the local physical…

Astrophysics · Physics 2009-10-28 Itzhak Goldman , Amri Wandel

Two-dimensional numerical simulations of an accretion flow in a close binary system are performed by solving the Euler equations with radiative transfer. In the present study, the specific heat ratio is assumed to be constant while…

Astrophysics · Physics 2009-11-07 Jun'ichi Sato , Keisuke Sawada , Naofumi Ohnishi

We present self-similar solutions for advection -dominated accretion flows with thermal conduction in the presence of outflows. Possible effects of outflows on the accretion flow are parametrized and a saturated form of thermal conduction,…

Astrophysics · Physics 2009-11-13 Mohsen Shadmehri
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