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Related papers: On dynamics of geometrically thin accretion disks

200 papers

We present a magneto-hydrodynamic model developed for investigations of advective non-stationary, asymmetric Keplerian accretion disks in the normal magnetic field. The introduced model allows us to trace the evolution in different fixed…

High Energy Astrophysical Phenomena · Physics 2014-08-19 Krasimira Yankova , Lachezar Filipov

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

This paper studies the nonlinear evolution of magnetic field turbulence in proximity of steady ideal MHD configurations characterized by a small electric current, a small plasma flow, and approximate flux surfaces, a physical setting that…

Plasma Physics · Physics 2024-09-12 Naoki Sato , Michio Yamada

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

We present three-dimensional MHD simulations of rotating radiatively inefficient accretion flows onto black holes. In the simulations, we continuously inject magnetized matter into the computational domain near the outer boundary, and we…

Astrophysics · Physics 2009-11-07 Igor V. Igumenshchev , Ramesh Narayan , Marek A. Abramowicz

The steady-state structure of self-gravitating, magnetized accretion disks is studied using a set of self-similar solutions which are appropriate in the outer regions. The disk is assumed to be isothermal and the magnetic field outside of…

Astrophysics · Physics 2009-11-13 Mohsen Shadmehri , Fazeleh Khajenabi

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

We discuss the basic hydrodynamics that determines the density structure of the disks around hot stars. Observational evidence supports the idea that these disks are Keplerian (rotationally supported) gaseous disks. A popular scenario in…

Astrophysics · Physics 2009-11-13 A. C. Carciofi , J. E. Bjorkman

We consider a class of steady-state self-gravitating accretion disks for which efficient cooling mechanisms are assumed to operate so that the disk is self-regulated at a condition of approximate marginal Jeans stability. In an earlier…

Astrophysics · Physics 2007-05-23 G. Bertin , G. Lodato

Astrophysical disks are likely embedded in an ambient vertical magnetic field. This ambient field is known to drive magneto-rotational turbulence in the disk bulk but is also responsible for the launching of magnetized outflows at the…

High Energy Astrophysical Phenomena · Physics 2021-03-31 J. Jacquemin-Ide , G. Lesur , J. Ferreira

Thermal instability is examined for advection-dominated one-temperature accretion disks. We consider axisymmetric perturbations with short wavelength in the radial direction. The viscosity is assumed to be sufficiently small for the…

Astrophysics · Physics 2015-06-24 Shoji Kato , Marek A. Abramowicz , Xingming Chen

Whether tidal disruption events circularise or accrete directly as highly eccentric discs is the subject of current research and appears to depend sensitively on the disc thermodynamics. One aspect of this problem that has not received much…

High Energy Astrophysical Phenomena · Physics 2020-11-18 Elliot M. Lynch , Gordon I. Ogilvie

We explore the properties of cold gravitoturbulent accretion disks - non-fragmenting disks hovering on the verge of gravitational instability - using a realistic prescription for the effective viscosity caused by gravitational torques. This…

Earth and Planetary Astrophysics · Physics 2009-10-02 Roman R. Rafikov

We present the results of four magnetohydrodynamic simulations and one alpha-disk simulation of accretion disks in a compact binary system, neglecting vertical stratification and assuming a locally isothermal equation of state. We…

High Energy Astrophysical Phenomena · Physics 2024-11-26 Morgan Ohana , Yan-Fei Jiang , Omer Blaes , Bryance Oyang

We consider vertical heat transport in Keplerian accretion disks, including the effects of radiation, convection, and turbulent mixing driven by the Balbus-Hawley instability, in astronomical systems ranging from dwarf novae (DNe), and soft…

Astrophysics · Physics 2009-10-31 Pin-Gao Gu , Ethan T. Vishniac , John K. Cannizzo

We present magnetohydrodynamic simulations of a resistive accretion disk continuously launching transmagnetosonic, collimated jets. We time-evolve the full set of magnetohydrodynamic equations, but neglect radiative losses in the energetics…

Astrophysics · Physics 2009-11-10 Fabien Casse , Rony Keppens

The magnetorotational instability originates from the elastic coupling of fluid elements in orbit around a gravitational well. Since inertial accelerations play a fundamental dynamical role in the process, one may expect substantial…

Astrophysics · Physics 2009-11-07 Rafael Angel Araya-Gochez

We want to test if self-similar magneto-hydrodynamic (MHD) accretion-ejection models can explain the observational results for accretion disk winds in BHBs. In our models, the density at the base of the outflow, from the accretion disk, is…

High Energy Astrophysical Phenomena · Physics 2016-05-25 S. Chakravorty , P-O. Petrucci , J. Ferreira , G. Henri , R. Belmont , M. Clavel , S. Corbel , J. Rodriguez , M. Coriat , S. Drappeau , J. Malzac

We study the oscillations of an axisymmetric, viscous, radiative, general relativistic hydrodynamical simulation of a geometrically thin disk around a non-rotating, $6.62\,M_\odot$ black hole. The numerical setup is initialized with a…

High Energy Astrophysical Phenomena · Physics 2018-12-05 Bhupendra Mishra , Wlodek Kluzniak , P. Chris Fragile

The standard thin disk model predicts that when the accretion rate is over a small fraction of the Eddington rate, which corresponds to $L \ga 0.06 L_{Edd}$, the inner region of the disk is radiation-pressure-dominated and thermally…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Sheng-Ming Zheng , Feng Yuan , Wei-Min Gu , Ju-Fu Lu