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Related papers: Angular momentum transport in accretion disks

200 papers

We consider an extreme case of disc accretion onto a gravitating centre when the viscosity in the disc is negligible. The angular momentum and the rotational energy of the accreted matter is carried out by a magnetized wind outflowing from…

Astrophysics · Physics 2010-04-28 Sergei Bogovalov , Stanislav Kelner

Conversion of gravitational energy into radiation in accretion discs and the origin of large scale magnetic fields in astrophysical rotators have often been distinct topics of research. In semi-analytic work on both problems it has been…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Eric G. Blackman

The non-linear fluid dynamics of a warped accretion disc was investigated in an earlier paper by developing a theory of fully non-linear bending waves in a thin, viscous disc. That analysis is here extended to take proper account of thermal…

Astrophysics · Physics 2009-10-31 G. I. Ogilvie

Axisymmetric accretion disks in vicinity of a central compact body are studied. For the simple models such as vertically isothermal disks as well as adiabatic ones the exact solutions to the steady-state MHD (magneto-hydrodynamic) system…

Solar and Stellar Astrophysics · Physics 2013-09-06 V. S. Borisov

(Abridged) We study the dynamical evolution of a stationary, axisymmetric, and perfectly conducting cold accretion disk containing a large-scale magnetic field around a Kerr black hole, trying to understand the relation between accretion…

Astrophysics · Physics 2009-11-07 Li-Xin Li

We present a linear analysis of the stability of accretion disks in which angular momentum is removed by the magnetic torque exerted by a centrifugally driven wind. The effects of the dependence of the wind torque on field strength and…

Astrophysics · Physics 2009-11-07 Xinwu Cao , H. C. Spruit

We present the first results of a global axisymmetric simulation of accretion onto rotating magnetized stars from a turbulent, MRI-driven disk. The angular momentum is transported outward by the magnetic stress of the turbulent flow with a…

Solar and Stellar Astrophysics · Physics 2015-05-27 Marina M. Romanova , Galina V. Ustyugova , Alexander V. Koldoba , Richard V. E. Lovelace

Axisymmetric accretion disks in vicinity of a central compact body are studied. In the case of non-viscous disk it is proven that all solutions for the midplane circular velocity are unstable. Hence, the pure hydrodynamic turbulence in…

Fluid Dynamics · Physics 2020-06-30 V. S. Borisov

Disk accretion onto a weakly magnetized central object, e.g. a star, is inevitably accompanied by the formation of a boundary layer near the surface, in which matter slows down from the highly supersonic orbital velocity of the disk to the…

Solar and Stellar Astrophysics · Physics 2015-06-05 Mikhail A. Belyaev , Roman R. Rafikov , James M. Stone

Recently, the vertical shear instability (VSI) has become an attractive purely hydrodynamic candidate for the anomalous angular momentum transport required for weakly ionized accretion disks. In direct three-dimensional numerical…

Solar and Stellar Astrophysics · Physics 2017-03-08 Moritz H. R. Stoll , Giovanni Picogna , Wilhelm Kley

We have considered precession in accretion disks in which a second moment of inertia relative to an axis perpendicular to the axis of rotation may be very important. This formalism, that takes into account the precession contribution to the…

Astrophysics · Physics 2007-10-17 Cesar Meirelles Filho

Accretion disc theory was first developed as a theory with the local heat balance, where the whole energy produced by a viscous heating was emitted to the sides of the disc. One of the most important new invention of this theory was a…

Astrophysics · Physics 2016-01-27 G. S. Bisnovatyi-Kogan

In this paper, we extend our previous analysis (Lodato & Rice 2004) of the transport properties induced by gravitational instabilities in cooling, gaseous accretion discs to the case where the disc mass is comparable to the central object.…

Astrophysics · Physics 2009-11-10 G. Lodato , W. K. M. Rice

We present a scaling law that predicts the values of the stresses obtained in numerical simulations of saturated MRI-driven turbulence in non-stratified shearing boxes. It relates the turbulent stresses to the strength of the vertical…

Astrophysics · Physics 2009-11-13 Martin E. Pessah , Chi-kwan Chan , Dimitrios Psaltis

The evolution of thin axisymmetric viscous accretion disks is a classic problem in astrophysics. While models based on this simplified geometry provide only approximations to the true processes of instability-driven mass and angular…

Instrumentation and Methods for Astrophysics · Physics 2015-02-25 Mark R. Krumholz , John C. Forbes

We investigate the radial transport of magnetic flux in a thin accretion disc, the turbulence being modelled by effective diffusion coefficients (viscosity and resistivity). Both turbulent diffusion and advection by the accretion flow…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Jerome Guilet , Gordon I. Ogilvie

In the classical transport theory, the coefficients such as the diffusion, thermal conductivity and viscosity of fluid are usually expressed in a form proportional to the mean free path of molecules. We point out that this may cause a great…

Statistical Mechanics · Physics 2021-12-14 Xiaofeng Yang , Luyao Shang , Jian Sui

The purpose of this paper is to explore the dynamical behaviour of hot accretion flow with thermal conduction. The importance of thermal conduction on hot accretion flow is confirmed by observations of the hot gas that surrounds Sgr A$^*$…

High Energy Astrophysical Phenomena · Physics 2012-05-11 Kazem Faghei

The existence of outflow in accretion flows is confirmed by observations and magnetohydrodynamics (MHD) simulations. In this paper, we study outflows of accretion flows in the presence of resistivity and toroidal magnetic field. The…

High Energy Astrophysical Phenomena · Physics 2012-05-11 Kazem Faghei , Azam Mollatayefeh

Current-driven reconnection is investigated as a possible mechanism for angular momentum transport in astrophysical disks. A theoretical and computational study of angular momentum transport from current-driven magnetohydrodynamic…

High Energy Astrophysical Phenomena · Physics 2015-05-30 F. Ebrahimi , S. C. Prager