English
Related papers

Related papers: Steady-State Solutions for a Geometrically Thin Ac…

200 papers

Magnetically-arrested disks (MADs) appear when accretion flows are supplied with a sufficient amount of magnetic flux. In this work, we use results of magnetohydrodynamic simulations to set the configuration of the magnetic field and…

High Energy Astrophysical Phenomena · Physics 2020-01-31 Fu-Guo Xie , Andrzej A. Zdziarski

Models of planet-disk interaction are mainly based on 2D and 3D viscous hydrodynamical simulations. Accretion is classically prescribed by an alpha parameter which characterizes the turbulent radial transport of angular momentum (AM) in the…

Solar and Stellar Astrophysics · Physics 2023-05-22 Gaylor Wafflard-Fernandez , Geoffroy Lesur

The existence of outflow and magnetic field in the inner region of hot accretion flows have been confirmed by observations and numerical magnetohydrodynamic simulations (MHD). We present self-similar solutions for radiation inefficiently…

Astrophysics of Galaxies · Physics 2015-06-05 S. Abbassi , A. Mosallanezhad

We present the results of hydrodynamical simulations of the disk photosphere irradiated by strong X-rays produced in the inner most part of the disk. As expected, the irradiation heats the photosphere and drives a thermal wind. To apply our…

High Energy Astrophysical Phenomena · Physics 2015-05-18 S. Luketic , D. Proga , T. R. Kallman , J. C. Raymond , J. M. Miller

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

We construct Super-Eddington Slim Disks models around both stellar and super-massive black holes by allowing the formation of a porous layer with a reduced effective opacity. We show that at high accretion rates, the inner part of the disks…

High Energy Astrophysical Phenomena · Physics 2015-05-18 Calanit Dotan , Nir J. Shaviv

We apply the semi-analytical analysis of the steady nature of line-driven winds presented in two earlier papers to disk winds driven by the flux distribution of a standard Shakura & Sunyaev (1973) disk for typical cataclysmic variable (CV)…

Astrophysics · Physics 2009-11-11 Nicolas A. Pereyra , David A. Turnshek , D. John Hillier

We describe an analytic model for an evolving protoplanetary disk driven by viscosity and a disk wind. The disk is heated by stellar irradiation and energy generated by viscosity. The evolution is controlled by 3 parameters: (i) the inflow…

Earth and Planetary Astrophysics · Physics 2020-05-20 John Chambers

Magnetohydrodynamic accretion disk simulations suggest that much of the energy liberated by the magnetorotational instability (MRI) can be channeled into large-scale toroidal magnetic fields through dynamo action. Under certain conditions,…

High Energy Astrophysical Phenomena · Physics 2015-08-19 Mitchell C. Begelman , Philip J. Armitage , Christopher S. Reynolds

The classical radiation pressure instability has been a persistent theoretical feature of thin, radiatively efficient accretion disks with accretion rates 1 to 100 per cent of the Eddington rate. But there is only limited evidence of its…

High Energy Astrophysical Phenomena · Physics 2023-07-05 Karamveer Kaur , Nicholas C. Stone , Shmuel Gilbaum

We present a 3-D ideal MHD simulation of magnetospheric accretion onto a non-rotating star. The accretion process unfolds with intricate 3-D structures driven by various mechanisms. First, the disc develops filaments at the magnetospheric…

Solar and Stellar Astrophysics · Physics 2023-12-18 Zhaohuan Zhu , James M. Stone , Nuria Calvet

We report on a new class of solutions of black hole accretion disks that we have found through three-dimensional, global, radiative magnetohydrodynamic simulations in general relativity. It combines features of the canonical thin, slim and…

We develop an analytical model for the accretion and gravitational drag on a point mass that moves hypersonically in the midplane of a gaseous disk with a Gaussian vertical density stratification. Such a model is of interest for studying…

Astrophysics of Galaxies · Physics 2015-06-12 J. Cantó , A. Esquivel. F. J. Sánchez-Salcedo , A. C. Raga

We present a general linear dispersion relation which describes the coupled behavior of magnetorotational, photon bubble, and convective instabilities in weakly magnetized, differentially rotating accretion disks. We presume the accretion…

Astrophysics · Physics 2009-10-31 Omer Blaes , Aristotle Socrates

Aims: We determine the steady-state of an axisymmetric thin accretion disc with an internal dynamo around a magnetised star. Methods: Starting from the vertically integrated equations of magnetohydrodynamics we derive a single ordinary…

High Energy Astrophysical Phenomena · Physics 2010-01-26 Solomon Belay Tessema , Ulf Torkelsson

Global three dimensional magnetohydrodynamic (MHD) simulations of turbulent accretion disks are presented which start from fully equilibrium initial conditions in which the magnetic forces are accounted for and the induction equation is…

High Energy Astrophysical Phenomena · Physics 2015-06-12 E. R. Parkin , G. V. Bicknell

We describe an efficient method of calculating the radiation pressure due to spectral lines, including all the terms in the velocity gradient tensor. We apply this method to calculate the two-dimensional, time-dependent structure of winds…

Astrophysics · Physics 2009-10-31 D. Proga , J. M. Stone , J. E. Drew

Planetary migration is a key link between planet formation models and observed exoplanet statistics. So far the theory of migration has focused on the interaction of planets with an inviscid or viscously evolving disk. Turbulent viscosity…

Earth and Planetary Astrophysics · Physics 2019-12-25 C. N. Kimmig , C. P. Dullemond , W. Kley

Grid-based magnetohydrodynamic (MHD) simulations have proven invaluable for the study of astrophysical accretion disks. However, the fact that angular momentum transport in disks is mediated by MHD turbulence (with structure down to very…

High Energy Astrophysical Phenomena · Physics 2015-05-28 Kareem A. Sorathia , Christopher S. Reynolds , James M. Stone , Kris Beckwith

We perform global three-dimensional simulations of accretion disks integrating the compressible, non-viscous, but diffusive MHD equations. The disk is supposed to be isothermal. We make use of the ZEUS-3D code integrating the MHD equations…

Astrophysics · Physics 2009-11-06 R. Arlt , G. Rudiger