English
Related papers

Related papers: The Structure of Poloidal Fields Embedded in Thin …

200 papers

We study the stability of poloidal magnetic fields anchored in a thin accretion disc. The two-dimensional hydrodynamics in the disc plane is followed by a grid-based numerical simulation including the vertically integrated magnetic forces.…

Astrophysics · Physics 2015-06-24 R. Stehle , H. C. Spruit

We investigate the properties of a hot accretion flow bathed in a poloidal magnetic field. We consider an axisymmetric viscous resistive flow in the steady state configuration. We assume the dominant mechanism of energy dissipation is due…

High Energy Astrophysical Phenomena · Physics 2017-08-30 Maryam Samadi , Shahram Abbassi

We review the current theoretical models of the inward advection of the large scale external magnetic fields in accretion discs. The most plausible theories for launching astrophysical jets rely on strong magnetic fields at the inner parts…

High Energy Astrophysical Phenomena · Physics 2019-04-24 Amir Jafari

In this paper, we develop the analysis of a two-dimensional magnetohydrodynamical configuration for an axially symmetric and rotating plasma (embedded in a dipole like magnetic field), modeling the structure of a thin accretion disk around…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Giovanni Montani , Riccardo Benini

The magnetic fields of accretion disks play an important role in studying their evolution. We may assume that its generation is connected to the dynamo mechanism, which is similar with that in the galactic disks. Here, we propose a model of…

High Energy Astrophysical Phenomena · Physics 2021-08-11 Daniela V. Boneva , Evgeny A. Mikhailov , Maria V. Pashentseva , Dmitriy D. Sokoloff

We use global magnetohydrodynamic simulations to study the influence of net vertical magnetic fields on the structure of geometrically thin ($H/r \approx 0.05$) accretion disks in the Newtonian limit. We consider initial mid-plane gas to…

High Energy Astrophysical Phenomena · Physics 2020-01-23 Bhupendra Mishra , Mitchell C. Begelman , Philip J. Armitage , Jacob B. Simon

We present global magnetohydrodynamic (MHD) simulations of accretion disks with a strong toroidal magnetic field using an equation of state that fixes the gas thermal scale height. The disk forms from the inflow of a rotating magnetized gas…

High Energy Astrophysical Phenomena · Physics 2025-05-20 Minghao Guo , Eliot Quataert , Jonathan Squire , Philip F. Hopkins , James M. Stone

We show that a large-scale, weak magnetic field threading a turbulent accretion disk tends to be advected inward, contrary to previous suggestions that it will be stopped by outward diffusion. The efficient inward transport is a consequence…

Astrophysics · Physics 2009-11-13 David M. Rothstein , Richard V. E. Lovelace

We investigate the effects of a large-scale magnetic field with open field lines on the steady-state structure of a radiation-dominated accretion disk, using self-similarity technique. The disk is supposed to be turbulent and possesses an…

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

Motivated by indirect observational evidence for strongly magnetized accretion discs around black holes, and the novel theoretical properties of such solutions, we investigate how a strong magnetization state can develop and persist. To…

High Energy Astrophysical Phenomena · Physics 2016-06-01 Greg Salvesen , Philip J. Armitage , Jacob B. Simon , Mitchell C. Begelman

In earlier works we pointed out that the disk's surface layers are non-turbulent and thus highly conducting (or non-diffusive) because the hydrodynamic and/or magnetorotational (MRI) instabilities are suppressed high in the disk where the…

High Energy Astrophysical Phenomena · Physics 2015-05-30 G. S. Bisnovatyi-Kogan , R. V. E. Lovelace

Axisymmetric steady-state weakly ionized Hall-MHD Keplerian thin disks are investigated by using asymptotic expansions in the small disk aspect ratio \epsilon. The model incorporates the azimuthal and poloidal components of the magnetic…

Astrophysics · Physics 2015-05-27 Yuri M. Shtemler , Michael Mond , Gunther Rudiger

We present an analytic, quasi-local model for accretion discs threaded by net, vertical magnetic flux. In a simple slab geometry and ignoring stochastic mean-field dynamo effects, we calculate the large-scale field resulting from the…

High Energy Astrophysical Phenomena · Physics 2024-10-18 Mitchell C. Begelman

We investigate the stability to nonaxisymmetric perturbations of an accretion disc in which a poloidal magnetic field provides part of the radial support against gravity. Interchange instability due to radial gradients in the magnetic field…

Astrophysics · Physics 2015-06-24 H. C. Spruit , R. Stehle , J. C. B. Papaloizou

Giant planets embedded in protoplanetary disks (PPDs) can create annulus density gaps around their orbits in the type-II regime, potentially responsible for the ubiquity of annular substructures observed in PPDs. Despite of substantial…

Earth and Planetary Astrophysics · Physics 2024-07-23 Yuhiko Aoyama , Xuening Bai

We construct a simple model for stationary, axisymmetric black-hole magnetospheres, in which the poloidal magnetic field is generated by a toroidal electric current in a thin disk with the inner edge, by solving the vacuum Maxwell equations…

Astrophysics · Physics 2009-10-31 Akira Tomimatsu , Masaaki Takahashi

The results of three-dimensional MHD numerical simulations are used to investigate the characteristic properties of the magnetic-field structures in the accretion disks of semi-detached binary systems. It is assumed that the intrinsic…

Solar and Stellar Astrophysics · Physics 2010-07-21 A. G. Zhilkin , D. V. Bisikalo

The gas dynamics of weakly ionized protoplanetary disks (PPDs) is largely governed by the coupling between gas and magnetic fields, described by three non-ideal magnetohydrodynamical (MHD) effects (Ohmic, Hall, ambipolar). Previous local…

Earth and Planetary Astrophysics · Physics 2017-08-23 Xue-Ning Bai

We analyze an axisymmetric magnetohydrodynamics configuration, describing the morphology of a purely differentially rotating thin plasma disk, in which linear and non-linear perturbations are triggered associated with microscopic magnetic…

Solar and Stellar Astrophysics · Physics 2018-10-02 Giovanni Montani , Mariachiara Rizzo , Nakia Carlevaro

Describing the large-scale field topology of protoplanetary disks faces significant difficulties and uncertainties. The transport of the large-scale field inside the disk plays an important role in understanding its evolution. We aim to…

Solar and Stellar Astrophysics · Physics 2025-11-26 D. Steiner , L. Gehrig , M. Güdel
‹ Prev 1 2 3 10 Next ›