English
Related papers

Related papers: Magnetorotational instability in eccentric disks

200 papers

The magnetorotational instability(MRI) in the Kerr spacetime is studied on a 3+1 viewpoint. The Maxwell's equations are expressed in a circularly orbiting observer's frame that co-rotates with matter in Keplerian orbits. There exist large…

Astrophysics · Physics 2009-11-10 M. Yokosawa , T. Inui

A new type of instability that is expected to drive magnetohydrodynamic (MHD) turbulence from a purely toroidal magnetic field in an accretion disk is presented. It is already known that in a differentially rotating system, the uniform…

High Energy Astrophysical Phenomena · Physics 2016-05-25 Kota Hirabayashi , Masahiro Hoshino

It has been recently suggested that the magneto-rotational instability (MRI) is a limiting case of the magneto-elliptic instability (MEI). This limit is obtained for horizontal modes in the presence of rotation and an external vertical…

Fluid Dynamics · Physics 2015-06-04 Krzysztof A. Mizerski , Wladimir Lyra

We revisit the modal analysis of small perturbations in Keplerian ideal gas flows leading to magneto-rotational instability (MRI) using the non-local approach. We consider the case of constant vertical background magnetic field, as well as…

High Energy Astrophysical Phenomena · Physics 2023-12-19 Nikolay Shakura , Konstantin Postnov , Dmitry Kolesnikov , Galina Lipunova

The magnetorotational instability (MRI) is key physics in accretion disks and is widely considered to play some role in massive-star core collapse. Models of rotating massive stars naturally develop very strong shear at composition…

Solar and Stellar Astrophysics · Physics 2015-06-23 J. Craig Wheeler , Daniel Kagan , Emmanouil Chatzopoulos

Many dynamical interactions can induce eccentricities in astrophysical accretion disks. Disk eccentricities in turn seed a variety of instabilities, even in ideal hydrodynamics. We use 3D nonlinear simulations and 2+1D linear calculations…

Solar and Stellar Astrophysics · Physics 2025-10-30 Janosz W. Dewberry , Henrik N. Latter , Gordon I. Ogilvie , Sebastien Fromang

We propose that the strength of angular momentum transport in accretion discs threaded by net vertical magnetic field is determined by a self-regulation mechanism: the magnetorotational instability (MRI) grows until its own turbulent…

High Energy Astrophysical Phenomena · Physics 2023-04-18 Mitchell C. Begelman , Philip J. Armitage

The saturation of the magnetorotational (MRI) instability in thin Keplerian disks through three wave resonant interactions is introduced and discussed. That mechanism is a natural generalization of the fundamental decay instability…

Plasma Physics · Physics 2015-06-16 Yuri Shtemler , Edward Liverts , Michael Mond

The linear instability of thin, vertically-isothermal Keplerian discs, under the influence of axial magnetic field is investigated. Solutions of the stability problem are found explicitly by asymptotic expansions in the small aspect ratio…

Solar and Stellar Astrophysics · Physics 2015-06-03 E. Liverts , Yu. Shtemler , M. Mond

Possible effects of magnetic fields in core collapse supernovae rely on an efficient amplification of the weak pre-collapse fields. It has been suggested that the magneto-rotational instability (MRI) leads to rapid field growth. Although…

Astrophysics · Physics 2009-05-06 M. Obergaulinger , P. Cerdà-Duràn , E. Müller , M. A. Aloy

We calculate growth rates for nonaxisymmetric instabilities including the magnetorotational instability (MRI) throughout the Sun. We first derive a dispersion relation for nonaxisymmetric instability including the effects of shear,…

Solar and Stellar Astrophysics · Physics 2015-06-22 Daniel Kagan , J. Craig Wheeler

Magnetorotational instability (MRI) has been suggested to lead a rapid growth of the magnetic field in core collapse supernovae and produce departures from spherical syymmetry that can be important in determining the explosion mechanism. We…

Solar and Stellar Astrophysics · Physics 2015-05-14 V. Urpin

An evolution of a magnetic reconnection in a collisionless accretion disk is investigated using a 2.5 dimensional hybrid code simulation. In astrophysical disks, magnetorotational instability (MRI) is considered to play an important role by…

Earth and Planetary Astrophysics · Physics 2014-07-03 Keisuke Shirakawa , Masahiro Hoshino

In this paper we develop a framework for studying unstratified, magnetised eccentric discs and compute uniformly precessing eccentric modes in a cylindrical annulus which provide convenient initial conditions for numerical simulations. The…

High Energy Astrophysical Phenomena · Physics 2023-09-18 Elliot M. Lynch , Janosz W. Dewberry

In this paper, we analyze the linear stability of a stellar accretion disk, having a stratified morphology. The study is performed in the framework of ideal magneto-hydrodynamics and therefore it results in a characterization of the linear…

High Energy Astrophysical Phenomena · Physics 2016-01-20 G. Montani , D. Pugliese

We carried out 2D-axisymmetric MHD simulations of core-collapse supernovae for rapidly-rotating magnetized progenitors. By changing both the strength of the magnetic field and the spatial resolution, the evolution of the magnetorotational…

High Energy Astrophysical Phenomena · Physics 2016-02-03 Hidetomo Sawai , Shoichi Yamada

The magneto-rotational instability (MRI) is the most likely mechanism for transportation of angular momentum and dissipation of energy within hot, ionized accretion discs. This instability is produced through the interactions of a…

High Energy Astrophysical Phenomena · Physics 2021-12-08 Oscar M. Pimentel , P. Chris Fragile , F. D. Lora-Clavijo , Bridget Ierace , Deepika Bollimpalli

The magnetorotational instability (MRI) is a fundamental process of accretion disk physics, but its saturation mechanism remains poorly understood despite considerable theoretical and computational effort. We present a multiple scales…

High Energy Astrophysical Phenomena · Physics 2017-05-24 S. E. Clark , Jeffrey S. Oishi

We consider discs that orbit a central object and are tidally perturbed by a circular orbit companion. Such discs are sometimes subject to an eccentric instability due to the effects of certain resonances. Eccentric instabilities may be…

Solar and Stellar Astrophysics · Physics 2015-05-18 Stephen H. Lubow

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