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Related papers: Magnetostrophic MRI in the Earth's Outer Core

200 papers

We investigated the impacts of magnetorotational instability (MRI) on the dynamics of weakly magnetized, rapidly rotating core-collapse by conducting high resolution MHD simulations in axisymmetry with simplified neutrino transfer. We found…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Hidetomo Sawai , Shoichi Yamada

Eccentric disks arise in such astrophysical contexts as tidal disruption events, but it is unknown whether the magnetorotational instability (MRI), which powers accretion in circular disks, operates in eccentric disks as well. We examine…

High Energy Astrophysical Phenomena · Physics 2020-01-24 Chi-Ho Chan , Julian H. Krolik , Tsvi Piran

The inner structure of the earth is still a topic of discussion. Seismic measurements showed a structure of solid, liquid, solid which describes the mantle, outer core and inner core with the inner core in the center. The analysis of…

Earth and Planetary Astrophysics · Physics 2013-03-19 M. Wolf

Differential rotation occurs in conducting flows in accretion disks and planetary cores. In such systems, the magnetorotational instability can arise from coupling Lorentz and centrifugal forces to cause large radial angular momentum…

The magnetorotational instability (MRI) triggers turbulence and enables outward transport of angular momentum in hydrodynamically stable rotating shear flows, e.g., in accretion disks. What laws of differential rotation are susceptible to…

Solar and Stellar Astrophysics · Physics 2012-07-13 Oleg N. Kirillov , Frank Stefani

The merger of two neutron stars may give birth to a long-lived hypermassive neutron star. If it harbours a strong magnetic field of magnetar strength, its spin-down could explain several features of short gamma-ray burst afterglows. The…

High Energy Astrophysical Phenomena · Physics 2017-08-23 Jerome Guilet , Andreas Bauswein , Oliver Just , Hans-Thomas Janka

We investigate the linear growth and vertical structure of the magnetorotational instability (MRI) in weakly ionised, stratified accretion discs. The magnetic field is initially vertical and dust grains are assumed to have settled towards…

Astrophysics · Physics 2009-11-10 Raquel Salmeron , Mark Wardle

The magnetorotational instability (MRI) plays a key role in the formation of stars and black holes, by enabling outward angular momentum transport in accretion disks. The use of combined axial and azimuthal magnetic fields allows the…

We study local magnetohydrodynamical (MHD) instabilities of differential rotation in magnetised, stably-stratified regions of stars and planets using a Cartesian Boussinesq model. We consider arbitrary latitudes and general shears (with…

Solar and Stellar Astrophysics · Physics 2024-10-10 Robert W. Dymott , Adrian J. Barker , Chris A. Jones , Steven M. Tobias

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

We study how the magnetorotational instability (MRI) in protoplanetary disks is affected by the electric discharge caused by the electric field in the resistive MHD. We have performed three-dimensional shearing box simulations with various…

Solar and Stellar Astrophysics · Physics 2015-06-11 Takayuki Muranushi , Satoshi Okuzumi , Shu-ichiro Inutsuka

Magnetorotational instability (MRI) is one of the most important and most common instabilities in astrophysics, it is widely accepted that it serves as a source of turbulent viscosity in accretion disks -- the most energy efficient objects…

Astrophysics · Physics 2007-05-23 J. Szklarski

A linear but global numerical model for the magnetorotational instability (MRI) in disk geometry is considered to estimate the instability parameters for galaxies. Similarity rules suggested by a local analysis are applied to reveal a…

Astrophysics · Physics 2016-08-16 L. L. Kitchatinov , G. Rüdiger

The geomagnetic field has undergone hundreds of polarity reversals over Earth's history, at a variable pace. In numerical models of Earth's core dynamics, reversals occur with increasing frequency when the convective forcing is increased…

Geophysics · Physics 2025-05-09 Julien Aubert , Maylis Landeau , Alexandre Fournier , Thomas Gastine

A global mode is shown to be unstable to non-axisymmetric perturbations in a differentially rotating Keplerian disk containing either vertical or azimuthal magnetic fields. In an unstratified cylindrical disk model, using both global…

High Energy Astrophysical Phenomena · Physics 2022-09-13 Fatima Ebrahimi , Matthew Pharr

We investigate the evolution of hydromagnetic perturbations in a small section of accretion disks. It is known that molecular viscosity is negligible in accretion disks. Hence, it has been argued that a mechanism, known as Magnetorotational…

High Energy Astrophysical Phenomena · Physics 2015-08-12 Sujit Kumar Nath , Banibrata Mukhopadhyay

The Global Magnetorotational Instability (MRI) is investigated for a configuration in which the rotation frequency changes only in a narrow transition region. If the vertical wavelength of the unstable mode is of the same order or smaller…

Instrumentation and Methods for Astrophysics · Physics 2011-02-11 J. Pino , S. M. Mahajan

We analyze the morphology of the Magneto-rotational Instability (MRI) for a stratified viscous plasma disk configuration in differential rotation, taking into account the so-called corotation theorem for the background profile. In order to…

Plasma Physics · Physics 2017-04-26 Nakia Carlevaro , Giovanni Montani , Fabrizio Renzi

(Abriged) The magnetorotational instability (MRI) is believed to be an efficient way to transport angular momentum in accretion discs. It has also been suggested as a way to amplify magnetic fields in discs, the instability acting as a…

Astrophysics · Physics 2009-11-13 G. Lesur , G. I. Ogilvie

The magnetorotational instability (MRI) is thought to play a key role in the formation of stars and black holes by sustaining the turbulence in hydrodynamically stable Keplerian accretion discs. In previous experiments the MRI was observed…