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Related papers: MRI: a possible mechanism for funnel flows?

200 papers

The magneto-rotational instability is presently the most promising source of turbulent transport in accretion disks. However, some important issues still need to be addressed to quantify the role of MRI in disks; in particular no systematic…

Astrophysics · Physics 2009-06-23 G. Lesur , P-Y. Longaretti

We investigate the possibility of the growth of magnetorotational instability (MRI) in disks around Class 0 protostars. We construct a disk model and calculate the chemical reactions of neutral and charged atoms, molecules and dust grains…

Solar and Stellar Astrophysics · Physics 2021-05-12 Yoshihiro Kawasaki , Shunta Koga , Masahiro N. Machida

Using local 3D MHD simulations, we investigate ways in which galactic turbulence associated with the magnetorotational instability (MRI) may influence the formation and properties of GMCs. Our disk models are vertically stratified and…

Astrophysics · Physics 2009-11-10 Woong-Tae Kim , Eve C. Ostriker , James M. Stone

The magnetorotational instability (MRI) is thought to be a powerful source of turbulence in Keplerian accretion disks. Motivated by recent laboratory experiments, we study the MRI driven by an azimuthal magnetic field in an electrically…

Solar and Stellar Astrophysics · Physics 2017-11-21 Anna Guseva , Ashley P. Willis , Rainer Hollerbach , Marc Avila

We examine the linear stability of a flow threaded by a weak, vertical magnetic field in a disk with a keplerian rotation profile and a vertical stratification of the ionization degree as that predicted for vast portions of protoplanetary…

Astrophysics · Physics 2009-10-31 Mauricio Reyes-Ruiz

In accretion disks with large-scale ordered magnetic fields, the magnetorotational instability (MRI) is marginally suppressed, so other processes may drive angular momentum transport leading to accretion. Accretion could then be driven by…

High Energy Astrophysical Phenomena · Physics 2018-05-16 Megan D. Marshall , Mark J. Avara , Jonathan C. McKinney

Neutrino radiation takes a major role in the momentum, heat, and lepton transports in proto-neutron stars (PNSs). These diffusive processes affect the growth of magnetorotational instability (MRI) in PNSs. We perform a local linear analysis…

Astrophysics · Physics 2008-11-26 Youhei Masada , Takayoshi Sano , Kazunari Shibata

The magnetorotational instability (MRI) is considered a key process for driving efficient angular momentum transport in astrophysical disks. Understanding its non-linear saturation constitutes a fundamental problem in modern accretion disk…

High Energy Astrophysical Phenomena · Physics 2012-05-25 Martin E. Pessah

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 present three-dimensional magnetohydrodynamic simulations of the nonlinear evolution of the magnetorotational instability (MRI) with a non-zero Ohmic resistivity. The properties of the saturated state depend on the initial magnetic field…

Astrophysics · Physics 2009-10-31 Timothy P. Fleming , James M. Stone , John F. Hawley

Turbulence in the protoplanetary disks induces collisions between dust grains, and thus facilitates grain growth. We investigate the two fundamental assumptions of the turbulence in obtaining grain collisional velocities -- the kinetic…

Solar and Stellar Astrophysics · Physics 2020-03-25 Munan Gong , Alexei V. Ivlev , Bo Zhao , Paola Caselli

Magnetorotational instability (MRI)-driven turbulence and dynamo phenomena are analyzed using direct statistical simulations. Our approach begins by developing a unified mean-field model that combines the traditionally decoupled problems of…

High Energy Astrophysical Phenomena · Physics 2025-05-07 Tushar Mondal , Pallavi Bhat

Activity of the nuclei of galaxies and stellar mass systems involving disk accretion to black holes is thought to be due to (1) a small-scale turbulent magnetic field in the disk (due to the magneto-rotational instability or MRI) which…

High Energy Astrophysical Phenomena · Physics 2009-08-05 R. V. E. Lovelace , D. M. Rothstein , G. S. Bisnovatyi-Kogan

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

Magnetorotational instability (MRI) is the most likely mechanism driving angular momentum transport in astrophysical disks. However, despite many efforts, a conclusive experimental evidence of MRI is still missing. Recently, performing 1D…

Fluid Dynamics · Physics 2023-07-31 A. Mishra , G. Mamatsashvili , F. Stefani

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

Angular momentum in protostellar discs can be transported either radially, through turbulence induced by the magnetorotational instability (MRI), or vertically, through the torque exerted by a large-scale magnetic field. We present a model…

Astrophysics · Physics 2009-11-13 Raquel Salmeron , Arieh Königl , Mark Wardle

We venture for the comparison between growth rates for magnetorotational instability (MRI) and hydrodynamics instability in the presence of an extra force in the local Keplerian accretion flow. The underlying model is described by the…

High Energy Astrophysical Phenomena · Physics 2022-05-27 Subham Ghosh , Banibrata Mukhopadhyay

We have investigated evolution of magneto-rotational instability (MRI) in protoplanetary disks that have radially non-uniform magnetic field such that stable and unstable regions coexist initially, and found that a zone in which the disk…

Astrophysics · Physics 2011-02-11 M. T. Kato , K. Nakamura , R. Tandokoro , M. Fujimoto , S. Ida

The magnetorotational instability (MRI) can destabilize hydrodynamically stable rotational flows, thereby allowing angular momentum transport in accretion disks. A notorious problem for MRI is its questionable applicability in regions with…

Solar and Stellar Astrophysics · Physics 2013-08-09 Oleg N. Kirillov , Frank Stefani