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Related papers: Magnetic stochasticity and diffusion

200 papers

Roles of turbulence in the context of magnetic reconnection are investigated with special emphasis on the mutual interaction between flow (large-scale inhomogeneous structure) and turbulence. In order to evaluate the effective transport due…

Solar and Stellar Astrophysics · Physics 2015-05-28 Nobumitsu Yokoi , Masahiro Hoshino

To understand magnetic diffusion, momentum transport, and mixing in the interior of the sun, we consider an idealized model of the tachocline, namely magnetohydrodynamics (MHD) turbulence on a $\beta$ plane subject to a large scale shear…

Astrophysics · Physics 2011-02-11 Nicolas Leprovost , Eun-Jin Kim

Reconnection is an important process that rules dissipation and diffusion of magnetic energy in plasmas. It is already clear that its rate is enhanced by turbulence, and that reconnection itself may increase its stochasticity, but the main…

Plasma Physics · Physics 2021-07-07 Natalia Nowak , Grzegorz Kowal , Diego A. Falceta-Gonçalves

We have calculated the general dispersion relationship for surface waves on a ferrofluid layer of any thickness and viscosity, under the influence of a uniform vertical magnetic field. The amplification of these waves can induce an…

Fluid Dynamics · Physics 2009-10-30 Berengere Abou , Gilles Neron de Surgy , Jose-Eduardo Wesfreid

We consider stochastic reconnection in a magnetized, partially ionized medium. Stochastic reconnection is a generic effect, due to field line wandering, in which the speed of reconnection is determined by the ability of ejected plasma to…

Plasma Physics · Physics 2009-11-10 A. Lazarian , E. T. Vishniac , J. Cho

Particle dynamics are investigated in plasma turbulence, using self-consistent kinetic simulations, in two dimensions. In steady state, the trajectories of single protons and proton-pairs are studied, at different values of plasma "beta"…

Plasma Physics · Physics 2016-08-31 S. Servidio , C. T. Haynes , W. H. Matthaeus , D. Burgess , V. Carbone , P. Veltri

We review the basic concepts of magnetic reconnection and propose a general framework for the astrophysical reconnection at large scales. Magnetic reconnection is the rearrangement of magnetic field topology. The conventional Sweet-Parker…

High Energy Astrophysical Phenomena · Physics 2018-06-18 Amir Jafari , Ethan Vishniac

Single-point measurements of fluctuations in the scrape-off layer of magnetized plasmas are generally found to be dominated by large-amplitude bursts which are associated with radial motion of blob-like structures. A stochastic model for…

Plasma Physics · Physics 2013-05-30 O. E. Garcia

Magnetic reconnection and turbulence are deeply intertwined in magnetohydrodynamic flows, yet how reconnection self-generates turbulence remains unclear. Using an ensemble of high-resolution three-dimensional direct numerical simulations of…

Plasma Physics · Physics 2026-02-26 Nick Williams , Alessandro De Rosis , Alex Skillen

Turbulence is the most common state of astrophysical flows. In typical astrophysical fluids, turbulence is accompanied by strong magnetic fields, which has a large impact on the dynamics of the turbulent cascade. Recently, there has been a…

Astrophysics · Physics 2011-05-10 Jungyeon Cho , A. Lazarian , Ethan Vishniac

We employ well-known concepts from statistical physics, quantum field theories and general topology to study magnetic reconnection, topology-change and their connection in incompressible flows in the context of an effective field theory…

Plasma Physics · Physics 2025-04-17 Amir Jafari

It is well known that magnetic fields constrain motions of charged particles, impeding the diffusion of charged particles perpendicular to magnetic field direction. This modification of transport processes is of vital importance for a wide…

Astrophysics of Galaxies · Physics 2015-03-19 A. Lazarian

Magnetic field fluctuations in MHD turbulence can be viewed as current sheets that are progressively more anisotropic at smaller scales. As suggested by Loureiro & Boldyrev (2017) and Mallet et al (2017), below a certain critical thickness…

Plasma Physics · Physics 2017-08-09 Stanislav Boldyrev , Nuno F. Loureiro

In numerical studies of turbulence, hyperviscosity is often used as a tool to extend the inertial subrange and to reduce the dissipative subrange. By analogy, hyperdiffusivity (or hyperresistivity) is sometimes used in magnetohydrodynamics.…

Astrophysics · Physics 2009-11-07 Axel Brandenburg , Graeme R. Sarson

To understand the basic mechanism of the formation of magnetic flux concentrations, we determine by direct numerical simulations the turbulence contributions to the mean magnetic pressure in a strongly stratified isothermal layer with large…

Solar and Stellar Astrophysics · Physics 2015-03-17 Axel Brandenburg , Koen Kemel , Nathan Kleeorin , Igor Rogachevskii

Realistic astrophysical environments are turbulent due to the extremely high Reynolds numbers. Therefore, the theories of reconnection intended for describing astrophysical reconnection should not ignore the effects of turbulence on…

High Energy Astrophysical Phenomena · Physics 2016-03-09 A. Lazarian , G. Kowal , M. Takamoto , E. M. de Gouveia Dal Pino , J. Cho

We present results from two-dimensional numerical simulations of a supersonic turbulent flow in the plane of the galactic disk, incorporating shear, thresholded and discrete star formation (SF), self-gravity, rotation and magnetic fields. A…

Astrophysics · Physics 2009-10-28 T. Passot , E. Vazquez-Semadeni , A. Pouquet

We study the diffusion process in a Heisenberg chain with correlated spatial disorder, with a power spectrum in the momentum space behaving as $k^{-\beta}$, using a stochastic description. It establishes a direct connection between the…

Statistical Mechanics · Physics 2007-05-23 M. H. Vainstein , R. Morgado , F. A. Oliveira , F. A. B. F. de Moura , M. D. Coutinho-Filho

In presence of an externally supported, mean magnetic field a turbulent, conducting medium, such as plasma, becomes anisotropic. This mean magnetic field, which is separate from the fluctuating, turbulent part of the magnetic field, has…

Plasma Physics · Physics 2018-12-07 Riddhi Bandyopadhyay , S. Oughton , M. Wan , W. H. Matthaeus , R. Chhiber , T. N. Parashar

The generation of turbulence at magnetized shocks and its subsequent interaction with the latter is a key question of plasma- and high-energy astrophysics. This paper presents two-dimensional magnetohydrodynamic simulations of a fast shock…

High Energy Astrophysical Phenomena · Physics 2018-01-09 Camilia Demidem , Martin Lemoine , Fabien Casse