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Related papers: $\alpha$ Effect and Magnetic Diffusivity $\beta$ i…

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Using the test-field method for nearly irrotational turbulence driven by spherical expansion waves it is shown that the turbulent magnetic diffusivity increases with magnetic Reynolds numbers. Its value levels off at several times the rms…

Astrophysics of Galaxies · Physics 2010-11-05 Axel Brandenburg , Fabio Del Sordo

The backreaction of the Lorentz force on the alpha-effect is studied in the limit of small magnetic and fluid Reynolds numbers, using the first order smoothing approximation (FOSA) to solve both the induction and momentum equations. Both…

Astrophysics · Physics 2008-11-26 Sharanya Sur , Kandaswamy Subramanian , Axel Brandenburg

Recent advances in understanding of magnetohydrodynamic (MHD) turbulence call for revisions in the picture of particle acceleration. We make use of the recently established scaling of slow and fast MHD modes in strong and weak MHD…

Astrophysics · Physics 2016-08-30 Jungyeon Cho , A. Lazarian

Turbulence and magnetic fields are components of the interstellar medium and are interconnected through plasma processes. In particular, the magnetic flux transport in the presence of magneto-hydrodynamic (MHD) turbulence is an essential…

High Energy Astrophysical Phenomena · Physics 2025-07-30 C. N. Koshikumo , R. Santos-Lima , M. V. del Valle , E. M. de Gouveia Dal Pino , G. Guerrero , A. Lazarian

In the recent years, MRI-driven turbulent transport has been found to depend in a significant way on fluid viscosity $\nu$ and resistivity $\eta$ through the magnetic Prandtl number $Pm=\nu/\eta$. In particular, the transport decreases with…

Solar and Stellar Astrophysics · Physics 2015-05-18 P. -Y. Longaretti , G. Lesur

The relation of particle transport of relativistic particles in plasmas with high-amplitude isotropic sub-Larmor-scale magnetic turbulence to the spectra of radiation simultaneously produced by these particles is investigated both…

High Energy Astrophysical Phenomena · Physics 2013-07-16 Brett D. Keenan , Mikhail V. Medvedev

Observations in polarized emission reveal the existence of large-scale coherent magnetic fields in a wide range of spiral galaxies. Radio-polarization data show that these fields are strongly inclined towards the radial direction, with…

Astrophysics · Physics 2009-11-13 Oliver Gressel , Udo Ziegler , Detlef Elstner , Günther Rüdiger

It is shown that the transport in low temperature, collisional, bounded plasma is enhanced by instabilities at high magnetic field. While the magnetic field confines the electrons in a stable plasma, the instability completely destroys the…

Plasma Physics · Physics 2019-09-04 R. Lucken , A. Bourdon , M. Lieberman , P. Chabert

We study theoretically mode conversion and resonant overreflection of magnetohydrodynamic waves in an inhomogeneous plane-stratified plasma in the presence of a nonuniform shear flow, using precise numerical calculations of the reflection…

Plasma Physics · Physics 2022-12-21 Seulong Kim , Kihong Kim

A joint effect of the density-stratified turbulence (or inhomogeneous turbulence) and a large-scale shear for arbitrary Mach numbers results in the $\alpha$ effect and mean-field dynamo action. These effects also produce the effective…

Astrophysics of Galaxies · Physics 2026-03-19 Igor Rogachevskii , Nathan Kleeorin

The nonlinear state of a high-beta collisionless plasma is investigated when an imposed linear shear amplifies or diminishes a uniform magnetic field, driving pressure anisotropies and hence firehose/mirror instabilities. The evolution of…

High Energy Astrophysical Phenomena · Physics 2016-04-20 S. Melville , A. A. Schekochihin , M. W. Kunz

The Large Volume Plasma device(LVPD), a cylindrically shaped, linear plasma device of dimension( $\phi =2m $, $ L =3m $) have successfully demonstrated the excitation of Electron Temperature Gradient(ETG) turbulence[ Mattoo et al.,[1]]. The…

Using in situ data, accumulated in the turbulent magnetosheath by the Magnetospheric Multiscale (MMS) Mission, we report a statistical study of magnetic field curvature and discuss its role in the turbulent space plasmas. Consistent with…

To rigorously model fast ions in fusion plasmas, a non-Maxwellian equilibrium distribution must be used. In the work, the response of high-energy alpha particles to electrostatic turbulence has been analyzed for several different tokamak…

Plasma Physics · Physics 2015-05-13 George Wilkie , Ian Abel , Edmund Highcock , William Dorland

The transport of charged particles in various astrophysical environments permeated by magnetic fields is described in terms of a diffusion process, which relies on diffusion-tensor parameters generally inferred from Monte-Carlo simulations.…

High Energy Astrophysical Phenomena · Physics 2022-12-09 Olivier Deligny

Turbulence is often invoked to explain the origin of nonthermal particles in space and astrophysical plasmas. By means of 3D fully kinetic particle-in-cell simulations, we demonstrate that turbulence in low-$\beta$ plasmas ($\beta$ is the…

High Energy Astrophysical Phenomena · Physics 2022-09-16 Luca Comisso , Lorenzo Sironi

We explore some consequences of the ``alpha model,'' also called the ``Lagrangian-averaged'' model, for two-dimensional incompressible magnetohydrodynamic (MHD) turbulence. This model is an extension of the smoothing procedure in fluid…

Fluid Dynamics · Physics 2009-11-10 P. D. Mininni , D. C. Montgomery , A. G. Pouquet

Evolving magnetic fields are frequently embedded in plasmas that are turbulent. When the primary interest is in effects that are on a large scale compared to that of the turbulence, it is desirable to average over the turbulence to obtain…

Plasma Physics · Physics 2025-04-08 Allen H Boozer

We analyze statistically the energization of particles in a large scale environment of strong turbulence that is fragmented into a large number of distributed current filaments. The turbulent environment is generated through strongly…

Plasma Physics · Physics 2017-09-13 Heinz Isliker , Loukas Vlahos , Dana Constantinescu

Recent studies have outlined the interest for the evaluation of transport coefficients in space plasmas, where the observed velocity distributions of plasma particles are conditioned not only by the binary collisions, e.g., at low energies,…

Plasma Physics · Physics 2022-03-15 Edin Husidic , Klaus Scherer , Marian Lazar , Horst Fichtner , Stefaan Poedts