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

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We study the effects of plasma \b{eta} (ratio of plasma pressure to magnetic pressure) on the evolution of kinetic plasma turbulence using fully kinetic particle-in-cell simulations of decaying turbulence. We find that the plasma \b{eta}…

Space Physics · Physics 2018-09-19 Tulasi N. Parashar , William H. Matthaeus , Michael A Shay

Turbulence in a conducting plasma can amplify seed magnetic fields in what is known as the turbulent, or small-scale, dynamo. The associated growth rate and emergent magnetic-field geometry depend sensitively on the material properties of…

High Energy Astrophysical Phenomena · Physics 2022-10-17 Alisa K. Galishnikova , Matthew W. Kunz , Alexander A. Schekochihin

The cross helicity (velocity--magnetic-field correlation) effects in the magnetic-field induction and momentum transport in the magnetohydrodynamic (MHD) turbulence are investigated with the aid of the multiple-scale renormalized…

Plasma Physics · Physics 2023-03-06 Nobumitsu Yokoi

The relaxation of a helical magnetic field ${\bf B}({\bf x}, t)$ in a high-conductivity plasma contained in the annulus between two perfectly conducting coaxial cylinders is considered. The plasma is of low density and its pressure is…

Plasma Physics · Physics 2017-12-06 Henry Keith Moffatt , Krzysztof Andrzej Mizerski

Using spatio-temporal spectra we show direct evidence of excitation of magnetosonic and Alfv\'en waves in three-dimensional compressible magnetohydrodynamic turbulence at small Mach numbers. For the plasma pressure dominated regime, or high…

Relativistic magnetically dominated turbulence is an efficient engine for particle acceleration in a collisionless plasma. Ultrarelativistic particles accelerated by interactions with turbulent fluctuations form non-thermal power-law…

Plasma Physics · Physics 2023-06-14 Cristian Vega , Stanislav Boldyrev , Vadim Roytershteyn

Magnetized plasmas with equilibrium density gradients support drift-wave turbulence, which is often regulated by self-generated zonal flows. In this work, we experimentally examine the effect of increasing the magnetic field on turbulence…

We present the first demonstration of the negative effective magnetic pressure instability in direct numerical simulations of stably stratified, externally forced, isothermal hydromagnetic turbulence in the regime of large plasma beta. By…

Solar and Stellar Astrophysics · Physics 2011-10-05 Axel Brandenburg , Koen Kemel , Nathan Kleeorin , Dhrubaditya Mitra , Igor Rogachevskii

Alfv\'enic-type turbulence in strongly magnetized, low-beta pair plasmas is investigated. A coupled set of equations for the evolution of the magnetic and flow potentials are derived, covering both fluid and kinetic scales. In the fluid…

Plasma Physics · Physics 2018-10-31 N. F. Loureiro , S. Boldyrev

The constraint imposed by magnetic helicity conservation on the alpha effect is considered for both magnetically and flow dominated self-organizing plasmas. Direct numerical simulations are presented for a dominant contribution to the alpha…

High Energy Astrophysical Phenomena · Physics 2015-06-18 F. Ebrahimi , A. Bhattacharjee

The excitation and further sustenance of large-scale magnetic fields in rotating astrophysical systems, including planets, stars and galaxies, is generally thought to involve a fluid magnetic dynamo effect driven by helical…

Fluid Dynamics · Physics 2021-12-10 F. Rincon

Quantifying transport by strongly stratified turbulence in low Prandtl number ($Pr$) fluids is critically important for the development of better models for the structure and evolution of stellar and planetary interiors. Motivated by recent…

Fluid Dynamics · Physics 2024-07-19 Kasturi Shah , Gregory P. Chini , Colm-cille P. Caulfield , Pascale Garaud

The transport of charged energetic particles in the presence of strong intermittent heliospheric turbulence is computationally analyzed based on known properties of the interplanetary magnetic field and solar wind plasma at 1 Astronomical…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Fathallah Alouani-Bibi , Jakobus A. le Roux

Using simulations of slowly rotating stratified turbulence, we show that the alpha effect responsible for the generation of astrophysical magnetic fields is proportional to the logarithmic gradient of kinetic energy density rather than that…

Solar and Stellar Astrophysics · Physics 2012-12-27 A. Brandenburg , O. Gressel , P. J. Käpylä , N. Kleeorin , M. J. Mantere , I. Rogachevskii

Plasma turbulence is the dominant transport mechanism for heat and particles in magnetized plasmas in linear devices and tokamaks, so the study of turbulence is important in limiting and controlling this transport. Linear devices provide an…

Plasma Physics · Physics 2017-11-17 Jarrod Leddy , Ben Dudson

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

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

The coefficients defining the mean electromotive force in a Galloway-Proctor flow are determined. This flow shows a two-dimensional pattern and is helical. The pattern wobbles in its plane. Apart from one exception a circular motion of the…

Astrophysics · Physics 2011-02-11 Karl-Heinz Rädler , Axel Brandenburg

In an inhomogeneous magnetised plasma the transport of energy and particles perpendicular to the magnetic field is in general mainly caused by quasi two-dimensional turbulent fluid mixing. The physics of turbulence and structure formation…

Plasma Physics · Physics 2010-03-05 Alexander Kendl

Numerical simulations with self-similar initial and boundary conditions provide a link between theoretical and numerical investigations of jet dynamics. We perform axisymmetric resistive magnetohydrodynamic (MHD) simulations for a…

Astrophysics · Physics 2009-11-13 Miljenko Cemeljic , Jose Gracia , Nektarios Vlahakis , Kanaris Tsinganos