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Related papers: Fluctuation Dynamo in Collisionless and Weakly Col…

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Weakly collisional space plasmas are rarely in local thermal equilibrium and often exhibit non-Maxwellian electron and ion velocity distributions that lead to the growth of microinstabilities, that is, enhanced electric and magnetic fields…

We investigate the Lagrangian mechanism of the kinematic ``fluctuation'' magnetic dynamo in turbulent plasma flow at small magnetic Prandtl numbers. The combined effect of turbulent advection and plasma resistivity is to carry infinitely…

Plasma Physics · Physics 2015-05-13 Gregory L. Eyink , Antonio F. Neto

The relationship between a decaying strong turbulence and the mirror instability in a slowly expanding plasma is investigated using two-dimensional hybrid expanding box simulations. We impose an initial ambient magnetic field perpendicular…

Space Physics · Physics 2017-04-12 P. Hellinger , S. Landi , L. Matteini , A. Verdini , L. Franci

We investigate an efficient mechanism for generating magnetic fields in turbulent, collisionless plasmas. By using fully kinetic, particle-in-cell simulations of an initially non-magnetized plasma, we inspect the genesis of magnetization,…

Plasma Physics · Physics 2021-12-01 F. Pucci , M. Viviani , F. Valentini , G. Lapenta , W. H. Matthaeus , S. Servidio

A theoretical framework for low-frequency electromagnetic (drift-)kinetic turbulence in a collisionless, multi-species plasma is presented. The result generalises reduced magnetohydrodynamics (RMHD) and kinetic RMHD (Schekochihin et al.…

High Energy Astrophysical Phenomena · Physics 2015-07-22 M. W. Kunz , A. A. Schekochihin , C. H. K. Chen , I. G. Abel , S. C. Cowley

In this work we report a numerical study of the cosmic magnetic field amplification due to collisionless plasma instabilities. The collisionless magnetohydrodynamic equations derived account for the pressure anisotropy that leads, in…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-06 D. Falceta-Goncalves , G. Kowal

When a cylindrically-symmetric magnetized plasma compresses or expands, velocity-space anisotropy is naturally generated as a result of the different adiabatic conservation laws parallel and perpendicular to the magnetic field. When the…

Plasma Physics · Physics 2023-05-18 Ian E. Ochs , Nathaniel J. Fisch

Using two-dimensional hybrid-kinetic simulations, we explore the nonlinear "interruption" of standing and traveling shear-Alfv\'en waves in collisionless plasmas. Interruption involves a self-generated pressure anisotropy removing the…

Plasma Physics · Physics 2017-12-14 J. Squire , M. W. Kunz , E. Quataert , A. A. Schekochihin

Theoretical approaches to low-frequency magnetized turbulence in collisionless and weakly collisional astrophysical plasmas are reviewed. The proper starting point for an analytical description of these plasmas is kinetic theory, not fluid…

Astrophysics · Physics 2009-11-11 A. A. Schekochihin , S. C. Cowley , W. Dorland

Diffuse accretion flows near a supermassive black hole are fundamentally weakly collisional. In such weakly collisional plasmas, the ion and electron distribution functions can deviate significantly from thermal equilibrium, and particle…

High Energy Astrophysical Phenomena · Physics 2026-04-08 Abhishek Hegade K. R. , James M. Stone

Microscopic instability and macroscopic flow pattern resulting from colliding plasmas are studied analytically in support of laboratory experiments. The plasma flows are assumed to stream radially from two separate centers. In a…

Plasma Physics · Physics 2018-11-13 Mikhail Malkov , Vladimir Sotnikov

We present results from three-dimensional hybrid-kinetic simulations of Alfv\'enic turbulence in a high-beta, collisionless plasma. The key feature of such turbulence is the interplay between local wave--wave interactions between the…

High Energy Astrophysical Phenomena · Physics 2023-03-03 Lev Arzamasskiy , Matthew W. Kunz , Jonathan Squire , Eliot Quataert , Alexander A. Schekochihin

Dynamic mitigation is presented for filamentation instability and magnetic reconnection in a plasm driven by a wobbling electron sheet current. The wobbling current introduces an oscillating perturbation and smooths the perturbation. The…

Plasma Physics · Physics 2021-01-21 Yan-Jun Gu , Shigeo Kawata , Sergei V. Bulanov

Plasmoid-driven magnetic reconnection in elongated current sheets is suspected to be an ubiquitous phenomenon in space and astrophysical plasmas, but the mechanisms driving its onset and dynamics are still debated. Deciphering the physical…

Observations of the intracluster medium (ICM) in galaxy clusters suggest for the presence of turbulence and the magnetic fields existence has been proved through observations of Faraday Rotation and synchrotron emission. The ICM is also…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-09 M. S. Nakwacki , G. Kowal , R. Santos-Lima , E. M. de Gouveia Dal Pino , D. A. Falceta-Gonçalves

We study the dynamics of magnetic fields in chiral magnetohydrodynamics, which takes into account the effects of an additional electric current related to the chiral magnetic effect in high energy plasmas. We perform direct numerical…

Plasma Physics · Physics 2022-02-15 Jennifer Schober , Igor Rogachevskii , Axel Brandenburg

We study the evolution of collisionless plasmas that, due to their macroscopic evolution, are susceptible to the firehose instability, using both analytic theory and hybrid-kinetic particle-in-cell simulations. We establish that, depending…

High Energy Astrophysical Phenomena · Physics 2025-07-15 A. F. A. Bott , M. W. Kunz , E. Quataert , J. Squire , L Arzamasskiy

The low-frequency instability of a cylindrical poorly magnetized plasma with an inward-directed radial electric field is studied changing the gas pressure and the ion cyclotron frequency. The unstable frequency always decreases when the gas…

Plasma Physics · Physics 2016-05-25 Thiery Pierre

Dynamos wherein magnetic field is produced from velocity fluctuations are fundamental to our understanding of several astrophysical and/or laboratory phenomena. Though fluid helicity is known to play a key role in the onset of dynamo…

Plasma Physics · Physics 2023-07-05 Shishir Biswas , Rajaraman Ganesh

Observations of galaxy clusters show that the intracluster medium (ICM) is likely to be turbulent and is certainly magnetized. The properties of this magnetized turbulence are determined both by fundamental nonlinear magnetohydrodynamic…

Astrophysics · Physics 2008-11-26 A. A. Schekochihin , S. C. Cowley