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Related papers: Fluctuation Dynamo in a Collisionless, Weakly Magn…

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We investigate the inverse cascade of magnetic energy in decaying, collisionless plasmas with moderate to high-$\beta$ values via first-principles numerical simulations and analytical theory. We find that pressure-anisotropy-driven…

Plasma Physics · Physics 2025-10-03 Zhuo Liu , Muni Zhou , Nuno F. G. Loureiro

Both global dynamics and turbulence in magnetized weakly collisional cosmic plasmas are described by general magnetofluid equations that contain pressure anisotropies and heat fluxes that must be calculated from microscopic plasma kinetic…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 A. A. Schekochihin , S. C. Cowley , F. Rincon , M. S. Rosin

The MHD equations, as a collisional fluid model that remains in local thermodynamic equilibrium (LTE), have long been used to describe turbulence in myriad space and astrophysical plasmas. Yet, the vast majority of these plasmas, from the…

High Energy Astrophysical Phenomena · Physics 2024-09-30 S. Majeski , M. W. Kunz , J. Squire

{\em Voyager 1} and {\em 2} data reveals that magnetic field fluctuations are compressive and exhibit a Gaussian distribution in the compressed heliosheath plasma, whereas they follow a lognormal distribution in a nearly incompressible…

Space Physics · Physics 2015-05-18 Dastgeer Shaikh

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 selfgenerated wave fluctuations are particularly interesting in the solar wind and magnetospheric plasmas, where Coulomb collisions are rare and cannot explain the observed states of quasi-equilibrium. Linear theory predicts that the…

Solar and Stellar Astrophysics · Physics 2015-06-16 M. Lazar , S. Poedts , R. Schlickeiser , D. Ibscher

The intracluster medium of galaxy clusters is an extremely hot and diffuse, nearly collisionless plasma, which hosts dynamically important magnetic fields of $\sim \mu {\rm G}$ strength. Seed magnetic fields of much weaker strength of…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-17 Radhika Achikanath Chirakkara , Amit Seta , Christoph Federrath , Matthew W. Kunz

A weak fluctuating magnetic field embedded into a turbulent conducting medium grows exponentially while its characteristic scale decays. In the ISM and protogalactic plasmas, the magnetic Pr is very large, so a broad spectrum of growing…

Astrophysics · Physics 2008-11-26 Alexander Schekochihin , Steven Cowley , Jason Maron , Leonid Malyshkin

The mechanisms that generate "seed" magnetic fields in our Universe and that amplify them throughout cosmic time remain poorly understood. By means of fully-kinetic particle-in-cell simulations of turbulent, initially unmagnetized plasmas,…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-09 L. Sironi , L. Comisso , R. Golant

Fluctuation dynamos are thought to play an essential role in magnetized galaxy evolution, saturating within $\sim0.01~$Gyr and thus potentially acting as seeds for large-scale dynamos. However, unambiguous observational confirmation of the…

Astrophysics of Galaxies · Physics 2021-01-20 Amit Seta , Luiz Felippe S. Rodrigues , Christoph Federrath , Christopher A. Hales

Weak turbulence of magnetohydrodynamic (MHD) waves in strongly magnetized plasma is studied when the thermal pressure is less than the magnetic field pressure. In this situation the main nonlinear mechanism is the resonance scattering of…

Plasma Physics · Physics 2009-11-07 Evgenii A. Kuznetsov

Energy dissipation in collisionless plasmas is one of the most outstanding open questions in plasma physics. Magnetic reconnection and turbulence are two phenomena that can produce the conditions for energy dissipation. These two phenomena…

Attention is drawn to a fundamental difference between the physical mechanisms responsible for the magnetic field freezing-in effect in spatially isotropic (collisional) and strongly anisotropic (collisionless) plasmas. (The first case is…

Astrophysics · Physics 2007-05-23 Yu. V. Dumin

Depending on the physical conditions involved the beam plasma systems may reveal new unstable regimes triggered by the wave instabilities of different nature. We show through linear theory and numerical simulations the existence of an…

Plasma Physics · Physics 2020-10-05 R. A. López , M. Lazar , S. M. Shaaban , S. Poedts , P. S. Moya

The nonlinear evolution of the Kelvin Helmholtz instability in a magnetized plasma with a perpendicular flow close to, or in, the supermagnetosonic regime can produce a significant parallel-to-perpendicular pressure anisotropy. This…

Space Physics · Physics 2016-02-17 S. De Camillis , S. S. Cerri , F. Califano , F. Pegoraro

Galaxy clusters host a hot, diffuse plasma with poorly understood viscosity and magnetic field amplification. Astrophysical plasmas are often modeled with magnetohydrodynamics (MHD), but low collision rates in environments like the…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-17 S. Adduci Faria , R. Santos-Lima , E. M. de Gouveia Dal Pino

According to magnetohydrodynamics (MHD), the encounter of two collisional magnetized plasmas at high velocity gives rise to shock waves. Investigations conducted so far have found that the same conclusion still holds in the case of…

Plasma Physics · Physics 2017-05-24 Antoine Bret , Asaf Pe'er , Lorenzo Sironi , Aleksander Sadowski , Ramesh Narayan

I calculate the linear stability of a stratified low collisionality plasma in the presence of a weak magnetic field. Heat is assumed to flow only along magnetic field lines. In the absence of a heat flux in the background plasma, Balbus…

Astrophysics · Physics 2009-11-13 Eliot Quataert

We investigate electromagnetic buoyancy instabilities of the electron-ion plasma with the heat flux based on not the magnetohydrodynamic (MHD) equations, but using the multicomponent plasma approach when the momentum equations are solved…

Astrophysics of Galaxies · Physics 2015-05-27 Anatoly Nekrasov , Mohsen Shadmehri

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