1. Fluid simulations of plasma turbulence at ion scales: comparison with Vlasov-Maxwell simulations
- Author
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I. Zouganelis, Francesco Valentini, Denise Perrone, Dimitri Laveder, Pierre-Louis Sulem, Pierluigi Veltri, Sergio Servidio, Thierry Passot, European Space Agency (ESA), Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), International Prevention Research Institute (IPRI), Laboratoire de Physique des Plasmas (LPP), Université Paris-Sud - Paris 11 (UP11)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École polytechnique (X)-Sorbonne Université (SU)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
- Subjects
NUMERICAL SCHEME ,Gyroradius ,Fluids & Plasmas ,FOS: Physical sciences ,01 natural sciences ,0203 Classical Physics ,SOLAR-WIND TURBULENCE ,CURRENT ADVANCE METHOD ,ENERGY CASCADE ,0202 Atomic, Molecular, Nuclear, Particle And Plasma Physics ,Physics, Fluids & Plasmas ,Physics::Plasma Physics ,physics.plasm-ph ,0103 physical sciences ,Landau damping ,010306 general physics ,Anisotropy ,010303 astronomy & astrophysics ,EQUATIONS ,ComputingMilieux_MISCELLANEOUS ,ASTROPHYSICAL GYROKINETICS ,Physics ,Science & Technology ,Turbulence ,MAGNETIC-FIELD ,Mechanics ,Plasma ,Condensed Matter Physics ,Physics - Plasma Physics ,Magnetic field ,Plasma Physics (physics.plasm-ph) ,0201 Astronomical And Space Sciences ,Physics::Space Physics ,Physical Sciences ,Compressibility ,Vector field ,MAGNETOHYDRODYNAMIC TURBULENCE ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,DISSIPATION RANGE ,INTEGRATION - Abstract
Comparisons are presented between a hybrid Vlasov-Maxwell (HVM ) simulation of turbulence in a collisionless plasma and fluid reductions. These includ e Hall- magnetohydrodynamics (HMHD) and Landau fluid (LF) or FLR-Land au fluid (FLR- LF) models that retain pressure anisotropy and low-frequency kin etic effects such as Landau damping and, for the last model, finite Larmor radius (FLR) c orrections. The problem is considered in two space dimensions, when initial conditio ns involve moderate-amplitude perturbations of a homogeneous equilibrium pla sma subject to an out-of-plane magnetic field. LF turns out to provide an accurat e description of the velocity field up to the ion Larmor radius scale, and even to smaller scales for the magnetic field. Compressibility nevertheless appears significant ly larger at the sub-ion scales in the fluid models than in the HVM simulation. High freque ncy ki- netic effects, such as cyclotron resonances, not retained by fluid descriptions, could be at the origin of this discrepancy. A significant temperature anisotr opy is generated, with a bias towards the perpendicular component, the more intense fluctuations being rather spread out and located in a broad vicinity of current sheets . Non-gyrotropic pressure tensor components are measured and their fluctuation s are shown to reach a significant fraction of the total pressure fluctuation, with inten se regions closely correlated with current sheets.
- Published
- 2018
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