Electron-scale reduced fluid models with gyroviscous effects - Équipe Systèmes dynamiques : théories et applications Accéder directement au contenu
Article Dans Une Revue Journal of Plasma Physics Année : 2017

Electron-scale reduced fluid models with gyroviscous effects

Résumé

Reduced fluid models for collisionless plasmas, including electron inertia and finite Larmor radius corrections, are derived for scales ranging from the ion to the electron gyroradii. Based either on pressure balance or on the incompressibility of the electron fluid, they respectively capture kinetic Alfvén waves (KAWs) or whistler waves (WWs), and can provide suitable tools for both reconnection and turbulence. Isothermal and Landau-fluid closures are considered. For small β e , a perturbative computation of the gyroviscous force valid at the electron inertial length is performed at order O(β e), which requires second-order contributions in a scale expansion. Anisotropy of pressure fluctuations enter the model equations in this regime. Comparisons with kinetic theory are performed in the linear regime, with special attention paid to the influence of Landau damping. The spectrum of transverse magnetic fluctuations in either strong or weak turbulence energy cascades is also phenomenologically predicted for both types of waves. New regimes, possibly related to the steep spectra observed in space plasmas in the sub-electron range, are obtained for KAWs at scales smaller than the electron inertial length, characterized by magnetic energy spectra decaying faster than those of WWs.
Fichier principal
Vignette du fichier
versionearxiv.pdf (983.18 Ko) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)
Loading...

Dates et versions

hal-01661283 , version 1 (11-12-2017)

Identifiants

Citer

Thierry Passot, P L Sulem, Emanuele Tassi. Electron-scale reduced fluid models with gyroviscous effects. Journal of Plasma Physics, 2017, 83 (4), pp.715830402. ⟨10.1017/S0022377817000514⟩. ⟨hal-01661283⟩
373 Consultations
73 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More