Plasma Beta Dependence of Magnetic Compressibility in Solar Wind Turbulence - Archive ouverte HAL Accéder directement au contenu
Poster De Conférence Année : 2014

Plasma Beta Dependence of Magnetic Compressibility in Solar Wind Turbulence

S. C. Chapman
  • Fonction : Auteur
B. Hnat
  • Fonction : Auteur
K. H. Kiyani
  • Fonction : Auteur
Fouad Sahraoui

Résumé

The turbulent signature of MHD scales in the near-Earth solar wind are known to be primarily incompressible which manifests itself in magnetic field fluctuation vector components to be aligned primarily perpendicular to the background magnetic field − so-called "Variance Anisotropy". This, and other facts, have been seen as evidence for a majority Alfvenic turbulence cascade; with a small component (10%) of compressible fluctuations. When one approaches scales on the order of the ion-inertial length and the Larmor radius, this behaviour changes and it is now becoming increasingly evident that the spectral break at these scales is also accompanied by an increase in magnetic compressibility. This has been attributed to a phase change in the physics at these scales − from fluid to kinetic − and in particular to the dominant role of the Hall-effect at sub-ion scales. We will be presenting results from the Cluster mission to show how this increase in the compressibility is dependent on the ion plasma beta and what implications this has for the physics at sub-ion scales in the context of prominent theories and models for kinetic plasma turbulence.
Fichier non déposé

Dates et versions

hal-02861679 , version 1 (09-06-2020)

Identifiants

  • HAL Id : hal-02861679 , version 1

Citer

S. C. Chapman, B. Hnat, K. H. Kiyani, Fouad Sahraoui. Plasma Beta Dependence of Magnetic Compressibility in Solar Wind Turbulence. American Geophysical Union, Fall Meeting, Dec 2014, San Francisco, California, United States. 33, pp.SH33A-4141, 2014. ⟨hal-02861679⟩
61 Consultations
0 Téléchargements

Partager

Gmail Facebook X LinkedIn More