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Title: Damping of magnetohydrodynamic disturbances in multi-ion-species plasmas

Abstract

The evolution of macroscopic magnetohydrodynamic disturbances across a magnetic field is studied, with particular attention to the effect of multiple ion species. Analyses are carried out on disturbances where the initial magnetic profiles are sinusoidal. Both the theory and electromagnetic simulations show that, in a single-ion-species plasma, the disturbance is undamped, with its energy oscillating between the magnetic field and ion velocity. In a multi-ion-species plasma, however, it is initially damped, owing to the phase mixing of the magnetosonic mode and the modes having ion-ion hybrid cutoff frequencies. Furthermore, it is found from long-time simulations that the amplitude of the disturbance continues to decrease in a multi-ion-species plasma. This is due to nonlinear mode couplings. The magnetic energy is irreversibly transferred to the ions.

Authors:
; ;  [1]
  1. Department of Physics, Nagoya University, Nagoya 464-8602 (Japan)
Publication Date:
OSTI Identifier:
20782730
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 13; Journal Issue: 4; Other Information: DOI: 10.1063/1.2188404; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AMPLITUDES; CHARGED-PARTICLE TRANSPORT; DAMPING; DISTURBANCES; ION ACOUSTIC WAVES; IONS; MAGNETIC FIELDS; MAGNETOHYDRODYNAMICS; NONLINEAR PROBLEMS; PLASMA; PLASMA INSTABILITY; PLASMA SIMULATION; VELOCITY

Citation Formats

Toida, Mieko, Yoshiya, Takashi, and Ohsawa, Yukiharu. Damping of magnetohydrodynamic disturbances in multi-ion-species plasmas. United States: N. p., 2006. Web. doi:10.1063/1.2188404.
Toida, Mieko, Yoshiya, Takashi, & Ohsawa, Yukiharu. Damping of magnetohydrodynamic disturbances in multi-ion-species plasmas. United States. doi:10.1063/1.2188404.
Toida, Mieko, Yoshiya, Takashi, and Ohsawa, Yukiharu. Sat . "Damping of magnetohydrodynamic disturbances in multi-ion-species plasmas". United States. doi:10.1063/1.2188404.
@article{osti_20782730,
title = {Damping of magnetohydrodynamic disturbances in multi-ion-species plasmas},
author = {Toida, Mieko and Yoshiya, Takashi and Ohsawa, Yukiharu},
abstractNote = {The evolution of macroscopic magnetohydrodynamic disturbances across a magnetic field is studied, with particular attention to the effect of multiple ion species. Analyses are carried out on disturbances where the initial magnetic profiles are sinusoidal. Both the theory and electromagnetic simulations show that, in a single-ion-species plasma, the disturbance is undamped, with its energy oscillating between the magnetic field and ion velocity. In a multi-ion-species plasma, however, it is initially damped, owing to the phase mixing of the magnetosonic mode and the modes having ion-ion hybrid cutoff frequencies. Furthermore, it is found from long-time simulations that the amplitude of the disturbance continues to decrease in a multi-ion-species plasma. This is due to nonlinear mode couplings. The magnetic energy is irreversibly transferred to the ions.},
doi = {10.1063/1.2188404},
journal = {Physics of Plasmas},
number = 4,
volume = 13,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}
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