MHD leaky waves in a layered plasma. I: Theory. II: Mechanism of leakage. III: Numerical solutions
type: Item
instance of: scholarly article
title: MHD leaky waves in a layered plasma. I: Theory. II: Mechanism of leakage. III: Numerical solutions
zbMATH Open document ID: 0944.76022
DOI: 10.1023/A:1001129427867
author: Alejandro G. González
author: S. Farina
author: Julio Gratton
published in: Astrophysics and Space Science
publication date: 1999-11-11T00:00:00Z
review text: The authors investigate the stability of compressible perfectly conducting plasma layers that are imbedded in two-dimensional varying magnetic field. The investigation is limited by the linear stability analysis. The authors find stationary magnetohydrodynamic equilibrium states for three-layer plasma. The matching of the perturbations of two uniform media at their interface is described by a matrix equation. Using the standard technique, the authors obtain four different dispersion relations. In part I the general theory of MHD leaky waves is presented. Part II is devoted to the discussion of the physical mechanism of leakage. Four basic leakage mechanisms are established: surface modes, single interface modes, trapped waves, and lost insulation leakage modes. All mechanisms can be clearly separated only in the limiting cases. The complex branches of the roots of the dispersion relation correspond to leaky waves, and in general case it is not possible to classify the waves. Part III presents numerical calculations of complex frequencies of leaky waves. It is shown that the wave spectra consist of an infinite set of branches. Several of four leakage mechanisms can operate in real plasma configurations. Since no restrictions are imposed on the configuration, the presented methods allow to investigate arbitrary cases.
Mathematics Subject Classification ID: 76E25
Mathematics Subject Classification ID: 76X05
Mathematics Subject Classification ID: 76W05
Mathematics Subject Classification ID: 82D10
zbMATH DE Number: 1338031
zbMATH Keywords: MHD stability
zbMATH Keywords: compressible perfectly conducting plasma layers
zbMATH Keywords: two-dimensional varying magnetic field
zbMATH Keywords: linear stability analysis
zbMATH Keywords: magnetohydrodynamic equilibrium states
zbMATH Keywords: three-layer plasma
zbMATH Keywords: matrix equation
zbMATH Keywords: dispersion relations
zbMATH Keywords: MHD leaky waves
zbMATH Keywords: surface modes
zbMATH Keywords: single interface modes
zbMATH Keywords: trapped waves
zbMATH Keywords: lost insulation leakage modes
zbMATH Keywords: numerical calculations of complex frequencies
zbMATH Keywords: wave spectra
reviewed by: Oleg A. Sinkevich
MaRDI profile type: Publication
full work available at URL: a:1001129427867
OpenAlex ID: W1653048886
description: scientific article; zbMATH DE number 1338031