Dispersion of long MHD waves in a finely structured plasma

Citation
M. Lontano et al., Dispersion of long MHD waves in a finely structured plasma, PHYS SCR, T84, 2000, pp. 52-56
Citations number
8
Categorie Soggetti
Physics
Journal title
PHYSICA SCRIPTA
ISSN journal
02811847 → ACNP
Volume
T84
Year of publication
2000
Pages
52 - 56
Database
ISI
SICI code
0281-1847(2000)T84:<52:DOLMWI>2.0.ZU;2-K
Abstract
The propagation of long magnetohydrodynamic waves (with wavelength lambda) in a plasma characterized by small scale (of the order of a), large amplitu de nonuniformities of its density and of the magnetic held is investigated in conditions where lambda >> a. The introduction of a suitable averaging p rocedure over an intermediate scale allows one to obtain the relevant dispe rsion relation for the long waves which manifests new properties with respe ct to those of a uniform plasma. Moreover, it is shown that, if the plasma nonuniformities are spatially distributed with a broad spectrum, within a f inite interval of numerical values, a collisionless mechanism of damping ma y affect the slow mode. The results of this work are of concern both For as trophysical and laboratory plasmas.