Hydromagnetic oscillations of a tangential discontinuity in the Chew, Goldberger, and Low approximation.
Abstract
The differential equation for linear modes of oscillation of plane parallel flows of plasmas along an external magnetic field in the Chew, Goldberger, and Low approximation is obtained. Properties of modes for a tangential discontinuity are studied for the case when the surface is modulated along the magnetic field. Overstable modes found by other authors are shown to be spurious. Regions of existence of modes, proper frequencies, and spatial dependence of the perturbation are given. It is found that, broadly speaking, low β plasmas should be free of surface instabilities for all values of the flow velocity, whereas high β plasmas can be unstable if the flow velocity is nearly sonic. Changes in the anisotropy do not substantially affect the general picture of the problem.
- Publication:
-
Physics of Fluids
- Pub Date:
- 1970
- DOI:
- 10.1063/1.1693110
- Bibcode:
- 1970PhFl...13.1503D