Accession Number:

AD0691747

Title:

THEORY OF STABILITY OF LARGE AMPLITUDE PERIODIC (BGK) WAVES IN COLLISIONLESS PLASMAS,

Descriptive Note:

Corporate Author:

CALIFORNIA UNIV LOS ANGELES PLASMA PHYSICS GROUP

Personal Author(s):

Report Date:

1969-06-01

Pagination or Media Count:

33.0

Abstract:

A method is developed for examining the stability of a large amplitude periodic BGK wave, Eo, in a collisionless plasma. Vlasovs equation is integrated by the method of characteristics to yield a polarization charge density response, linear in a small-amplitude field El, but nonlinear in Eo. The susceptibility linking charge density response El is expressed in terms of the exact orbits of trapped and untrapped particles in the field Eo, distributed in energy according to the assumed BGK distribution function, fo. These susceptibilities couple the Fourier components of El in the usual mode-coupling fashion, but trapping effects are now included. For fields Eo which are not too large, the mode-coupling problem reduces to finding the zeroes of a 2 x 2 or 3 x 3 determinant. Distribution functions which are localized at the bottom of the potential energy troughs of Eo give identically the growing side-band instability of Dawson, Kruer, and Sudan. Author

Subject Categories:

  • Plasma Physics and Magnetohydrodynamics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE