Detuning effect of negative ions on oscillating-two-stream instabilities of electromagnetic waves

Abstract

It is proved analytically in the three-fluid theory of a plasma that the effect of negative ions on the oscillating-two-stream instability results in a change of the frequency mismatch between the electromagnetic pump and the electron plasma wave. Ion thermal and collision terms are assumed to be negligible. This negative ion effect can completely detune and suppress the instability, if the number density ratio of negative to positive ions is greater than 2(upsilon(0)(2)/upsilon(th)(2)), where upsilon(0) is the oscillation velocity amplitude of electrons under the pump and upsilon(th) is the electron thermal speed. (C) 1996 American Institute of Physics.