Automodulation of Ion Oscillation Modes in Plasma

Abstract

Automodulation of ion oscillation mode is investigated by applying the reductive perturbation theory to the fluid equation of a plasma composed of cold ions and isothermal electrons. It is shown that an oscillatory solution of the Korteweg-de Vries equation in the small wave number region satisfies a small wave number limit of the nonlinear Schrödinger type equation obtained in the finite wave number region.