The Interaction of a Large Amplitude Travelling Wave with a Cylindrical Plasma

Abstract

In connection with the problem of radio frequency heating of plasma, the interaction of a high power wave (0.1 GWatts) with a cylindrical plasma is investigated experimentally for frequencies near the ion cyclotron frequency and in the region between the ion cyclotron frequency and the lower hybrid frequency. It is found that a geometric resonance can be excited in which more than 90% of the wave energy is absorbed by the plasma. At frequencies around the ion cyclotron frequency, the macroscopic properties of the plasma, including distortion of the wave by large amplitude effects, can be fairly well explained by a MHD-model assuming an anomalous resistivity. The enlarged collision frequency is attributed to the presence of turbulence which is excited by drift currents connected with the wave.