Observation of Parametric Instability Induced by Beam-Plasma Interaction

Abstract
A convectively unstable beam-plasma wave is excited and observed to grow and saturate. In the saturation region, the beam wave excites by parametric interaction an ion-acoustic wave and a backward-propagating Trivelpiece-Gould mode. Significant energy is deposited into these modes, and this suggests that pump depletion may play a role in the saturation process.