Parametric excitation of drift-cyclotron instability in plasma

Parametric excitation of drift and cyclotron oscillations in a weakly inhomogeneous plasma in an alternating electric field with a frequency of the order of the ion cyclotron frequency is considered for the case where the relative velocity of electrons and ions is considerably less than the thermal velocity of the ions. Expressions are derived for the growth increments and instability thresholds. The stabilizing role of ion-ion collisions is considered. The significance of these instabilities in HF plasma heating is noted. (author)