Low-Frequency Sheath Instability in a Non-Maxwellian Plasma with Energetic Ions

The low-frequency sheath instability in non-Maxwellian plasma produced by resonant absorption of short microwave pulse was investigated. The instability with its characteristic frequency lower than the ion-plasma frequency occurred in the sheath of positively biased electrode irradiated by an energetic ion flux due to disruption of the ion flux. The ion beam disruption occurred due to the time-of-flight effect and the beam density inside the sheath decreased which led the sheath back to its initial unperturbed state. The results show that this phenomena occurred in space and laboratory plasma with non-Maxwellian ion distributions which was used as a diagnostic of the energetic ion in plasma.