Evidence of the ionization instability and ion acoustic turbulence correlation in sub-ampere hollow cathodes

Abstract Plasma instabilities in the plume of hollow cathodes have been extensively researched particular for high-current operation. The rise mode ionization-like instability leads to a degradation cathode’s performance along with emergence highly energetic ions that can produce sputtering various surfaces. Numerical simulations using 2D fluid or hybrid codes brought forward an interesting correlation between evolution ion acoustic turbulence (IAT) and oscillations. Such numerical findings were proven be true by experimental measurements wave dispersion mode-IAT emitting currents >10 A. This study brings evidence oscillations IAT low-current operating Kr at sub-ampere current levels. It is shown <1 A correlated anomalous electron collision drives transport cathode plume. fluctuations energy lead large temperature which then drive density via ionization.