Development of a High-Frequency Emissive Probe System for Plasma Potential Measurements in a Hall Thruster.

A heated emissive probe is a smart diagnostic tool for acquisition of the plasma potential in the discharge and in the plume of a Hall thruster. However, measurements of high-frequency oscillations of the potential require a specific electrical circuit with a low $RC$ time constant. We developed and tested an emissive probe system with a cutoff frequency of 1 MHz. Details about the low-pass filter design as well as first experimental outcomes obtained in the plume of a 200 W permanent magnet Hall thruster are given in this paper. [ABSTRACT FROM PUBLISHER]