Ion Heating in a Supersonic Plasma Flow for an Advanced Plasma Thruster

Abstract : Ion heating experiments are performed in a fast flowing plasma with an ion Mach number of nearly unity. RF waves with an ion cyclotron range of frequency is excited by a pair of loop antennas located at a divergent magnetic nozzle. Increase of plasma thermal energy W(perpendicular to) measured by a diamagnetic coil is observed when the waves are excited with various azimuthal mode numbers in several magnetic nozzle configurations. It is most effective to heat ions of plasma flow to excite the waves with an azimuthal mode number of m= 1. The heating efficiency is larger in the magnetic beach configuration than that in the uniform one.