Ion Velocity and Plasma Potential Measurements of a Cylindrical Cusped Field Thruster

Measurements of the most probable time-averaged axial ion velocities and plasma potential within the acceleration channel and in the plume of a straightchanneled cylindrical cusped field thruster operating on xenon are presented. Ion velocities for the thruster are derived from laser-induced fluorescence measurements of the 5d[4]7/2 −6p[3]5/2 xenon ion excited state transition centered at λ = 834.72 nm. Plasma potential measurements are made using a floating emissive probe with a thoriated-tungsten filament. The thruster is operated in a power matched condition with 300 V applied anode potential for comparison to previous krypton plasma potential measurements, and a low power condition with 150 V applied anode potential. Correlations are seen between the plasma potential drop outside of the thruster and kinetic energy contours of ions with increasing velocity.