Characteristics of jets from stationary plasma thrusters under different operating conditions

The characteristics of jets from laboratory models of SPT-100 and SPT-140 electric propulsion engines are studied. These engines are based on plasma accelerators with a closed electron drift and extended acceleration zone. The characteristics studied are the accelerated ion current density distribution over the angle of deviation of ions movement direction from the axis of the engine and the energy distribution of ions moving along different directions. These parameters are studied with the thrusters operating at elevated discharge voltages providing high velocities of the plasma flow from the engine. Obtained data make it possible to study the variation of these parameters, as well as the divergence of the jet and spatial distribution of the energy transferred by accelerated ions, with engine operating conditions.