Variable operation of Hall thruster with multiple segmented electrodes

Variable plasma jet velocity with low beam divergence over a range of mass flow rates can be achieved through segmented electrode operation of the Hal l plasma accelerator. With the use of just a cathode side electrode at the cathode potential, the beam divergence can be decreased substantially, at s ome cost in efficiency. However, the additional use of an anode side electr ode retains the same reduced plume divergence, but at efficiencies comparab le to the nonsegmented operation. The high efficiency persists also when th e anode side electrode is biased at an intermediate potential, thus produci ng two-stage Hall accelerator operation. (C) 2001 American Institute of Phy sics.