Ion current and energy in the magnetic arch of a cluster of two ECR plasma sources.

Abstract

The feasibility of a novel 'magnetic arch' topology for controlled contactless plasma beam acceleration is experimentally demonstrated using a pair of coaxial electron cyclotron resonance sources with opposing magnetic polarities, such that their respective magnetic nozzles connect to form a closed-line configuration. Retarding potential analyser measurements are taken for a single source and the two sources with the same and opposing polarities, as well as no applied magnetic field, showing that the magnetic arch yields higher maximum ion current and lower plume divergence angle than other alternative configurations, albeit the most probable ion energy is lower than for a single magnetic nozzle, in agreement with existing models. This validation paves the way to clustering magnetic-nozzle-based plasma thrusters for space propulsion.