Electron and Ion Source ECR Plasma for Electric Propulsion Applications

Summary form only given. A permanent magnet ECR source previously investigated for plasma processing applications is being studied for potential electric propulsion applications such as main discharge ion production or plasma cathode electron production. The ECR surface is established using a permanent magnet grill. Intense ionization observed at the grill is probed using Langmuir probes, The energy distribution of ions emitted from the plasma production sites is measured using a retarding potential analyzer. Downstream electron saturation current is measured using a large collector electrode. The variation in the ion energy distribution, the electron saturation current, and ion saturation current as a function of operating condition and magnet geometry are documented and compared with a plasma diffusion model.