Study on Plasma Acceleration in Completely Electrodeless Electric Propulsion System

Abstract

To solve a problem of a short lifetime due to a wear of the electrodes, we have been studying a completely electrodeless electric propulsion system. High-density (～1013 cm-3) helicon plasmas are being used for a dense source of our proposed system. Plasmas are accelerated by the Lorentz force in the axial direction, which is generated by the azimuthal current jθ induced in the plasma and the radial component of the external magnetic field Br. Here, this jθ can be generated by a Rotating Magnetic Field (RMF) scheme proposed. As an initial try of the plasma acceleration, we have measured electron density ne and ion velocity vi using the RMF method, and found that ne (vi) increased by a maximum of ～15% (16%) compared to those without RMF. These results were the first step that shows experimentally the effectiveness of RMF acceleration scheme in the electrodeless electric propulsion system.