LAUSR

Abstract To investigate electron extraction through the orifice of an electron cyclotron resonance (ECR) neutralizer, two-dimensional axisymmetric particle-in-cell simulations with a Monte Carlo collision algorithm (PIC-MCC) have been conducted. The diagnostic experiment of Langmuir probe verified that the plasma distribution in the ECR neutralizer with an L-shaped antenna was circumferentially uniform, which provided the experimental basis for two-dimensional axisymmetric simulations. The distribution of plasma parameters and extracted electron current of the neutralizer were obtained by tracking the motion of electrons and singly charged xenon ions, simulating the elasticity, excitation, ionization and Coulomb collisions. Moreover, computational results and analysis demonstrated that there were two kinds of electronic extraction channel in the ECR neutralizer. One was affected by the potential well between magnetic well and anode, another was affected by the valley potential of electronic double sheath. The property of these two electronic extraction channels determined the variation of extracted electron current and mode conversion voltage.