Simulation and optimization of a negative hydrogen Penning ion source

摘要

The results of a Particle-In-Cell Monte-Carlo Collision simulation of a cold cathode Penning type ion source are presented. The source is designed to generate H- ions through the volume production process. Twenty-one important processes including electron and heavy particle collisions are introduced into the simulation. The main focus was the energy distribution of electrons which has a large effect on the H- production rate in the volume production. The dependence of the energy distribution of electrons on the axial magnetic field was investigated. The large sensitivity of the H- production rate to the energy distribution of electrons was measured. It was observed that for an anode with a 5 mm radius increasing the axial magnetic field in the range of 0.5-1.1 T results in the increase in the H- density almost by a factor of 14. In addition, it was found that the anode with a radius of 5 mm was the most efficient anode in H- production among the anodes with radii from 3 to 6 mm. Published by AIP Publishing.