Radial Distribution of Charged Particle Concentrations in a Magnetic Ion Source

摘要

The results of some experiments on a magnetic ion source are presented. The results show that the increase of magnetic field is accompanied by the appearance of a main discharge column, the radius of which approaches the cathode radius. This column is a plasma pierced by the fast primary electrons. The law of the radial discharge distribution inside the column differs from that outside the column if the magnetic field is large enough. An equation is obtained for radial distribution of the charged particles concentration. It is based on the following assumption. Ionization is produced mainly by the fast primary electrons, but the neutralization of the positive space charge takes place chiefly because of the slow electrons. The electrons generated in the column leave it because of the radial diffusion weakened by the magnetic field influence. The ions produced in the column leave it chiefly along the 'potential groove' to the ends of the vessel.