The influences of the magnetic field strength on the magnetic confinement of primary electrons in an ion source

This paper deals with the simulation of trajectories of energetic electrons under the influence of a multi-cusp magnetic field produced by a permanent magnet assembly in a ring cusp geometry which is designed for supporting a plasma based ion source. The primary electrons are assumed as being emitte d from a cathode located coaxially with the cylindrical discharge chamber. The volume of the region occupied by the electron trajectories and the magn etic trapping time were evaluated and plots are presented showing the effec ts of the surface magnetic field strength of the magnets on the volume and the mean confinement time of primary electrons in the ion source.