Effects of a weak transverse magnetic field on negative ion transport in negative ion sources

A two-dimensional (2D) electrostatic particle simulation was performed to study the effects of a weak magnetic field on H- extraction. The motion of charged particles in their self-consistent electric field was simulated by a particle-in-cell model. The electrons are deflected by the weak magnetic field. H-ions arrive in the region close to the plasma grid in order to ensure plasma neutrality. The weak magnetic fields produces important modifications in positive ion flow and in the structure of the spatial potential which collects H-ions.