High-current ion beam from a moving plasma

Abstract

High‐current ion beams in the 10–20‐keV range are extracted from a moving plasma. Current densities up to 2.5 A/cm² are obtained at the plasma boundary, which is almost an order of magnitude larger than the Bohm current. Total currents of over 100 A are obtained from the plasma. Simple geometric focusing gives current densities ∼200 A/cm² at the focus.