Gyrotron heating of vacuum arc plasma for high charge state metal ion beam generation

High charge state heavy metal ion beams have been formed by high power microwave heating of vacuum arc plasma confined in magnetic traps. Two types of magnetic traps were investigated, one a simple mirror configuration and the other a cusp configuration with inherent “minimum-B” structure. Pulsed high power (>;100 kW) gyrotrons with frequency 37.5 GHz and 75 GHz were used for heating the vacuum arc plasma injected into the traps. Two different approaches were used for injecting the metal plasma - axial injection from a miniature arc source located on-axis near the microwave window, and radial injection from sources mounted radially at the midplane of the trap. High charge state heavy metal ion beams were extracted from the heated plasma.