Influence of microwave parameters on the xenon afterglow beam currents of a superconducting electron cyclotron resonance ion source

Heavy ion synchrotron accelerators rely on intense pulsed beams of highly charged ions. The production of these pulsed beams from an electron cyclotron resonance (ECR) ion source is predominantly achieved through the afterglow mode. However, the influence of microwave parameters on the characteristics of afterglow beams in high-frequency, high-power, and large plasma-volume ion sources remains unexplored. Recently, a series of experiments have been conducted with a third-generation superconducting ECR ion source. The effects of key microwave parameters, including the power level and pulse length of the secondary microwave source, as well as the RF-off time of the primary microwave radiation, on xenon afterglow beam currents are systematically examined. The experimental results and conclusions derived from the data are presented in this article.