Electromagnetic and thermal simulations for the switch region of a compact proton accelerator

A compact proton accelerator for medical applications is being developed at Lawrence Livermore National Laboratory. The accelerator architecture is based on the dielectric wall accelerator (DWA) concept. One critical area to consider is the switch region. Electric field simulations and thermal calculations of the switch area were performed to help determine the operating limits of silicon carbide (SiC) switches. Different geometries were considered for the field simulation including the shape of the thin indium solder meniscus between the electrodes and SiC. Electric field simulations were also utilized to demonstrate how the field stress could be reduced. Thermal simulations results were analyzed to find the average power capability of the switches.