Gyrotron electron gun and collector simulation with the ESRAY beam optics code

The KIT two-dimensional beam optics code ESRAY is an efficient tool for the design and optimization of magnetron injection guns and collectors of gyrotrons or comparable vacuum tubes. The applied numerical methods and latest modifications and enhancements will be presented. To achieve more realistic results, a new emitter surface roughness model and the treatment of secondary electrons has been implemented recently. An extension to three dimensions (without taking space-charge effects into account) permits the simulation of various collector sweeping concepts, including the very efficient transverse sweeping.