Relativistic klystron two-beam accelerator simulation code development

We present recent work on the development and testing of a 3-D simulation code for relativistic klystron two-beam accelerators (RK-TBAs). This code builds on our previous experience with 1-D and 2 1/2-D relativistic klystron simulators. We adopt a new approach utilizing symplectic integration techniques to push particles, coupled to a circuit equation framework that advances fields in the cavities. Space charge and current effects are calculated using an electrostatic PIC algorithm.