Simulation of an axial vircator with a three-cavity resonator
  We simulated an axial vircator with a three-cavity resonator and expected generation efficiency 6-7 percents. For adequate description of physical processes taking place inside a vircator we used two independent PIC codes: self-developed INPIC and free XOOPIC. Based on both the analysis of the vircator proposed in [1] and consideration of the devices operating at cathode-anode voltages under 450 kV we suggest 3 possible designs of a three-cavity resonator such that enable one to produce High Power Microwave in GW power range. 
P.V. Molchanov, E.A. Gurnevich, V.V. Tikhomirov, S.E. Siahlo
physics.acc-ph