Testing and benchmarking of a novel resistive wall boundary condition in the presence of an intense relativistic electron beam

Summary form only given, as follows. We report on a novel boundary condition, implemented in the parallel 3-D ICEPIC, that uses surface losses to mimic energy lost to the finite conductivity walls of a structure. This is especially important for cavities where diffraction losses do not dominate the resistive losses in the determination of the cavity quality factor Q. Since the losses are introduced only at the surface of the device, there are substantial savings of computational resources over volumetric approaches for 3-D simulations. This work is motivated by the observation that it is critical to match the simulated cold Q of an HPM tube to the experimental value to accurately model the behavior of the source with the beam present. This is true despite the fact that the IREB typically loads the cavity hot Q to a value much lower than the cold Q. Using the relativistic klystron oscillator as our test case, we investigate the performance of the new boundary condition in modeling the experimental cold tube results. We then report on the performance of the algorithm with the electron beam present.