Modeling Instabilities in Relativistic Electronic Beams in the CST Particle Studio Environment

Abstract

The paper is devoted to the development of the classical vircator model in the CST Particle Studio for the investigation of the physical mechanisms of the development, coexistence, and interaction of Pierce/Bursian and diocotron instabilities in relativistic electronic streams. Such a model is numerically analyzed by the CST Particle Studio. We find that a numerical instability develops, which leads to an additional small-scale space density modulation in the electron beam during its motion in the system. We find the character time scale of the instability and determine its relation with a spatial mesh step. We study the instability in detail and propose a method to suppress it by the CST Particle Studio. Also, important notes concerning the development of models of microwave devices in the CST Particle Studio are presented.