Investigation of the Effect of Residual Gas Ionization on Virtual Cathode Formation Processes

The paper presents the results of a study of the influence of plasma effects on processes occurring in systems of high-power electronics. The results are obtained using electromagnetic PIC code for a promising class of high-power microwave devices relativistic vircators (generators and amplifiers with a virtual cathode (VC)). A detailed study of the behavior of critical current of a relativistic electron beam (REB) with a change in the control parameters of the system (concentration of residual gases, external magnetic field parameters, energy of electron beam, and shape of current pulse) is carried out. The results obtained within the framework of the research are intended to broaden the fundamental concepts about the dynamics of intense electron beams in a plasma.