Nonlinear analysis on electron beam current in cylindrical waveguide

Abstract

The space-charge-limited currents of both solid electron beam and annular electron beam in cylindrical waveguide are derived from the nonlinear Poisson equation for potential in the region of electron beams. Corrections for the transverse motion of electrons are made to the solution, which bring more consistent with the results from PIC simulations. Though numerical computation, it is showed that electrons located along the axis and by outer radius of solid and annular electron beams respectively and electrons standing near to the outside of the beam has larger axial velocity than these inside. This approach is available for analyzing the characteristics of electron beam transporting in high power microwave generator with other configuration waveguide.