Simulation of Electron Beam Acceleration by Electromagnetic Field in Static Inhomogeneous Magnetic Field

An autoresonance relativistic motion of 0.1 mA electron beam in a combined steady-state inhomogeneous magnetic field and a stationary microwave field is studied. The space profile of the axially symmetric magnetic field is fitted to maintain the interaction of electrons with the microwave field of cyclotron resonance type on all their trajectories. The Newton-Lorentz equation is simulated simultaneously with the Poisson equation by using the particle-in-cell method with the Boris leap-frog procedure and the Fast Fourier transform respectively. It is shown that the beam electrons can be accelerated up to 0.23 MeV by 2.45 GHz microwave field of TE112 mode and 0.85 MeV by the 100 MHz TE111 standing mode. In either case the amplitude of the microwave electric component is taken equal to 6 kV/cm.