Numerical simulation of electron-beam «squeezed» state in purpose to study the possibility of effective plasma frequency increase

Three-dimensional electromagnetic numerical simulation is carried out of «squeezed» state of the electron beam in two-section vircator system with drift tubes of different diameters. We have studied the influence of two-section system geometric parameters on the nonlinear dynamics of electron beam. We have obtained an effective plasma frequency depending on the system parameters. From the calculated dependencies it can be concluded that the density of the beam and the effective plasma frequency can be increased more than twice relative to the system without the formation of the «squeezed» state.