Beam loading and phase motion of particles in the selfconsistent RF field of linac

The dynamics of a high intensity electron beam in the travelling wave structure is studied. The equation for a self-consistent RF field are devised in the more general case in which the series resistance, wave phase velocity and damping coefficient are slowly varying functions of the longitudinal co-ordinate. Stationary solutions of nonlinear equations for the RF field amplitude, bunched beam energy gain and phase are found. The recommendations to optimise the efficiency of low energy electron accelerator are discussed.