Simulation of Superradiant Free-Electron Lasers

摘要

It has been suggested that slippage effects in a single-pass free- electron laser can generate an output signal near the electron beam tail with a peak amplitude many times greater than the expected saturated value. The growth of such ''superradiant'' pulses in a helical-wiggler FEL is characterized here using 1-D and 2-D numerical simulations. The 1-D calculations show the effects of detuning, energy spread, and the axial current distribution on superradiant pulses, while preliminary 2-D simulations illustrate the effects of betatron motion and the radial structure of the electron beam. 12 refs., 6 figs., 1 tab. (ERA citation 14:015664)