A numerical study on free-electron laser dynamics

Dynamics of Free-electron lasers(FEL) is investigated on the basis of the pendulum equations in the one-dimensional formulation. The phase-space evolution and the bunching coefficients of the electrons, which enable one to find the evolution of the radiation field, are briefly reviewed. Describing the computational procedures for solving the FEL pendulum equations numerically, we discuss the electron dynamics and the evolutions of the radiation field in the various gain regimes and the saturation regimes. Also we carried out numerical studies on the inhomogeneous broadening effects due to the energy spread and emittance of an electron beam