Anomalously strong scattering of spontaneously produced laser radiation in the first free-electron laser and study of free-electron two-quantum stark lasing in an electric wiggler with quantum-wiggler electrodynamics

摘要

We calculate the scattering cross section of an electron with respect to the spontaneously produced laser radiation in the first free-electron laser (FEL) with quantum-wiggler electrodynamics (QWD). The cross section is 10(16) times the Thomson cross section, confirming the results obtained by a previous analysis of the experimental data. A QWD calculation show that spontaneous emission in an FEL using only an electric wiggler can be very strong while amplification through net stimulated emission is practically negligible.