High-gain, high-power free electron lasers.

摘要

The Paladin FEL experiment is shown to exhibit clear and dramatic effects governed by the electron beam velocity distribution for the first time. The FEL integral equation is used to show that there is significant broadening of the gain spectrum due to the Gaussian velocity distribution, and also shows a plateau in the gain evolution along the undulator due to a triangular-shaped velocity distribution. The gain spectra and power evolution from simple, single- mode simulations are compared to the ELF experiments. The microwave power evolution along the undulator is compared as well for both the tapered and untapered undulators. In all cases, the agreement is found to be good.