Ultraviolet free-electron laser driven by a high-brightness 45-MeV electron beam

Abstract

We report on experimental studies of an ultraviolet (UV) free-electron laser (FEL) oscillator driven by low-energy electrons from a radio-frequency linear accelerator. Previous UV FELs have been driven by 350--800-MeV electrons from storage rings. We verify the concept of driving an UV FEL with a low-energy, but high-current, low-emittance electron beam. This and other innovations allowed the FEL to lase at wavelengths from 369 to 380 nm using 45.9--45.2-MeV electrons, and to achieve a peak optical output power of 270 kW. The experimental results are in good agreement with simulations.