SATURNUS - THE UCLA HIGH-GAIN INFRARED FEL PROJECT

We present the status of Saturnus: an infrared FEL operating in the 10-mu-m wavelength region, driven by a compact 20 MeV linac with a photoinjector, under construction at UCLA. The 1.5 cm period, 0.5 T peak-field undulator is being built at the Kurchatov IAE. The FEL is being designed to operate primarily in the self-amplified spontaneous emission mode. We plan to study the startup from noise, optical guiding, saturation, sidebands and superradiance, with emphasis on the effects important for future short-wave-length operation of FELs. The photoinjector follows closely the Brookhaven design. Electrons are injected into an accelerating section based on the plane-wave transformer design developed by Swenson at SAIC. Simulation of the linac and FEL show a gain length of 10 cm, and saturation power of 50 MW.