FEL BEAM QUALITIES AND APPLICATION RESEARCHES AT THE FELI

Abstract The FELI four FEL facilities (FEL-1, FEL-2, FEL-3 and FEL-4) are open for users to supply several MW-level FELs covering a wide wavelength range from 278 nm to 40 μm. The ultraviolet (UV)- and visible-FEL facility (FEL-3) keeps the world record for the shortest wavelength oscillation of linac-based FELs with a thermionic gun since 1995. Technical challenges have been tried at simultaneous FEL beam sharing with fan-shaped mirrors for multistations including two manipulators and at FEL beam diagnostics of micropulse length and beam profile. The latter is for the evaluations of FEL peak power densities at irradiated spots. FEL peak power densities and adequate wavelengths are evaluated at thirteen research subjects performed at the FELI. The application researches have been performed distributed in a wide field of material science, chemical technology and bio-medical applications.