Construction and development of a UV free electron laser under the cooperation of Nihon U, KEK, PNC, ETL and Tohoku U

The construction and the development of a UV free electron laser have been started under the cooperation of Nihon U, KEK, PNC, ETL and Tohaku U. The project requires a 100MeV S-band electron linear accelerator to expand the oscillation of FEL using fundamental mode to the UV region. The injection system consists of a thermionic RF-gun with a LaB cathode and an α magnet for magnetic bunching. We are studying to reduce the back-bombardment electrons to realize the macropulse length of 20μsec. Electron beams, up to the energy of 100MeV, are injected into the optical oscillators. Changing the accelerating energy and/or undulator parameters, this system will cover the range from infrared to ultraviolet for the applications in various fields