Experimental study of compact FEL with micro wiggler and electrostatic accelerator

(TU-5-01)

S.Fijii, H.Mori, T.Mizuno, T.Ohshima, M.Kawai, H.Saito, K.Koshiji  

Science University of Tokyo, Soka University, Institute of Space and Astronautical Science, Kawasaki Heavy Industries Ltd,

A compact FEL for submillimeter and far infrared region is studied at the Institute of Space and Astronautical Science, Japan. The FEL is composed of an electrostatic accelerator and a micro wiggler. Total length of the FEL instrument is about 2.5m. The electrostatic accelerator (DISKTRON) with a diameter of 1m can generate up to 1MV. The micro wiggler is fabricated using permanent magnets (period:8mm, length:248mm, gap:2-10mm, K: < 0.71). A high quality electron beam can be generated by means of a photoemissive cathode (700kV, 1.3A, 81A/cm², 1.6mm in diameter, dE/E < 0.18%). We plan to oscillate the FEL at 96GHz as a first step of the experiment. We apply a resonator with DBR (Distributed Bragg Reflector) in order to oscillate at 96GHz. Design of the resonator and result of the oscillation will be reported.