|Development of Photocachode Drive Laser System for RF Guns in KU-FEL
Funding: This research was supported by ZE Research Program, IAE, Kyoto University (ZE26A-22).
We have been developing an accelerator based infrared light sources at Institute of Advanced Energy, Kyoto University. An MIR-FEL has been developed* and a THz-FEL is under development**. A thermionic RF gun has been used as the electron source of MIR-FEL. A project of photocathode upgrade of the current thermionic RF gun is now undergoing to increase the peak power of the FEL. We need to develop multi-bunch laser for this purpose. On the other hand, the THz-FEL will be a single-pass FEL using an S-band 1.6-cell photocathode RF gun. For this purpose, a single-bunch laser is enough. A photocathode drive laser system for those purposes has been developed. The laser system consists of an Nd:YVO4 mode-locked oscillator with an integrated AOM, a laser pointing stabilizer, two diode pumped Nd:YAG amplifiers, and harmonic generators. In case of single-bunch operation of the laser, the pulse energy of higher than 150 micro-J at 266 nm has been obtained. For multi-bunch operation, 70 micro-J/micro-pulse and 70 pulses have been obtained. Optimization for multi-bunch operation of the laser is under going. In the conference, status of development of the drive laser will be presented.
*H. Zen, et al., Infrared Physics & Technology, vol. 51, pp.382-385 (2008).
**S. Suphakul, et al., in this conference.