Author: Kuroda, R.
Paper Title Page
MIR-FEL Oscillator Lasing by Photocathode Operation of LaB6 Thermionic Cathode in KU-FEL  
  • H. Zen, T. Kii, K. Masuda, H. Ohgaki, S. Suphakul
    Kyoto University, Kyoto, Japan
  • R. Kuroda, Y. Taira
    AIST, Tsukuba, Ibaraki, Japan
  Kyoto University Free Electron Laser (KU-FEL) is an oscillator type mid-infrared FEL having the tunable wavelength range from 5 to 22 micro-m [1]. The first lasing and power saturation of the facility using a 4.5-cell RF gun with a LaB6 thermionic cathode has been achieved in 2008 by overcoming the severe back-bombardment effect in the RF gun [2,3]. For upgrading the FEL performance, a multi-bunch picosecond mode-locked laser has been developed for driving a photocathode in the RF gun [4]. In February 2015, we have achieved first lasing of KU-FEL with photocathode operation of the LaB6 cathode in the 4.5-cell RF gun. The micro-pulse energy of the FEL at the wavelength of 11.7 micro-m with the photocathode operation was around 6.5 times as high as that with the thermionic cathode operation without any other modification of the FEL system. The performance of KU-FEL in the photocathode operation mode and comparison with the thermionic cathode operation will be presented in the conference.
[1] H. Zen, et al., Proc. of FEL2013, p.711, 2013
[2] H. Ohgaki, et al., JJAP, 47, p.8091, 2008
[3] H. Ohgaki, et al., Proc. of FEL08, p.4, 2008
[4] H. Zen, et al., Proc. of FEL2014, p.828, 2015
slides icon Slides MOA01 [1.347 MB]  
Export • reference for this paper to ※ LaTeX, ※ Text, ※ IS/RefMan, ※ EndNote (xml)