• T. Suzuki, T. Fujino, Y. Kato, A. Masuda, A. Murata, K. Sakaue, M. Washio
  RISE, Tokyo
• H. Hayano, T. Takatomi, N. Terunuma, J. Urakawa
  KEK, Ibaraki
• S. Kashiwagi
  ISIR, Osaka
• R. Kuroda
  AIST, Tsukuba, Ibaraki

At Waseda University, we have been developing a high quality electron source based on photo-cathode rf-gun and its application experiments. To produce a high current electron beam, we installed a Cs-Te cathode which has higher quantum efficiency and improved the structure of the rf cavity. By adopting a Cs-Te cathode, it is expected that the production of the higher charged single bunch electron beam with a low emittance can be achieved. Moreover, the generation of high quality multi-bunch electron beam is also expected to be possible due to the high quantum efficiency of Cs-Te. For understanding of a Cs-Te cathode and higher quantum efficiency operation, we have performed the fundamental studies by single bunch beam. On the other hand, we have also developed a multi-pulse UV laser for generating the multi-bunch electron beam. Our laser system is composed by all-solid-state Nd:YLF for the stable operation, and the specification of this laser is expected to generate a 100bunch/train with the bunch charge of 800pC/bunch. In this conference, the experimental results of Cs-Te and new laser system and the recent progress of multi-bunch electron beam generation will be reported.

• A. Fujita, Y. Hama, Y. Hosaka, T. Nomoto, K. Sakaue, M. Washio
  RISE, Tokyo
• S. Kashiwagi
  ISIR, Osaka
• R. Kuroda
  AIST, Tsukuba, Ibaraki
• K. Ushida
  RIKEN, Saitama

A pulse radiolysis method is very useful in clarifying primary processes of radiation chemistry. At Waseda University, compact pico-second and nano-second pulse radiolysis systems have been developing. A pico-second system is based on pump-probe method. IR and UV pico-second laser pulses are generated from Nd:YLF mode-locked laser and used for generating of white light continuum as analyzing light and irradiating to photo-cathode RF gun, respectively. Recently, we have installed a new photo-cathode RF gun with Cs-Te cathode which has high quantum efficiency, so we have succeeded in improving optical density and S/N ratio of our pulse radiolysis system. We are now developing a new nano-second system which can get time profile with only one-shot and follow up wider time region than pico-second system. In the past, this system has been used He-Ne laser as analyzing light, but it can measure only 633nm. Instead of He-Ne laser, this system adopts Xe flush lamp which has broad spectrum as analyzing light. As system evaluation experiments, we tried to get time profile of some species. In this conference, present status and future plans of our pulse radiolysis systems will be reported.