Development of ultra-violet femtosecond pulse radiolysis system based on a photocathode rf electron-gun linac

Two important radical species of alkyl radical (R·) and hydroxyl radicals (OH·) in nuclear fuel reprocessing or radiation cancer therapy have absorption bands around the 250 nm in Ultra-violet region. Despite the OH· and R· are important active species in the radiation chemistry, since those absorption coefficients are small and lack of time resolution of pulse radiolysis, a direct study of the reaction dynamics has been difficult until now. In order to elucidate the formation and reaction with solutes, measurable wavelength was extended to ultraviolet of the femtosecond pulse radiolysis system using a photocathode RF gun accelerator. Problems of ultraviolet femtosecond pulse radiolysis measurement, the time dependent behaviors of R· and OH· are reported. (author)