Primary knock-on atoms for accelerator facilities; Simulations and experimental design

Tsai, P.-E.; Iwamoto, Yosuke   ; Hagiwara, Masayuki*

The importance of PKA characteristics to radiation damage assessment for proton accelerators has been demonstrated in the paper by the PHITS simulations. In order to obtain accurate results of displacement cross section calculated by PHITS, it is therefore critical to have the physics models implemented in PHITS be properly validated by experimental data. With the new measurement system, which has been being developed here at JAEA, it is expected to provide experimental PKA data with low measurement thresholds and good mass resolutions. The test result we obtained at CYRIC, Tohoku University, for the - gas ionization chamber as a part of the new measurement system was very promising. We were able to successfully distinguish C, B, Be, Li, and He elements with threshold energies lower than 1 MeV/nucleon in the configuration of 70-MeV proton beam and 920-nm thick C target. More experiments and tests shall continue in the future with heavier targets and higher proton beam energies.