Tohoku University, Tohoku University, Tohoku University, Saitama University, Japan Atomic Energy Agency, Tohoku University, Tohoku University, Tohoku University, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, Tohoku University, Tohoku University, Tohoku University, Kyoto University - Particle Radiation Oncology Research Center and Kyoto University - Particle Radiation Oncology Research Center