1. Department of Pure and Applied Physics, Kansai University, Suita, Osaka, Japan
2. Division of Sustainable Energy and Environmental Engineering, Graduate School of Engineering, Osaka University, Suita, Osaka, Japan
3. State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, P. R. China
4. Division of Biology, Radioisotope Research Center, Kyoto University, Sakyo-ku, Kyoto, Japan
5. Department of Radiation Biology and Medical Genetics, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan
6. Yukawa Institute for Theoretical Physics, Kyoto University, Sakyo-ku, Kyoto, Japan
7. Research Center for Nuclear Physics (RCNP), Osaka University, Ibaraki, Osaka, Japan