1. Department of Physics, The University of Tokyo, 7-3-1, Hongo, Bunkyo, Tokyo 113-0033, Japan
2. Kavli Institute for the Physics and Mathematics of the Universe (WPI), Institutes for Advanced Study (UTIAS), The University of Tokyo, 5-1-5 Kashiwa-no-Ha, Kashiwa, Chiba 277-8583, Japan
3. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo Sagamihara, Kanagawa 252-5210, Japan
4. Institute for Laser Science, The University of Electro-Communications, Chofu, Tokyo 182-8585, Japan
5. Komaba Institute for Science, The University of Tokyo, 3-8-1 Komaba, Meguro, Tokyo 153-8902, Japan
6. Department of Physics, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
7. RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan