1. Department of Astronomy, Graduate School of Science, Kyoto University , Sakyo, Kyoto 606-8502 , Japan
2. Department of Physics, Graduate School of Science, Kyoto University , Sakyo, Kyoto 606-8502 , Japan
3. Center for Computational Sciences, University of Tsukuba , Ten-nodai, 1-1-1 Tsukuba, Ibaraki 305-8577 , Japan
4. Department of Earth and Planetary Sciences, Tokyo Institute of Technology , Meguro, Tokyo 152-8551 , Japan