1. Department of Aeronautics and Astronautics, Graduate School of Engineering, the University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
2. Department of Advanced Energy, Graduate School of Frontier Sciences, the University of Tokyo, Kashiwa, Chiba 277-8561, Japan
3. Aerospace Research and Development Directorate, Research Unit III, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa 252-5210, Japan