1. Space Sciences Laboratory; University of California; Berkeley; California; USA
2. Solar Terrestrial Environment Laboratory; University of Nagoya; Nagoya; Japan
3. Graduate School of Science, Planetary Plasma and Atmospheric Research Center; University of Tohoku; Sendai; Japan
4. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency; Sagamihara; Japan
5. Department of Earth and Planetary Science, Graduate School of Science; University of Tokyo; Tokyo; Japan