1. Data Analysis Center for Geomagnetism and Space Magnetism, Graduate School of Science; Kyoto University; Kyoto Japan
2. Applied Physics Laboratory; Johns Hopkins University; Laurel Maryland USA
3. Department of Earth and Planetary Sciences; Kyushu University; Fukuoka Japan
4. Graduate School of Science; Tohoku University; Sendai Japan
5. Department of Physics; University of York; York United Kingdom
6. Hermanus Magnetic Observatory; Hermanus South Africa
7. Office of Research and Development; National Space Development Agency of Japan; Tsukuba Japan
8. Graduate School of Science and Technology; Chiba University; Japan