1. Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China
2. College of Earth and Planetary Sciences University of Chinese Academy of Sciences Beijing China
3. Swedish Institute of Space Physics Kiruna Sweden
4. IRAP, CNRS‐UPS‐CNES Toulouse France
5. Now at Graduate School of Frontier Sciences The University of Tokyo Kashiwa Japan
6. Beijing International Center for Mathematical Research Peking University Beijing China
7. Princeton Plasma Physics Laboratory and Department of Astrophysical Sciences Princeton University NJ Princeton USA
8. Solar System Exploration Division NASA Goddard Space Flight Center MD Greenbelt USA