1. School of Space and Environment Beihang University Beijing China
2. Department of Physics and Astronomy West Virginia University Morgantown West Virginia USA
3. Laboratory for Atmospheric and Space Physics University of Colorado at Boulder Boulder Colorado USA
4. Space Research Laboratory Democritus University Xanthi Greece
5. Swedish Institute of Space Physics Uppsala Sweden
6. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China
7. School of Space Science and Physics Shandong University Weihai China