1. CAS Key Laboratory of Geospace Environment, Department of Geophysics and Planetary Sciences University of Science and Technology of China Hefei China
2. Collaborative Innovation Center of Astronautical Science and Technology University of Science and Technology of China Hefei China
3. Mengcheng National Geophysical Observatory, School of Earth and Space Sciences University of Science and Technology of China Hefei China
4. Department of Physics University of Texas at Dallas Richardson Texas USA