Wen Wang¹, Liu Yang¹, Linghua Wang¹, Liang Zhao², Jiawei Tao¹, Gang Li³, Robert F Wimmer-Schweingruber⁴ and Stuart D Bale⁵, (1)Peking University, Beijing, China, (2)University of Michigan, Ann Arbor, MI, United States, (3)University of Alabama in Huntsville, Huntsville, AL, United States, (4)University of Kiel, Institute for Experimental and Applied Physics, Kiel, Germany, (5)University of California, Berkeley, Space Sciences Laboratory, Berkeley, CA, United States