*Kei Masunaga¹, Kanako Seki¹, David Brain², Xiaohua Fang², Yaxue Dong², Bruce Jakosky², James McFadden³, Jasper Halekas⁴, Jack Connerney⁵ (1.Department of Earth and Planetary Science, Graduate School of Science, University of Tokyo, Japan, 2.Laboratory for Atmospheric and Space Physics, University of Colorado Boulder, USA, 3.Space Science Laboratory, University of California Berkeley, USA, 4.Department of Physics and Astronomy, University of Iowa, USA, 5.NASA Goddard Space Flight Center, USA)