*Harneet Kaur Sangha^1,2、S E Milan^1,3、B J Anderson⁴、H Korth⁴ (1.Univ. of Leicester, UK、2.Univ. of Alabama in Huntsville, US、3.Birkeland Centre for Space Science, Univ. of Bergen, Norway、4.Johns Hopkins Univ. Applied Physics Laboratory, US)