Substorm current wedge composition by wedgelets

doi:10.1002/2015GL063289

CORC > 北京大学 > 地球与空间科学学院

	Substorm current wedge composition by wedgelets
	Liu, Jiang ; Angelopoulos, V. ; Chu, Xiangning ; Zhou, Xu-Zhi ; Yue, Chao
刊名	geophysical research letters
	2015
DOI	10.1002/2015GL063289
英文摘要	Understanding how a substorm current wedge (SCW) is formed is crucial to comprehending the substorm phenomenon. One SCW formation scenario suggests that the substorm time magnetosphere is coupled to the ionosphere via 'wedgelets,' small building blocks of an SCW. Wedgelets are field-aligned currents (FACs) carried by elemental flux transport units known as dipolarizing flux bundles (DFBs). A DFB is a magnetotail flux tube with magnetic field stronger than that of the ambient plasma. Its leading edge, known as a 'dipolarization front' or 'reconnection front,' is a product of near-Earth reconnection. Dipolarizing flux bundles, and thus wedgelets, are localized - each is only E wide. How these localized wedgelets combine to become large-scale (several hours of magnetic local time) region-1-sense SCW FACs is unclear. To determine how this occurs, we investigated wedgelets statistically using Time History of Events and Macroscale Interactions during Substorms (THEMIS) data. The results show wedgelet asymmetries: in the dawn (dusk) sector of the magnetotail, a wedgelet has more FAC toward (away from) the Earth than away from (toward) the Earth, so the net FAC is toward (away from) the Earth. The combined effect of many wedgelets is therefore the same as that of large-scale region-1-sense SCW, supporting the idea that they comprise the SCW. Key Points Each dipolarization front (DF) carries asymmetric field-aligned currents (FACs) The net FAC of a DF in tail's dawn (dusk) sector is toward (away from) the Earth Many DFs together produce the region-1-sense FAC of a substorm current wedge ?2015. American Geophysical Union. All Rights Reserved.; SCI(E); EI; 0; ARTICLE; jliu@igpp.ucla.edu; 6; 1669-1676; 42
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/329175]
专题	地球与空间科学学院
推荐引用方式 GB/T 7714	Liu, Jiang,Angelopoulos, V.,Chu, Xiangning,et al. Substorm current wedge composition by wedgelets[J]. geophysical research letters,2015.
APA	Liu, Jiang,Angelopoulos, V.,Chu, Xiangning,Zhou, Xu-Zhi,&Yue, Chao.(2015).Substorm current wedge composition by wedgelets.geophysical research letters.
MLA	Liu, Jiang,et al."Substorm current wedge composition by wedgelets".geophysical research letters (2015).