The relationship between the magnetic cloud boundary layer and the substorm expansion phase

	The relationship between the magnetic cloud boundary layer and the substorm expansion phase
	Zuo, P. B. ; Wei, F. S. ; Feng, X. S. ; Yang, F
刊名	Solar Physics
	2007
卷号	242 期号:40180 页码:167-185
关键词	inter-planetary shock solar-wind magnetospheric substorms ultraviolet imager events voyager maximum plasma fields helios
ISSN号	0038-0938
通讯作者	北京8701信箱
英文摘要	The magnetic cloud boundary layer (BL) is a disturbance structure that is located between the magnetic cloud and the ambient solar wind. In this study, we statistically analyze the characteristics of the magnetic field B (z) component (in GSM coordinates) inside the magnetic cloud boundary layers as well as the relationship between the magnetic cloud boundary layers and the magnetospheric substorms based on 35 typical BLs observed by Wind from 1995 to 2006. It is found that the magnetic field B-z components are more turbulent inside the BLs than those inside the adjacent sheath regions and the magnetic clouds. The substorm onsets are identified by the auroral breakups that are the most reliable substorm indicators by using the Polar UVI image data. The UVI data are available only for 17 BLs. The statistical analysis indicated that 9 of the 17 events triggered the substorms when BLs crossed the magnetosphere and that the southward field in the adjacent sheath region is a necessary condition for these triggering events. In addition, the SF-type BLs, which are named by their features of the B (z) components inside the BLs and adjacent sheath regions, can easily trigger the substorms during their passage of the magnetosphere. SF-type BLs are characterized by sustained strong southward magnetic fields persisting for at least 30 minutes in the adjacent sheath regions and at least one change in the polarity of the B (z) component inside the BL. In this study, 7 out of 8 such SF-type BL events triggered the substorm expansion phase, suggesting that the SF-type BLs are another important interplanetary disturbance source of substorms.
学科主题	空间物理
收录类别	SCI
原文出处	http://www.springerlink.com/content/c2vv23311jr08325/fulltext.pdf
语种	英语
内容类型	期刊论文
源URL	[http://ir.cssar.ac.cn/handle/122/1082]
专题	国家空间科学中心_空间科学部
推荐引用方式 GB/T 7714	Zuo, P. B.,Wei, F. S.,Feng, X. S.,et al. The relationship between the magnetic cloud boundary layer and the substorm expansion phase[J]. Solar Physics,2007,242(40180):167-185.
APA	Zuo, P. B.,Wei, F. S.,Feng, X. S.,&Yang, F.(2007).The relationship between the magnetic cloud boundary layer and the substorm expansion phase.Solar Physics,242(40180),167-185.
MLA	Zuo, P. B.,et al."The relationship between the magnetic cloud boundary layer and the substorm expansion phase".Solar Physics 242.40180(2007):167-185.