Spatial distribution of Mercury&apos;s flux ropes and reconnection fronts:   MESSENGER observations

doi:10.1002/2016JA022787

CORC > 北京大学 > 地球与空间科学学院

	Spatial distribution of Mercury's flux ropes and reconnection fronts: MESSENGER observations
	Sun, W. J. ; Fu, S. Y. ; Slavin, J. A. ; Raines, J. M. ; Zong, Q. G. ; Poh, G. K. ; Zurbuchen, T. H.
刊名	JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
	2016
关键词	FIELD-ALIGNED CURRENTS PLASMA SHEET GEOTAIL OBSERVATIONS MAGNETIC-FIELD EARTH MAGNETOTAIL 3-DIMENSIONAL STRUCTURE AURORAL BRIGHTENINGS TRANSFER EVENTS SUBSTORM ONSET MAGNETOSPHERE
DOI	10.1002/2016JA022787
英文摘要	We perform a statistical study of flux ropes and reconnection fronts based on MErcury Surface, Space ENviroment, GEochemistry, and Ranging (MESSENGER) magnetic field and plasma observations to study the implications for the spatial distribution of reconnection sites in Mercury's near magnetotail. The results show important differences of temporal and spatial distributions as compared to Earth. We have surveyed the plasma sheet crossings between -2 R-M and -3 R-M downtail from the planet, i.e., the location of Near-Mercury Neutral Line (NMNL). Plasma sheets were defined to be regions with beta >= 0.5. Using this definition, 39 flux ropes and 86 reconnection fronts were identified in the plasma sheet. At Mercury, the distributions of flux ropes and reconnection fronts show clear dawn-dusk asymmetry with much higher occurrence rate on the dawnside plasma sheet than on the duskside. This suggests that magnetic reconnection in Mercury's magnetotail occurs more frequently in the dawnside than in the duskside plasma sheet, which is different than the observations in Earth's magnetotail showing more reconnection signatures in the duskside plasma sheet. The distribution of plasma sheet thickness shows that plasma sheet near the midnight is the thinnest part and does not show obvious asymmetry. Thus, the reasons that cause magnetic reconnection to preferentially occur on the dawnside of the magnetotail at Mercury may not be the plasma sheet thickness and require further study. The peak occurrence rates of flux ropes and reconnection fronts in Mercury's plasma sheet are similar to 60 times higher than that of Earth's values, which we interpret to be due to the highly variable magnetospheric conditions at Mercury. Such higher occurrence rate of magnetic reconnection would generate more plasma flows in the dawnside plasma sheet than in the duskside. These plasma flows would mostly brake and initiate the substorm dipolarization on the postmidnight sector at Mercury rather than the premidnight susbtorm onset location at Earth.; NASA [NASW-00002, NAS5-97271]; State Scholarship Fund of Chinese Scholarship Council; National Nature Science Foundation of China [41474139, 41421003]; NASA Heliophysics Supporting Research Program [NNX15AJ68G]; SCI(E); ARTICLE; weijiesun@pku.edu.cn; 8; 7590-7607; 121
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/458965]
专题	地球与空间科学学院
推荐引用方式 GB/T 7714	Sun, W. J.,Fu, S. Y.,Slavin, J. A.,et al. Spatial distribution of Mercury's flux ropes and reconnection fronts: MESSENGER observations[J]. JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS,2016.
APA	Sun, W. J..,Fu, S. Y..,Slavin, J. A..,Raines, J. M..,Zong, Q. G..,...&Zurbuchen, T. H..(2016).Spatial distribution of Mercury's flux ropes and reconnection fronts: MESSENGER observations.JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS.
MLA	Sun, W. J.,et al."Spatial distribution of Mercury's flux ropes and reconnection fronts: MESSENGER observations".JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS (2016).