中近磁尾等离子体片统计特性研究  

A statistical study of the plasma sheet in the near and middle earth magnetotail

作　　者：张帅[1] 田安民[1] 史全岐[1] 孙为杰[2] 尧中华[3] 傅绥燕[2] 宗秋刚[2] 濮祖荫[2] 

机构地区：[1]山东省光学天文与日地空间环境重点实验室空间科学与物理学院山东大学(威海),山东威海264209 [2]北京大学地球与空间科学学院,北京100871 [3]英国伦敦大学学院穆拉德空间科学实验室

出　　处：《地球物理学报》2016年第2期411-418,共8页Chinese Journal of Geophysics

基　　金：国家自然科学基金(41031065;41322031;41304129;41404131;41404117);山东省优秀中青年基金(2013BSE27132;BS2013HZ001);高等学校博士学科点专项科研基金(20130131120073);中国博士后科学基金资助项目(2014M561914)资助

摘　　要：本文使用Cluster-C1卫星的CIS仪器和FGM仪器测量得到的质子通量数据和计算的β数据,判断Cluster卫星在地球磁尾不同位置位于等离子体片内的概率.使用2001—2004年7—11月的Cluster-C1数据,分别在行星际磁场南向和北向时,得出X<-10RE区域内卫星位于等离子体片的概率在Y-Dz平面的分布图(Dz是卫星到中性片的距离).通过对比行星际磁场南向和北向时的卫星位于等离子体片的概率的分布图,我们发现等离子体片在行星际磁场南向时比在行星际磁场北向时要薄,并且这个效应在磁尾晨昏两侧比在午夜附近明显,同时我们还发现等离子体片在晨侧比在昏侧厚.Magnetotail plasma sheet is the most active area in Earth′s magnetosphere.It has been found that the features of plasma sheet are controlled by the conditions of Solar wind and Interplanetary Magnetic Field（IMF）.Some previous statistical studies have found that some parameters of the plasma sheet are dawn-dusk asymmetric.But the thickness of the magnetotail plasma sheet near the Cluster spacecraft orbit and how they are influenced by the IMF is still unclear.In this paper,the probability of the Cluster-C1 satellite encountering the plasma sheet is examined statistically by utilizing the proton flux andβdata from the CODIF and FGM equipment on board the Cluster-C1.Using data from July to November of year 2001—2004,the distributions of the probability of the satellite in the plasma sheet are mapped on the Y-Dz plane（Dzdenotes the distance from the neutral sheet）during the southward and northward IMF periods,respectively.By comparison,we found that the plasma sheet is thinner during southward IMF periods than that during northward IMF periods.It is more obvious in the flank regions of the plasma sheet.We also found that the plasma sheet in the dusk side is thinner than that in the dawn side.

关 键 词：质子通量 行星际磁场 晨昏不对称 

分 类 号：P353[天文地球—空间物理学]