2001年1月26日高纬磁层顶通量管事件的观测研究——空间电流密度计算及分析  

MULTIPLE FLUX ROPE EVENTS AT THE HIGH-LATITUDE MAGNETOPAUSE ON JANUARY 26, 2001:CURRENT DENSITY CALCULATING

作　　者：肖池阶[1] 濮祖荫[1] 黄宗英[1] 傅绥燕[1] 谢伦[1] 宗秋刚 T Fritz K-H Glassmeier 刘振兴[4] 曹晋滨[4] 史建魁[4] 沈超[4] 路立[4] 王迺权[4] 陈涛[4] 

机构地区：[1]北京大学地球与空间科学学院,北京100871 [2]Center for Space Physics,Boston University [3]IGM,Technische University Braunschweig [4]中国科学院空间科学与应用研究中心,北京100080

出　　处：《地球物理学报》2004年第4期555-561,共7页Chinese Journal of Geophysics

基　　金：国家自然科学基金委重点项目 ( 4 983 40 40 );重大项目 ( 4 0 3 90 15 0 );国家重大基础科学项目 (G2 0 0 0 0 0 784)

摘　　要：讨论了三种根据ClusterⅡ四颗卫星的磁场测量数据计算空间电流的方法及其误差 ,论证了这几种方法的内在一致性 ,并得到了完全相同的计算结果 .进而依据ClusterⅡ磁场探测资料 ,计算了 2 0 0 1年 1月 2 6日多重磁通量管和FTE事件中高纬磁层顶边界层和磁鞘区的电流密度 .结果表明 ,磁通量管内电流密度较大 ,可达到约10 - 8A m2 ;计算精度较高 ,结果可靠 .本文还应用最小方差分析法 (MVA) ,发现电流方向与通量管的轴向基本一致 ;论证了电流MVA分析在研究通量管性质时的作用 。A systematic comparison is carried out for three Methods of current density calculating based on simultaneous magnetic field measurements of four-spacecraft Cluster mission. Analytically and numerically demonstrated that within the linear approximation, all these methods lead to the exactly the same results. As a case study, the current density of multiple flux rope events at the high-latitude magnetopause on January 26,2001 is investigated. It is showed that an intense current flows inside the ropes with the current density reaching as high as about 10 -8A/m 2. The current inside rope is valuable for the small relative calculating error. It is also found that the directory of current is almost parallel the axis of flux rope gotten by magnetic minimum variance analysis (MVA). It is supposed the current MVA method is useful and simply for the rope axis orientation.

关 键 词：电流密度 通量管 磁层顶 最小方差分析法 

分 类 号：P353[天文地球—空间物理学]