亚暴事件中磁尾多重等离子体团的数值研究(Ⅱ)  

SIMULATION STUDY OF MULTIPLE PLASMOIDS IN THE MAGNETOTAIL DURING SUBSTORM EVENT(Ⅱ)

作　　者：金曙平[1] 马宁[1] 胡先鹏[1] 宗秋刚[2] B.Wilken 刘振兴[2] 濮祖荫[4] 

机构地区：[1]中国科学技术大学地球与空间科学系 [2]中国科学院空间科学与应用研究中心,北京100080 [3]Max-Planck-InstitutfurAeronomie [4]北京大学地球物理系,北京100871

出　　处：《地球物理学报》1998年第5期609-620,共12页Chinese Journal of Geophysics

基　　金：国家自然科学基金

摘　　要：以宁静磁尾平衡解为初态，本文考虑介质的可压缩性，对GEOTAIL卫星于亚暴事件中，观测到多重等离子体团与高能离子爆相对应之特征作模拟研究．数值结果表明：重复形成的等离子体团是高温、高密度区，揭示了等离子体团与高能离子爆──对应的动力学原因．本文的模拟结果还表明：大尺度等离子体团的地向运动，与X中性点的尾向迁移及地向流动增强相对应，而上述现象与驱动入流沿着边界的分布形态（即电场E的分布）有关．In this paper, it is numerically investigared on the basis of initial tail like equlibrium configuration and 2D compressible MHD code that the multiple plasmoids observed by the GEOTAIL spacecraft are associated with energetic ion bursts. The numerical results illustrate that the plasmoids formed repeatedly are all high-temperature and large-density regions in comparison with the ambient environment. Such configurations are the indication of dynamic signature that the energehc ion bursts are associated with the plasmoid-like structures. As shown in the numerical results, the earthward convection of a larger-scale plasmoid is almost accompanied by tailward remove of the X neutral point and strengthened earthward flow. The phenomena might be related to the distributive pattern of imposing plasma inflow at the boundary (namely, the distributive pattem of electrical field E).

关 键 词：亚暴事件 等离子体团 高能离子爆 地向运动 

分 类 号：P352.4[天文地球—空间物理学]