3D Configuration of Anti-parallel and Component Reconnection: Reconstruction of Cluster
作者单位：北京大学地球与空间科学学院 北京大学物理学院
会议名称：《第十四届全国日地空间物理学术研讨会》
会议日期：2011年
学科分类：070802[理学-空间物理学] 07[理学] 0708[理学-地球物理学]
摘 要：Magnetic reconnection （MR） has been commonly studied in two dimensional geometry and usually classified into two categories: anti-parallel and component, the terminology widely used in magnetospheric physics. However, MR is three dimensional （3D） in nature. It is thus necessary to reveal the 3D configuration of anti-parallel and component reconnection in reality. In this presentation we study an event in the magnetotail by reconstructing the magnetic field structure in the MR region based on Cluster four spacecraft measurements. The details of the reconstruction approach can be found in He et al. （2008）. It is found that in the event both anti-parallel and component reconnection processes can be detected. The reconstruction shows that in both processes two fan surfaces can be identified and intersect to form a separator. The MR process takes place just on the separator line. In the plane locally perpendicular to the separator, the magnetic field lines display the X-type topology. In the component MR process observed, a null-pair appears at the two ends of the separator. The magnetic field magnitude is found significant in the middle of the separator. On the other hand in the anti-parallel MR process observed, the magnetic field magnitude of the separator is however very weak everywhere. In short, this study shows that the 3D separator MR model can be applied for both processes, i.e., both component and anti-parallel MR processes require a null pair. Component and anti-parallel configurations are just the local manifestations of the 3D separator MR process.