Dynamics of the Magnetotail

该项目计划利用1992年7月发射的GEOTAIL宇宙飞船的数据，支助关于磁轨动力学的合作研究。在GEOTAIL任务的第一阶段，在两年的时间里，使用了双月球摆动技术来保持航天器在地球背面和月球以外的高度。在第一阶段获得的数据基础上，课课组的研究重点集中在等离子体和通量绳的结构、深尾的大尺度结构、慢模激波的识别、磁亚暴过程中等离子体的发展和传播、深尾的等离子体波等方面，报道了等离子体片边界层中非线性静电BGK模式波的存在以及叶区冷离子束的存在等新特征。其中一个重要的课题是通过高分辨率等离子体测量确定了可能与x型重联有关的慢模激波。为了有效地开展合作研究，与美国的合作研究人员举行了两次会议，并举行了专题研讨会。GEOTAIL观测的初步结果以35篇论文的形式发表在《地球物理研究快报》1994年12月15日的专刊上。这项合作研究的部分内容将发表在《j .地磁学与地电学》杂志的空间专刊上。

This project was planned to support cooperative studies on the dynamics of the magnetorail by using data from the GEOTAIL spacecraft, launched in July, 1992. In the first phase of the GEOTAIL mission, the double lunar swingby technique was used to keep the apogce of the spacecraft on the nightside of the earth and beyond the moon during two years. Based on data obtained during the first phase, studies of research groups have been focused on structures of plasmoid and flux ropes, large-scale structure of the deep tail, identification of slow-mode shock waves, development and propagation of plasmoids during magnetic substorms, plasma waves in the deep tail, etc..Several new features, such as the existence of the nonlinear electrostatic BGK mode wave in the plasma sheet boundary layr and cold ion beams in the lobe region, are reported. One of important topics is that slow-mode shock waves probably associated with the X-type reconnection were identified by high resolution plasma measurement.To proceed cooperative research effectively, two meetings were held with co-rescarchers from the U.S.A.as well as workshops on special topics. Initial results from the GEOTAIL observation were published as 35 papers in special section of Geophysical Research Letters (December 15,1994 issue). Part of this cooperative research will be published in a spacial issue of J.Geomagnetism and Geoelectricity for the magnetotail.