地球磁层极尖区场向电子事件期间能量特性研究  

Study on Energy Features during a Field-aligned Electron Events in the Cusp Region

作　　者：史建魁[1,2] 张子迎[3] TORKAR Klaus 王铮[1] 程征伟[1] 王国军[1] SHI Jiankui ZHANG Ziying TORKAR Klaus WANG Zheng CHENG Zhengwei WANG Guojun(State Key Laboratory of Space Weather, National Space Science Center, Chinese Academy of Sciences, Beijing 100190 University of Chinese Academy of Sciences, Beijing 100049 College of Applied Arts and Science, Beijing Union University, Beijing 100191 Space Research Institute, Austrian Academy of Sciences, Graz, Austria, A-8042)

机构地区：[1]中国科学院国家空间科学中心空间天气学国家重点实验室,北京100190 [2]中国科学院大学,北京100049 [3]北京联合大学应用文理学院,北京100191 [4]Space Research Institute,Austrian Academy of Sciences,Graz,Austria,A-8042

出　　处：《空间科学学报》2016年第6期849-856,共8页Chinese Journal of Space Science

基　　金：国家自然科学基金项目(41274146,41474137,41574150);国家重点实验室专项基金项目共同资助

摘　　要：根据Cluster卫星2001年9月30日在北半球极尖区观测到的一次强扰动场向电子事件数据,分析研究了这次事件期间场向电子的能量特性,讨论了场向电子对太阳风能量向磁层的传输和磁层-电离层耦合过程中能量传输的作用.分析认为,这次电子扰动事件期间电子速度和密度都具有很强的扰动变化,电子速度增加是一个主要特点.本次事件中低能段5~200 eV和500~1500 eV内的能谱分析结果表明,上行电子通量大于下行电子通量,上行电子主要来源于电离层,说明电离层上行电子在本次事件中具有非常活跃的作用.根据电离层中带电粒子的能量特征分析结果可知,这次事件中电离层起源的上行电子在上行过程中得到了加速.关于加速机制问题还有待深入研究.By focusing on an extremely disturbed field-aligned electrons event observed with Cluster in the northern cusp region on 30 September 2001,the energy features of the field-aligned electrons in the event is analyzed and the roles of the field-aligned electrons on the transmission of solar wind energy to the magnetosphere and on the magnetosphere-ionosphere coupling are discussed.The results show that the velocities and densities of the electrons have strong disturbances during the event,and the velocity is a main factor to enhance the electron flux.The electron energy spectrum in 5~200eV and 500~1500eV show that the up-flowing electron flux is higher than that of downflowing,which means the up-flowing electrons mainly come from the ionosphere and play an active role in this event.The energy features show that the ionospheric electrons have been accelerated during the up-flowing.However,the accelerating physical mechanism still needs to be further studied.

关 键 词：极尖区 场向电子 能量特性 电离层起源 

分 类 号：P353[天文地球—空间物理学]