Altitude of the upper boundary of AAR based on observations of ion beams in inverted-V structures:A case study

作     者：CUI YanBo FU SuiYan ZONG QiuGang XIE Lun SUN WeiJie ZHAO Duo WU Tong George PARKS 

作者机构：School of Earthand Space SciencesPeking University Key Laboratory of Earth and Planetary PhysicsInstitute of Geology and GeophysicsChinese Academy of Sciences Space Sciences LaboratoryUniversity of CaliforniaBerkeley 

出 版 物：《Science China Earth Sciences》 (中国科学（地球科学英文版）)

年 卷 期：2016年第59卷第7期

页      面：1489-1497页

核心收录：

学科分类：070802[理学-空间物理学] 07[理学] 0708[理学-地球物理学] 

基　　金：supported by the National Natural Science Foundation of China (Grant Nos. 41031065, 41421003) by the Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences 

主　　题：Outflowing ion beams Inverted V structure Auroral acceleration region U shaped potential structure Altitude of upper boundary 

摘      要：Outflowing ion beams forming four successive inverted-V structures in the energy-time spectrograms of H+, He+, and O+ were observed at an altitude of 3.4 RE by Cluster satellites travelling above the auroral acceleration region (AAR) in the southern hemisphere on February 14, 2001. Energization by negative U-shaped potential structures in the AAR is believed to be responsible for the formation of these outflowing ion inverted-V structures. Thus, utilizing the different motion properties of the three ion species, the altitude of the upper boundary of the AAR is estimated to be ~11100 km. Moreover, based on multi-satellite observations, each of these U-shaped potential structures involved in this event crosses the latitudinal direction at ~0.4°–1° invariantlatitude (ILAT), moving poleward at an average speed of ~0.2° ILAT per minute, before disappearing at ~71.5° ILAT.