DOI: 10.1029/2018JA025689
Scopus记录号: 2-s2.0-85052402635
论文题名: Oxygen Ion Reflection at Earthward Propagating Dipolarization Fronts in the Magnetotail
作者: Zhao S.J. ; Fu S.Y. ; Sun W.J. ; Parks G.K. ; Zhou X.Z. ; Pu Z.Y. ; Zhao D. ; Wu T. ; Yu F.B. ; Zong Q.G.
刊名: Journal of Geophysical Research: Space Physics
ISSN: 21699380
出版年: 2018
卷: 123, 期: 8 起始页码: 6277
结束页码: 6288
语种: 英语
英文关键词: dipolarization front
; flux dropout
; oxygen ions
; reflection process
英文摘要: A dipolarization front (DF) is known as the leading edge of an earthward high-speed flow with a sharp enhancement in the northward magnetic field (Bz). Analysis of an event observed by Cluster shows that the behavior of oxygen ions (O+) around the DF is very different from protons (H+). After the crossing of the DF, the O+ density decreases more gradually than H+. The distance between the density minimum of O+ and the DF layer is ~4 times longer than that of H+, which is close to their gyroradii ratio with the same energy. A flux dropout is observed in the O+ energy spectrum, whose energy dependence indicates that ions with higher energies can reach locations farther tailward of the DF. Similar variations are also seen in studies of 22 events in which a common pattern of ion properties is obtained by performing a superposed epoch analysis. Finally, using backward tracing test-particle simulations, we reproduce the characteristics of the flux dropout and verify that the time dependence of the dropout is highly correlated with the gyromotion of different energy O+ behind the DF. All these results provide a further understanding of ion dynamics associated with DFs and suggest that the observed O+ ions are reflected within a half gyromotion in the central plasma sheet. ©2018. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/113393
Appears in Collections: 气候减缓与适应
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作者单位: School of Earth and Space Sciences, Peking University, Beijing, China; Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China; Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, MI, United States; Space Sciences Laboratory, University of California, Berkeley, CA, United States
Recommended Citation:
Zhao S.J.,Fu S.Y.,Sun W.J.,et al. Oxygen Ion Reflection at Earthward Propagating Dipolarization Fronts in the Magnetotail[J]. Journal of Geophysical Research: Space Physics,2018-01-01,123(8)