ANGEO Annales Geophysicae ANGEO Ann. Geophys. 1432-0576 Copernicus Publications Göttingen, Germany 10.5194/angeo-24-3547-2006 Energetic ion injection and formation of the storm-time symmetric ring current Xie L. 1 Pu Z. Y. 1 Zhou X. Z. 1 Fu S. Y. 1 Zong Q.-G. 2 Hong M. H. 3 School of Earth and Space Sciences, Peking University, Beijing, 100871, China Center for Space Physics, Boston University, Boston, 02215, USA Institute of Geology and Geophysics, Chinese Academy of Science, 100029, China 21 12 2006 24 12 3547 3556 Copyright: © 2006 L. Xie et al. 2006 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://angeo.copernicus.org/articles/24/3547/2006/angeo-24-3547-2006.html The full text article is available as a PDF file from https://angeo.copernicus.org/articles/24/3547/2006/angeo-24-3547-2006.pdf

An extensive study of ring current injection and intensification of the storm-time ring current is conducted with three-dimensional (3-D) test particle trajectory calculations (TPTCs). The TPTCs reveal more accurately the process of ring current injection, with the main results being the following: (1) an intense convection electric field can effectively energize and inject plasma sheet particles into the ring current region within 1–3 h. (2) Injected ions often follow chaotic trajectories in non-adiabatic regions, which may have implications in storm and ring current physics. (3) The shielding electric field, which arises as a consequence of enhanced convection and co-exists with the injection and convection electric field, may cause the original open trajectories of injected ions with higher energy to change into closed ones, thus playing a role in the formation of the symmetric ring current.

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