Van Allen Probes Bibliography is from August 2012 through September 2021 Notice:
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Dynamic Properties of Particle Injections Inside Geosynchronous Orbit: A Multisatellite Case Study
Author | Motoba, T.; Ohtani, S.; Claudepierre, S.; Reeves, G.; Ukhorskiy, A; Lanzerotti, L.; |
Keywords | deep particle injections; dipolarizations; substorms; localized DF; Van Allen Probes |
Abstract | Four closely located satellites at and inside geosynchronous orbit (GEO) provided a great opportunity to study the dynamical evolution and spatial scale of premidnight energetic particle injections inside GEO during a moderate substorm on 23 December 2016. Just following the substorm onset, the four spacecraft, a LANL satellite at GEO, the two Van Allen Probes (also called “RBSP”) at ~5.8 RE, and a THEMIS satellite at ~5.3 RE, observed substorm-related particle injections and local dipolarizations near the central meridian (~22 MLT) of a wedge-like current system. The large-scale evolution of the electron and ion (H, He, and O) injections was almost identical at the two RBSP spacecraft with ~0.5 RE apart. However, the initial short-timescale particle injections exhibited a striking difference between RBSP-A and -B: RBSP-B observed an energy dispersionless injection which occurred concurrently with a transient, strong dipolarization front (DF) with a peak-to-peak amplitude of ~25 nT over ~25 s; RBSP-A measured a dispersed/weaker injection with no corresponding DF. The spatiotemporally localized DF was accompanied by an impulsive, westward electric field (~20 mV m−1). The fast, impulsive E × B drift caused the radial transport of the electron and ion injection regions from GEO to ~5.8 RE. The penetrating DF fields significantly altered the rapid energy- and pitch angle-dependent flux changes of the electrons and the H and He ions inside GEO. Such flux distributions could reflect the transient DF-related particle acceleration and/or transport processes occurring inside GEO. In contrast, O ions were little affected by the DF fields. |
Year of Publication | 2020 |
Journal | Journal of Geophysical Research: Space Physics |
Volume | 125 |
Number of Pages | e2020JA028215 |
Section | |
Date Published | 09/2020 |
ISBN | |
URL | https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2020JA028215 |
DOI | https://doi.org/10.1029/2020JA028215 |