In situ evidence of the modification of the parallel propagation of EMIC waves by heated He <sup>+</sup> ions

TitleIn situ evidence of the modification of the parallel propagation of EMIC waves by heated He + ions
Publication TypeJournal Article
Year of Publication2016
AuthorsYuan, Z, Yu, X, Wang, D, Huang, S, Li, H, Yu, T, Qiao, Z, Wygant, JR, Funsten, HO
JournalJournal of Geophysical Research: Space Physics
Date Published07/2016
KeywordsEMIC waves; He+ ion heating; Ring current ions; stop band; Van Allen Probes
AbstractWith observations of the Van Allen Probe B, we report in situ evidence of the modification of the parallel propagating electromagnetic ion cyclotron (EMIC) waves by heated He+ ions. In the outer boundary of the plasmasphere, accompanied with the He+ ion heating, the frequency bands of H+ and He+ for EMIC waves merged into each other, leading to the disappearance of a usual stop band between the gyrofrequency of He+ ions (ΩHe+) and the H+ cutoff frequency (ωH+co) in the cold plasma. Moreover, the dispersion relation for EMIC waves theoretically calculated with the observed plasma parameters also demonstrates that EMIC waves can indeed parallel propagate across ΩHe+. Therefore, the paper provides an in situ evidence of the modification of the parallel propagation of EMIC waves by heated He+ ions
URLhttp://doi.wiley.com/10.1002/2016JA022573
DOI10.1002/2016JA022573
Short TitleJ. Geophys. Res. Space Physics


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