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arXiv · 2410.17304

Corotation-bounce resonance of ions in Jupiter's magnetosphere

Y. Sarkango·J. R. Szalay·P. A. Damiano·A. H. Sulaiman·P. A. Delamere·J. Saur·D. J. McComas·R. W. Ebert·F. Allegrini
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Abstract

Banded energy distributions of H$^{+}$, O$^{++}$, S$^{+++}$, and O$^+$ or S$^{++}$ ions between 100 eV to ~20 keV are consistently observed in Jupiter's magnetosphere mapping to M-shells between M=10-20. The bands correspond to flux enhancements at similar speeds for different ion species, providing the first evidence of simultaneous bounce-resonant acceleration of multiple ion species in Jupiter's magnetosphere. Ion enhancements occur for energies at which the bounce frequencies of the trapped ions matched integer harmonics of the System-III corotation frequency. The observations highlight a previously unknown interaction between corotation and bounce motion of <10 keV energy ions that is a fundamental and persistent process occurring in Jupiter's magnetosphere.

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Y. Sarkango, J. R. Szalay, P. A. Damiano, A. H. Sulaiman, P. A. Delamere, J. Saur, D. J. McComas, R. W. Ebert, F. Allegrini. 2024-10-22. Corotation-bounce resonance of ions in Jupiter's magnetosphere. https://doi.org/10.1029/2024gl113193

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