Ion Heating by Electromagnetic Ion Cyclotron Waves and Magnetosonic Waves in the Earth\textquoterights Inner Magnetosphere

Author
Keywords
Abstract
Electromagnetic ion cyclotron (EMIC) waves and magnetosonic waves are commonly observed in the Earth\textquoterights magnetosphere associated with enhanced ring current activity. Using wave and ion measurements from the Van Allen Probes, we identify clear correlations between the hydrogen- and helium-band EMIC waves with the enhancement of trapped helium and oxygen ion fluxes, respectively. We calculate the diffusion coefficients of different ion species using quasi-linear theory to understand the effects of resonant scattering by EMIC waves. Our calculations indicate that EMIC waves can cause pitch angle scattering loss of several keV to hundreds of keV ions, and heating of tens of eV to several keV helium and oxygen ions by hydrogen- and helium-band EMIC waves, respectively. Moreover, we found that magnetosonic waves can cause the resonant heating of thermal protons. Our study indicates the importance of energy transfer from the EMIC and magnetosonic waves to ions with different species at thermal energies.
Year of Publication
2019
Journal
Geophysical Research Letters
Volume
46
Number of Pages
6258-6267
Date Published
06/2019
URL
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2019GL083513
DOI
10.1029/2019GL083513