Direct evidence of the pitch angle scattering of relativistic electrons induced by EMIC waves

Author
Keywords
Abstract
In this study, we analyze an EMIC wave event of rising tone elements recorded by the Van Allen Probes. The pitch angle distributions of relativistic electrons exhibit a direct response to the two elements of EMIC waves: at the intermediate pitch angle the fluxes are lower and at the low pitch angle the fluxes are higher than those when no EMIC was observed. In particular, the observed changes in the pitch angle distributions are most likely to be caused by nonlinear wave particle interaction. The calculation of the minimum resonant energy and a test particle simulation based on the observed EMIC waves support the role of the nonlinear wave-particle interaction in the pitch angle scattering. This study provides direct evidence for the nonlinear pitch angle scattering of electrons by EMIC waves.
Year of Publication
2020
Journal
Geophysical Research Letters
Date Published
01/2020
ISSN Number
0094-8276
URL
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2019GL085637
DOI
10.1029/2019GL085637