Cao X., Y. Y. Shprits, B. Ni, I. S. Zhelavskaya, (2017), Scattering of Ultra-relativistic Electrons in the Van Allen Radiation Belts Accounting for Hot Plasma Effects, Scientific Reports, 7, 17719, doi:10.1038/s41598-017-17739-7

Abstract

Electron flux in the Earth’s outer radiation belt is highly variable due to a delicate balance between competing acceleration and loss processes. It has been long recognized that Electromagnetic Ion Cyclotron (EMIC) waves may play a crucial role in the loss of radiation belt electrons. Previous theoretical studies proposed that EMIC waves may account for the loss of the relativistic electron population. However, recent observations showed that while EMIC waves are responsible for the significant loss of ultra-relativistic electrons, the relativistic electron population is almost unaffected. In this study, we provide a theoretical explanation for this discrepancy between previous theoretical studies and recent observations. We demonstrate that EMIC waves mainly contribute to the loss of ultra-relativistic electrons. This study significantly improves the current understanding of the electron dynamics in the Earth’s radiation belt and also can help us understand the radiation environments of the exoplanets and outer planets.

Authors (sorted by name)

Cao Ni Shprits Zhelavskaya

Journal / Conference

Scientific Reports

Acknowledgments

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 637302 and the Helmholtz Association Recruiting Initiative. The work at Wuhan University was supported by the NSFC grants 41674163, 41474141, and 41204120 and the Hubei Province Natural Science Excellent Youth Foundation (2016CFA044). X.C. would like to acknowledge the support from Wuhan University Doctoral Students Short-term Study Abroad Project. We would like to thank Maria Usanova and Lynn Kistler for useful discussions.

Grants

637302

Bibtex

@article{doi:10.1038/s41598-017-17739-7,
author = {Cao, Xing and Shprits, Yuri Y. and Ni, Binbin and Zhelavskaya, Irina S.},
title = {Scattering of Ultra-relativistic Electrons in the Van Allen Radiation Belts Accounting for Hot Plasma Effects},
journal = {Scientific Reports },
year = {2017},
volume = {7},
number = {1},
pages = {17719},
doi = {10.1038/s41598-017-17739-7},
abstract = {Electron flux in the Earth’s outer radiation belt is highly variable due to a delicate balance between competing acceleration and loss processes. It has been long recognized that Electromagnetic Ion Cyclotron (EMIC) waves may play a crucial role in the loss of radiation belt electrons. Previous theoretical studies proposed that EMIC waves may account for the loss of the relativistic electron population. However, recent observations showed that while EMIC waves are responsible for the significant loss of ultra-relativistic electrons, the relativistic electron population is almost unaffected. In this study, we provide a theoretical explanation for this discrepancy between previous theoretical studies and recent observations. We demonstrate that EMIC waves mainly contribute to the loss of ultra-relativistic electrons. This study significantly improves the current understanding of the electron dynamics in the Earth’s radiation belt and also can help us understand the radiation environments of the exoplanets and outer planets.}
}