Van Allen Probes Bibliography is from August 2012 through September 2021 Notice:
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Direct Observation of Subrelativistic Electron Precipitation Potentially Driven by EMIC Waves
Author | Capannolo, L.; Li, W.; Ma, Q.; Chen, L.; Shen, X.-C.; Spence, H.; Sample, J.; Johnson, A.; Shumko, M.; Klumpar, D.; Redmon, R.; |
Keywords | electron precipitation; EMIC waves; FIREBIRD-II; quasi linear theory; Radiation belts; Van Allen Probes; wave particle interactions |
Abstract | Electromagnetic ion cyclotron (EMIC) waves are known to typically cause electron losses into Earth\textquoterights upper atmosphere at >~1 MeV, while the minimum energy of electrons subject to efficient EMIC-driven precipitation loss is unresolved. This letter reports electron precipitation from subrelativistic energies of ~250 keV up to ~1 MeV observed by the Focused Investigations of Relativistic Electron Burst Intensity, Range and Dynamics (FIREBIRD-II) CubeSats, while two Polar Operational Environmental Satellites (POES) observed proton precipitation nearby. Van Allen Probe A detected EMIC waves (~0.7\textendash2.0 nT) over the similar L shell extent of electron precipitation observed by FIREBIRD-II, albeit with a ~1.6 magnetic local time (MLT) difference. Although plasmaspheric hiss and magnetosonic waves were also observed, quasi-linear calculations indicate that EMIC waves were the most efficient in driving the electron precipitation. Quasi-linear theory predicts efficient precipitation at >0.8\textendash1 MeV (due to H-band EMIC waves), suggesting that other mechanisms are required to explain the observed subrelativistic electron precipitation. |
Year of Publication | 2019 |
Journal | Geophysical Research Letters |
Volume | |
Number of Pages | |
Section | |
Date Published | 11/2019 |
ISBN | |
URL | https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2019GL084202 |
DOI | 10.1029/2019GL084202 |