Gao Z., Z. Su, H. Zhu, F. Xiao, H. Zheng, Y. Wang, C. Shen, S. Wang, (2016), Intense low-frequency chorus waves observed by Van Allen Probes: Fine structures and potential effect on radiation belt electrons, Geophysical Research Letters, 43, 967-977, doi:10.1002/2016GL067687

Abstract

Abstract Frequency distribution is a vital factor in determining the contribution of whistler mode chorus to radiation belt electron dynamics. Chorus is usually considered to occur in the frequency range 0.1–0.8fce_eq (with the equatorial electron gyrofrequency fce_eq). We here report an event of intense low-frequency chorus with nearly half of wave power distributed below 0.1fce_eq observed by Van Allen Probe A on 27 August 2014. This emission propagated quasi-parallel to the magnetic field and exhibited hiss-like signatures most of the time. The low-frequency chorus can produce the rapid loss of low-energy (∼0.1 MeV) electrons, different from the normal chorus. For high-energy (≥0.5 MeV) electrons, the low-frequency chorus can yield comparable momentum diffusion to that of the normal chorus but much stronger (up to 2 orders of magnitude) pitch angle diffusion near the loss cone.

Authors (sorted by name)

Gao Zhu

Journal / Conference

Geophysical Research Letters

Acknowledgments

The EMFISIS data are available at the website (http://emfisis.physics.uiowa.edu/Flight/), and the permission to use the data does not imply endorsement of the publication of this work. This work was supported by the National Natural Science Foundation of China grants 41422405, 41274169, 41274174, 41174125, 41131065, 41421063, 41231066, and 41304134; the Chinese Academy of Sciences grant KZCX2‐EW‐QN510 and KZZD‐EW‐01‐4; the National Key Basic Research Special Foundation of China grant 2011CB811403; the Strategic Priority Research Program on Space Science of the Chinese Academy of Sciences grant XDA04060201; and the Fundamental Research Funds for the Central Universities WK2080000077.

Bibtex

@article{doi:10.1002/2016GL067687,
author = {Gao, Zhonglei and Su, Zhenpeng and Zhu, Hui and Xiao, Fuliang and Zheng, Huinan and Wang, Yuming and Shen, Chao and Wang, Shui},
title = {Intense low-frequency chorus waves observed by Van Allen Probes: Fine structures and potential effect on radiation belt electrons},
year = {2016},
journal = {Geophysical Research Letters},
volume = {43},
number = {3},
pages = {967-977},
keywords = {low-frequency chorus, rising tones, hiss-like band, cyclotron resonance, radiation belt, Van Allen Probes},
doi = {10.1002/2016GL067687},
url = {https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1002/2016GL067687},
eprint = {https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1002/2016GL067687},
abstract = {Abstract Frequency distribution is a vital factor in determining the contribution of whistler mode chorus to radiation belt electron dynamics. Chorus is usually considered to occur in the frequency range 0.1–0.8fce_eq (with the equatorial electron gyrofrequency fce_eq). We here report an event of intense low-frequency chorus with nearly half of wave power distributed below 0.1fce_eq observed by Van Allen Probe A on 27 August 2014. This emission propagated quasi-parallel to the magnetic field and exhibited hiss-like signatures most of the time. The low-frequency chorus can produce the rapid loss of low-energy (∼0.1 MeV) electrons, different from the normal chorus. For high-energy (≥0.5 MeV) electrons, the low-frequency chorus can yield comparable momentum diffusion to that of the normal chorus but much stronger (up to 2 orders of magnitude) pitch angle diffusion near the loss cone.}
}