An event on simultaneous amplification of exohiss and chorus waves associated with electron density enhancements
- Whistler mode exohiss are the structureless hiss waves observed outside the plasma pause with featured equatorward Poynting flux. An event of the amplification of exohiss as well as chorus waves was recorded by Van Allen Probes during the recovery phase of a weak geomagnetic storm. Amplitudes of both types of the waves showed a significant increase at the regions of electron density enhancements. It is found that the electrons resonant with exohiss and chorus showed moderate pitch angle anisotropies. The ratio of the number of electrons resonating with exohiss to total electron number presented in-phase correlation with density variations, which suggests that exohiss can be amplified due to electron density enhancement in terms of cyclotron instability. The calculation of linear growth rates further supports above conclusion. We suggest that exohiss waves have potential to become more significant due to the background plasma fluctuation.
Author details: | Hui ZhuORCiD, Yuri ShpritsORCiDGND, Lunjin ChenORCiD, Xu LiuORCiD, Adam C. KellermanORCiD |
---|---|
DOI: | https://doi.org/10.1029/2017JA025023 |
ISSN: | 2169-9380 |
ISSN: | 2169-9402 |
Title of parent work (English): | Journal of geophysical research : Space physics |
Publisher: | American Geophysical Union |
Place of publishing: | Washington |
Publication type: | Article |
Language: | English |
Date of first publication: | 2018/10/17 |
Publication year: | 2018 |
Release date: | 2021/07/08 |
Volume: | 123 |
Issue: | 11 |
Number of pages: | 11 |
First page: | 8958 |
Last Page: | 8968 |
Funding institution: | NSFNational Science Foundation (NSF) [AGS-1203747, AGS-1405041]; NASANational Aeronautics & Space Administration (NASA) [NNX13AE34G, NNX10AK99, NNX15AF55G]; Progress H2020 Grant [637302] |
Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Geowissenschaften |
DDC classification: | 5 Naturwissenschaften und Mathematik / 55 Geowissenschaften, Geologie / 550 Geowissenschaften |
Peer review: | Referiert |
Publishing method: | Open Access / Bronze Open-Access |