EGU24-4512, updated on 08 Mar 2024
https://doi.org/10.5194/egusphere-egu24-4512
EGU General Assembly 2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.

Ionospheric responses modulated by quasi-periodic EMIC waves associated with ULF waves

Longxing Ma1,2, Yiqun Yu1,2, Xin Tong1,2, Linhui Tang1,2, Wenlong Liu1,2, Jinbin Cao1,2, Jun Wu3, and Jian Wu3
Longxing Ma et al.
  • 1School of Space and Environment, Beihang University, Beijing, China
  • 2Key Laboratory of Space Environment Monitoring and Information Processing, Ministry of Industry and Information Technology, Beijing, China
  • 3National Key Laboratory of Electromagnetic Environment, China Research Institute of Radio Wave Propagation, Beijing, China
Energetic protons can be efficiently scattered by electromagnetic ion cyclotron (EMIC) waves into the upper atmosphere. This process represents a crucial mechanism for the exchange of energy and particles between the magnetosphere and ionosphere. In this study, quasi-periodic EMIC waves induced by Pc4 ULF waves were observed by the Van Allen Probes (RBSP) B satellite during a magnetic storm event on September 8, 2017. The associated pitch angle diffusion coefficient 𝐷𝛼𝛼 reveals that the quasi-periodic EMIC waves predominantly affect 30-100 keV protons. Concurrently, RBSP-B measurements indicated a remarkable quasi-periodic enhancement in the proton flux near the loss cone, with a frequency consistent with EMIC wave packets. Observations from the NOAA-19 satellite exhibited a substantial increase in 30-100 keV proton precipitating fluxes. Periodic proton precipitation resulted in clearly quasi-periodic enhancements of electron density in the ionospheric E-region detected by the European Incoherent Scatter (EISCAT) radar.

How to cite: Ma, L., Yu, Y., Tong, X., Tang, L., Liu, W., Cao, J., Wu, J., and Wu, J.: Ionospheric responses modulated by quasi-periodic EMIC waves associated with ULF waves, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4512, https://doi.org/10.5194/egusphere-egu24-4512, 2024.