Observational Evidence for the Nonlinear Growth of Chorus Waves Caused by Substorm Injected Energetic Electrons
Abstract Substorm energetic electron injections serve as a significant energy source for chorus wave generation, markedly altering the distribution of energetic electrons. Using the Arase satellite data, we present direct evidence for the nonlinear evolution of chorus waves following a substorm injection. The substorm injection causes the enhancement of energetic electron fluxes (∼20–200 keV) during which chorus waves appear as clear and intense rising‐tone elements. Linear theoretical analysis shows that anisotropic energetic electrons provide free energy for the generation of seed chorus waves and the enhancement of energetic electrons increases the linear growth rate. Furthermore, nonlinear theoretical analysis shows that the increase in energetic electrons reduces the threshold amplitude, which is conducive to the chorus wave entering the nonlinear growth stage. These results indicate that nonlinear growth plays a significant role in the amplification and spectral evolution of chorus waves through a decrease in the threshold amplitudes.
Authors
- Hong Zhao (ORCID: https://orcid.org/0000-0001-8292-7691)
- Takefumi Mitani (ORCID: https://orcid.org/0000-0003-0492-3104)
- Rui Chen (ORCID: https://orcid.org/0000-0002-4828-5709)
- Yoshiya Kasahara (ORCID: https://orcid.org/0000-0002-9304-8235)
- Shoya Matsuda (ORCID: https://orcid.org/0000-0003-4778-8897)
- Iku Shinohara (ORCID: https://orcid.org/0000-0003-2700-0353)
- Kazuhiro Yamamoto (ORCID: https://orcid.org/0000-0002-2515-8643)
- Fuminori Tsuchiya (ORCID: https://orcid.org/0000-0003-3386-6794)
- Ayako Matsuoka
- Huayue Chen (ORCID: https://orcid.org/0000-0002-7619-701X)
- Shoichiro Yokota (ORCID: https://orcid.org/0000-0001-8851-9146)
- M. Teramoto (ORCID: https://orcid.org/0000-0001-5983-1149)
- K. Keika (ORCID: https://orcid.org/0000-0003-0265-4318)
- Atsushi Kumamoto (ORCID: https://orcid.org/0000-0002-3988-1488)
- Xueyi Wang (ORCID: https://orcid.org/0000-0001-5533-5981)
- Tomoaki Hori (ORCID: https://orcid.org/0000-0001-8451-6941)
- Satoshi Kasahara (ORCID: https://orcid.org/0000-0002-3479-772X)
- Yoshizumi Miyoshi (ORCID: https://orcid.org/0000-0001-7998-1240)
- Takeshi Takashima (ORCID: https://orcid.org/0000-0002-7818-7800)
- Atsuki Shinbori (ORCID: https://orcid.org/0000-0003-4519-4526)
Institutions
- Kanazawa University (JP)
- Tohoku University (JP)
- Kyushu Institute of Technology (JP)
- Kyoto University (JP)
- Japan Aerospace Exploration Agency (JP)
- Kyung Hee University (KR)
- Institute of Space and Astronautical Science (JP)
- Nagoya University (JP)
- The University of Tokyo (JP)
- Auburn University (US)
- The University of Osaka (JP)
Publication Details
- Journal
- Journal of Geophysical Research Space Physics
- Published
- 2025-07-01
- DOI
- https://doi.org/10.1029/2025ja033931
- Citations
- 3
- Primary Topic
- Ionosphere and magnetosphere dynamics
- Type
- article
- Field-Weighted Citation Impact
- 3.46
Funders
- Japan Society for the Promotion of Science