EGU26-21007, updated on 14 Mar 2026
https://doi.org/10.5194/egusphere-egu26-21007
EGU General Assembly 2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
Poster | Wednesday, 06 May, 10:45–12:30 (CEST), Display time Wednesday, 06 May, 08:30–12:30
 
Hall X4, X4.152
MLT dependence of diffuse auroral electron precipitation energy
Gaël Cessateur1, Keisuke Hosokawa2,3, Hervé Lamy1, Sota Nanjo4, Mathieu Barthelemy5, Magnar G. Johnsen6, and Romain Maggiolo1
Gaël Cessateur et al.
  • 1Royal Belgian Institute for Space Aeronomy, Avenue Circulaire 3, 1180 Brussels, Belgium
  • 2Department of Communication Engineering and Informatics, University of Electro-Communications, Tokyo, Japan
  • 3Center for Space Science and Radio Engineering, University of Electro-Communications, Tokyo, Japan
  • 4Swedish Institute of Space Physics, IRF Kiruna, 981 92 Kiruna, Sweden
  • 5Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France
  • 6Tromsø Geophysical Observatory, Faculty of Science and Technology, UiT the Arctic University of Norway, N-9037 Tromsø, Norway

More than 20,000 visible spectra of diffuse auroras were recorded by the Auroral Spectrograph In Skibotn (ASIS), operating since October 2023 within the auroral oval. An AI-based classification was used to identify diffuse auroral intervals. The characteristic energy of precipitating electrons was then estimated from the ratio of calibrated red (630.0 nm) and blue (427.8 nm) emissions, using lookup tables derived from a kinetic electron transport model. Within a Bayesian regression framework, the dependence of the inferred electron energy on magnetic local time was investigated. The results reveal a clear post-midnight hardening of the precipitating electron population toward the dawn sector, with a transition occurring near 04 MLT, consistent with previous optical, radar, and satellite studies.

How to cite: Cessateur, G., Hosokawa, K., Lamy, H., Nanjo, S., Barthelemy, M., Johnsen, M. G., and Maggiolo, R.: MLT dependence of diffuse auroral electron precipitation energy, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-21007, https://doi.org/10.5194/egusphere-egu26-21007, 2026.