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  • Mid‐Latitude Auroras and Energetic Particle Precipitation Occurred Unusually in a Moderate Magnetic Storm on 1 December 2023
Title: Mid‐Latitude Auroras and Energetic Particle Precipitation Occurred Unusually in a Moderate Magnetic Storm on 1 December 2023
Abstract Mid‐latitude auroras are conventionally generated during intense magnetic storms. However, mid‐latitude auroras were observed by naked eyes at Beijing China (39°N, 116°E) unusually during a moderate storm event on 1 December 2023 with the minimum Sym‐H index only −120 nT. This study combines conjugative in‐site and ground‐based observations to analyze the auroras and underlying physical processes. Results indicate that both electron and proton auroras appeared at low latitudes. Electron auroras predominantly arise from low‐energy electron precipitation, but proton auroras may be explained by energetic tens of keV proton precipitation. Pc1/EMIC waves are observed at low latitudes in the ionosphere, potentially accounting for mid‐latitude proton auroras. Downward field‐aligned currents (FACs) are also detected at low latitudes, producing significant magnetic perturbations. This study reveals the underlying ionospheric responses to the mid‐latitude auroras to understand potential reasons for observing aurora at such mid‐latitudes during a moderate storm.  more » « less
Award ID(s):
2002574
PAR ID:
10610505
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Geophysical Research Letters
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
51
Issue:
18
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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