由时域结构和 ECH 波驱动的类脉冲红线形极光
摘要
Auroral streamers are important meso-scale processes of dynamic magnetosphere-ionosphere coupling，typically studied using imagers sensitive to energetic (>1 keV) electron precipitation，such as all-sky imagers (ASIs)。This paper reports streamer-like red-line auroras，representing low-energy (<1 keV) precipitation，observed poleward of a black aurora and an auroral torch。These red-line auroras were associated with a magnetospheric electron injection and braking ion flows。Observations were made using the THEMIS spacecraft and ground-based imagers，including the ASI，REGO，and meridian scanning photometer (MSP) at Fort Smith。We identify plasma sheet electron pitch-angle scattering by time-domain structures (TDSs) and electron cyclotron harmonics (ECH) waves as the driver of these red-line auroras，because of (1) a strong correlation (~0.9) between observed red-line intensities and precipitating fluxes；(2) consistent red-line intensities from auroral transport code forward modeling；and (3) consistent precipitation characteristic energies from MSP optical inference and quasi-linear estimates。
引用
@article{arxiv.2502.18692,
title = {Streamer-like red line diffuse auroras driven by time domain structures and ECH waves associated with a plasma injection and braking ion flows},
author = {Yangyang Shen and Xu Zhang and Jun Liang and Anton Artemyev and Vassilis Angelopoulos and Emma Spanswick and Larry Lyons and Yukitoshi Nishimura},
journal= {arXiv preprint arXiv:2502.18692},
year = {2025}
}
备注
18 pages, 3 figures, to be submitted to Geophysical Research Letters