First direct optical observations of plasma flows using afterglow of in discrete aurora
First direct optical observations of plasma flows using afterglow of in discrete aurora
复制标题
首次利用离散极光的余辉对等离子体流进行直接光学观测
DOI：
10.1016/j.jastp.2008.11.015
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发表时间：
2009
影响因子：
1.9
通讯作者：
Dahlgren H
中科院分区：
文献类型：
--
作者：
Dahlgren H
在732.0nm的O+离子禁戒线上对活动结构极光成像，为直接观测顶侧电离层等离子体漂移提供了可能。亚稳态O+2 P的辐射寿命为5秒，因此在产生氧离子的沉淀停止后，可以检测到氧离子。的O+发射的衰减时间进行了研究和建模与时间相关的电子传输和离子化学模型。给出了2006年在挪威特罗姆瑟附近使用多光谱成像仪极光结构和动力学（ASK）观测到的O+余辉的四个例子。估计的漂移速度产生的余辉运动的分析。体等离子体的速度为340和720米/秒指向东方的两个余辉电弧丝，对应于向南的电场分别为18和40毫伏/米。
Imaging of active structured aurora in the forbidden O+ion line at 732.0nm provides a possibility of direct observation of plasma drifts in the topside ionosphere. The metastable O+2P state has a radiative lifetime of 5s, so the oxygen ions can be detected after the precipitation creating them has ceased. The decay time of the O+emission is studied and modelled with a time-dependent electron transport and ion chemistry model. Four examples are given of O+afterglow observed with the multi-spectral imager, auroral structure and kinetics (ASK), which was located near Tromsø, Norway, in 2006. Estimates are given of drift velocities resulting from the analysis of the afterglow motions. Bulk plasma velocities of 340 and 720m/s directed eastwards were found for two afterglowing arc filaments, corresponding to southward electric fields of 18 and 40mV/m, respectively.