Pulsating auroras produced by interactions of electrons and time domain structures
Pulsating auroras produced by interactions of electrons and time domain structures
复制标题
电子和时域结构相互作用产生的脉动极光
DOI：
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
I. Vasko
中科院分区：
文献类型：
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作者：
F. Mozer;O. Agapitov;A. Hull;S. Lejosne;I. Vasko
先前的证据表明，低波段合唱波或动力阿尔芬波散射赤道千伏电子，这些电子传播到较低的高度，在那里它们沉淀或经历进一步的低空散射，从而产生脉动极光。最近，时域结构（TDS）被证明，理论和实验，有效地散射赤道电子。为了评估这三种机制的相对重要性生产的脉动极光，11个间隔的赤道THEMIS数据和4小时间隔的货车艾伦探针测量进行了分析。在这些事件中，低波段合唱波产生的赤道电子分布的修改可以忽略不计。在几次TDS事件中，赤道0.1-3 keV的电子变得与磁场对齐。动力学阿尔芬波也可能有一个小的电子散射效应。这些研究的结论是，时域结构造成了最重要的赤道散射的~1 keV的电子对损失锥提供主要的电子贡献脉动极光。合唱波散射可能在这种极光中提供了部分最高能量（>10 keV）的电子。
Previous evidence has suggested that either lower band chorus waves or kinetic Alfven waves scatter equatorial kilovolt electrons that propagate to lower altitudes where they precipitate or undergo further low‐altitude scattering to make pulsating auroras. Recently, time domain structures (TDSs) were shown, both theoretically and experimentally, to efficiently scatter equatorial electrons. To assess the relative importance of these three mechanisms for production of pulsating auroras, 11 intervals of equatorial THEMIS data and a 4 h interval of Van Allen Probe measurements have been analyzed. During these events, lower band chorus waves produced only negligible modifications of the equatorial electron distributions. During the several TDS events, the equatorial 0.1–3 keV electrons became magnetic field‐aligned. Kinetic Alfven waves may also have had a small electron scattering effect. The conclusion of these studies is that time domain structures caused the most important equatorial scattering of ~1 keV electrons toward the loss cone to provide the main electron contribution to pulsating auroras. Chorus wave scattering may have provided part of the highest energy (>10 keV) electrons in such auroras.