Monoenergetic high-energy electron precipitation in thin auroral filaments
Monoenergetic high-energy electron precipitation in thin auroral filaments
复制标题
细极光丝中的单能高能电子沉淀
DOI：
10.1029/2012gl053466
复制
发表时间：
2012
影响因子：
5.2
通讯作者：
Dahlgren H
中科院分区：
文献类型：
--
作者：
Dahlgren H
产生极窄（70 m）动态极光细丝的电子析出的能量分布在8kev左右达到尖峰。这些事件是由位于挪威特罗姆瑟附近的高分辨率低光光学成像仪拍摄的。该方法在两个对极光电子沉淀具有不同能量依赖响应的发射中使用成像。这些事件的关键特征是没有检测到两次发射的高度差异，也没有任何飞行时间弥散，因此得出结论，细丝是由单能降水引起的。与电子传递和离子化学模型的比较表明，高能量细丝嵌入在约4 keV的低能量沉淀区。目前还没有一致的理论来解释观测到的极光结构的特征。
The energy distribution of the electron precipitation responsible for extremely narrow (70 m) and dynamic auroral filaments is found to be sharply peaked at around 8 keV. The events were captured with high resolution low‐light optical imagers located near Tromsø, Norway. The method uses imaging in two emissions which have different energy dependent responses to auroral electron precipitation. The key feature of the events was that no difference in the altitude of the two emissions was detected, nor any time‐of‐flight dispersion, thus leading to the conclusion that the filaments were caused by monoenergetic precipitation. Comparisons with an electron transport and ion chemistry model show that the high energy filaments were embedded in a region of lower energy precipitation of about 4 keV. There is currently no consistent theory to explain the characteristics of the observed auroral structures.