Multiple auroral brightenings and associated Pi 2 pulsations
Multiple auroral brightenings and associated Pi 2 pulsations
复制标题
多次极光增亮和相关的 Pi 2 脉动
DOI：
10.1029/2001gl014583
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发表时间：
2002
影响因子：
5.2
通讯作者：
J. Olson
中科院分区：
文献类型：
--
作者：
K. Shiokawa;K. Yumoto;J. Olson
本文利用阿拉斯加Kotzebue （KOT, 64.4°MLAT）的全天极光数据，以及高纬度和低纬度站点的磁场数据，证明了一次孤立亚暴期间多次极光变亮与Pi 2磁脉动之间的关系。在生长阶段结束前后的磁场数据中至少识别出五个Pi 2波包。极光亮度变化在Pi - 2频率范围内不显示振荡，尽管每个Pi - 2波包与每次小尺度极光增亮和向极地运动具有良好的对应关系。这一事实可能与高纬度Pi - 2由亚暴场定向电流振荡产生的观点相矛盾。我们从π 2电流系统的局域化和作为电流载流子的低能电子讨论了这种差异的可能原因。
All‐sky auroral data at Kotzebue (KOT, 64.4° MLAT), Alaska, and magnetic field data from both high‐ and low‐latitude stations are used to demonstrate the relation between multiple auroral brightenings and Pi 2 magnetic pulsations during an isolated substorm. At least five Pi 2 wave packets are identified in the magnetic field data around the end of the growth phase. Auroral luminosity variations do not show oscillations in the Pi 2 frequency range, though each Pi 2 wave packet has good correspondence with each small‐scale auroral brightening and poleward motion. This fact may contradict the idea of high‐latitude Pi 2 generation by oscillations of substorm field‐aligned currents. We discuss possible reasons of this discrepancy from localization of the Pi 2 current system and low‐energy electrons as the current carrier.