行星际激波引发的电离层总电子含量波动的观测研究  

Observational study of ionosphere TEC fluctuations triggered by interplanetary shock

作　　者：李想 陈兴燃 宗秋刚[1] 李泉翰 张东和[1] LI Xiang;CHEN XingRan;ZONG QiuGang;LI QuanHan;ZHANG DongHe(School of Earth and Space Sciences,Peking University,Beijing 100871,China)

机构地区：[1]北京大学地球与空间科学学院,北京100871

出　　处：《中国科学：技术科学》2021年第8期948-958,共11页Scientia Sinica(Technologica)

基　　金：民用航天技术预先研究项目(编号:D020301);国家自然科学基金项目(批准号:42011530080)资助。

摘　　要：行星际激波能使近地空间发生剧烈扰动.本文使用高时间分辨率(1 s)的地面GPS接收机数据,分析了2015年3月17日行星际激波事件中电离层总电子含量(TEC)的扰动.研究发现,激波到达地球后, TEC扰动呈现出超低频波动的特征,且不同纬度区域的波动特征不同:极区台站观测到的TEC波动幅度为~0.4 TECU,持续时间10 min以上,波动周期2~3 min,随穿刺点纬度的升高而增大;中低纬地区台站观测到的TEC波动幅度为~0.2 TECU,持续时间5~10 min,波动周期均为2 min左右.我们认为等离子体层的存在可能是导致这种TEC波动差异的原因,同时我们认为极区的TEC波动可能与磁力线共振有关,中低纬地区的TEC波动可能与空腔模振荡有关.本工作利用GPS TEC技术探测到了由行星际激波引发的电离层TEC波动,这将有助于进一步理解超低频波动在地球磁层-电离层系统中的性质,同时也进一步显示出GPS TEC技术在近地空间环境研究中的重要作用.Interplanetary shocks can cause violent disturbances in near-earth space. In this paper, we use high time-resolution(1 s) data from ground-based global position system(GPS) receivers to analyze the perturbations of ionosphere total electron content(TEC) when an interplanetary shock impacted the Earth’s magnetosphere on March 17, 2015. We found that after the shock arrived at the Earth, TEC perturbations demonstrated the characteristics of ULF waves, and the fluctuation characteristics were different in different latitude regions. The amplitude of TEC fluctuations observed by the receivers in the polar region was approximately 0.4 TECU, which lasted for more than 10 min, and the fluctuation period was 2 to 3 min, which increased with the increasing latitude of the pierce point. The amplitude of the TEC fluctuations observed by the receivers in middle and low latitude areas was approximately 0.2 TECU, which lasted for 5 to 10 min, and the fluctuation period was approximately 2 min. We suggest that the existence of plasmasphere may be the reason for such difference in TEC fluctuations, and that the TEC fluctuations in polar regions may be related to field line resonances.The TEC fluctuations in the middle and low latitude areas may be related to cavity mode oscillations. We used GPS TEC technology to detect ionosphere TEC fluctuations triggered by interplanetary shock, which can help us further understand the nature of ULF waves in the Earth’s magnetospheric-ionospheric system and can further demonstrate the important role of GPS TEC technology in the study of the near-earth space environment.

关 键 词：总电子含量(TEC) 行星际激波 超低频波 磁力线共振 空腔模振荡 

分 类 号：P352.7[天文地球—空间物理学]