极隙区Pc3频段脉动的传播特性  

PROPAGATION CHARACTERISTICS OF THE Pc3 FREQUENCY RANGE PULSATION IN THE CUSP LATITUDES

作　　者：刘勇华 刘瑞源 杨少峰[2] 贺龙松 BJFraser 

机构地区：[1]中国极地研究所,上海200129 [2]中国科学院地球物理研究所,北京100101 [3]纽卡斯尔大学

出　　处：《极地研究》2000年第2期121-128,共8页Chinese Journal of Polar Research

基　　金：国家自然科学基金!( 4963 4 1 60 );国家海洋局海洋青年基金资助!( 9760 2 )

摘　　要：南极中山站和戴维斯站 (不变磁纬 74.5°S)白天中午位于磁层极隙区 ,夜间位于极盖区或极光带的极向边沿。两站均安装了完全相同的感应式磁力计。选择两站 1 997年 3月和 1 996年 6、9、1 2月的数据 ,运用快速傅立叶变换和波形检查方法选择 Pc3频段脉动事件 ,然后用信号互谱技术进行统计分析 ,结果如下 :在中山站 -戴维斯站 ,Pc3频段脉动主要出现于白天中午 /磁中午和磁午夜附近 ;白天 ,Pc3频段脉动振幅、出现率和出现的时间范围均有一定的季节变化 ,冬季最小 ,但在夜间 ,Pc3频段脉动没有这种变化 ;夜间 ,Pc3频段脉动振幅比在白天大许多 ;Pc3频段脉动传播方向 ,白天主要向西 ,夜间不太规则。这些可能反映了电离层电导率和日侧电离层电流系统对 Pc3频段脉动的影响。WT5BZ] Two induction magnetometers have been installed at Zhongshan and Davis Stations, Antarctica respectively. We adopt with cross spectral analysis technique to analyze the data of the two induction magnetometers, in June, September, December 1996 and March 1997, to investigate the Pc3 frequency range pulsation occurrence and propagation characteristics in the cusp latitudes. The results are summarized as following: At Zhongshan Davis Station, the Pc3 frequency range pulsation occurs mainly around the local noon/ local magnetic noon and local magnetic midnight respectively. In daytime, the pulsation has a seasonal variation in amplitude, occurrence and temporal range, all of them are smallest in winter. But in nighttime, the pulsation has no such a variation. The pulsation amplitude is much larger in nighttime than in daytime all over the year. The pulsation propagating direction is mainly western in daytime and irregularly in nighttime. It can be thought that the different sources of the pulsation and the ionospheric electric conductivity are mainly responsible for these characteristics.

关 键 词：Pc3频段脉冲 极隙区 传播 磁层 地磁脉动 

分 类 号：P318[天文地球—固体地球物理学]