北京地区Pc6脉动统计特征及其与TID关系研究

Through the statistical analysis of the geomagnetic data from BMT in 2005, we get the period and frequency characteristic of Pc6 micropulsation in Beijing area. Pc6 micropulsation is a frequently occurred phenomenon in geomagnetism but we still do not have adequate knowledge to it. In this paper, we found that the periods of Pc 6 micropulsation focus on 10 to 30 minutes. They do not have distinct seasonal variation but obtain a little lower occurrence in the winter than other seasons. Then we analysis the geomagnetic data of BMT from 1998 to 2006, which is a solar activity cycle and get some results about the relationship between Pc6 micropulsation and solar activities. In this way, we discuss more about the origin and evolvement mechanism of the Pc6 micropulsation. When the solar is more active than usual years, there are more occurrences of Pc6 micropulsaton observed. The occurrence of Pc6 micropulsation is associated with geomagnetic index. With the increase of AE and Kp index, there are more occurrences of Pc6 micropulsation. Furthermore, we make use of the Doppler data from Peking University in 2005 make a comparative research between TID events and Pc6 micropulsation. There are 42 events can satisfy our request during Dec.23, 2004 to Mar.11, 2006. After the data analysis, we can draw a fundamental conclusion that there are positive links between Pc6 micropulsation and TID event. Moreover, when TID and Pc6 micropulsation occur simultaneously, their occurrences have a positive relationship with AE and Kp index. So we suppose there might be the same source of Pc6 micropulsation and TID event. Finally, we make use of two meridian geomagnetic stations network which has a distance about 1700 km to investigate the transmission characteristic of Pc6 micropulsation when Pc6 micropulsation and TID happened together. We found at that time Pc6 micropulsation is a local phenomenon.