Analysis of Geomagnetic ULF wave phenomena with data from IMS Magnetometer Network and Geosynchronous satellites data from IMS Magnetometer Network and Geosynchronous satellites

(1)购买了1978年2月至1980年4月期间的国际监测系统磁强计网络数据和1974年至1983年SMS/GOES地球同步卫星数据。(2)计算机软件的开发，使大部分的数据分析可以在我们的实验室的超级微型计算机。(3)研究了磁层突然膨胀过程中的磁场变化。结果表明，膨胀效应是由快模膨胀波向低纬传播，由横模向高纬传播。这与磁层突然压缩（sc）的情况类似，但意义相反。(4)本文对动态探测者二号卫星在低纬（地磁纬度32 °）和低空（750 km）探测到的一次地磁脉动（Psc）进行了分析。周期约为13秒。对地面磁图的检查表明，每条力线都有自己的本征周期，从低纬的1秒到高纬的400秒不等。(5)如果太阳风动压存在振荡变化，并且周期大于磁层效应的传播时间，则该效应将通过与sc相同的机制传递到地面。考虑到这一点，对地面磁图和太阳风数据进行了检查，发现了一个符合预期的事件。周期为6-16 min的振荡在经度相隔较远的低纬站出现了波形相似的相干振荡。在高纬度地区，各站的周期和相位各不相同。(6)根据我们迄今为止所作的分析，建立了一个供应链模型。

(1) The IMS Magnetometer Network data for the period, February, 1978 - April, 1980 and SMS/GOES geosynchronous Satellites Data for 1974 - 1983 were purchased.(2) The computer software was developed so that the most of the data analysis could be made by the super-mini-computer in our laboratory.(3) Magnetic variations during sudden expansions of the magnetoshere were studied. It was found that the effect of the expansion was transmitted by the fast mode expansion wave to low latitudes and by the transverse mode to high latitudes. This is similar but opposite in sense to the case of the sudden compression of the magnetosphere, (sc).(4) An analysis was made for a Psc (geomagnetic pulsation associated with sc) detected by the Dynamic Explorer-2 satellite at low latitude (geomagnetic latitude: 32^o) and at low altitude (750km). The period ws about 13 sec. The inspection of ground magnetograms showed each line of force was resonated with its own eigen period ranging 1 sec in low latitudes to 400 sec in high latitudes.(5) If there is an oscillatory variation in the solar wind dynamic pressure and if the period is longer than propagation time of the effect in the magnetosphere, the effect will be transmitted to the ground by the same mechanism as sc. Keeping this idea in mind, gound magnetograms and solar wind data were checked and an event was found which fulfils expectation. The oscillation (the period: 6-16 min) appeared coherently with similar waveform at low latitude stations widely separated in longitude. The period and phase varied from station to station in high latitudes.(6) A model for sc was developed based upon our analyses made so far.