Quantitative studies of the Earth's ionospheric-origin ions on the outflow/supply to the magnetosphere and the acceleration/heating and transpotation processes

首先，基于Akebono卫星观测资料，研究了预计会引起电离层离子加速/加热的等离子体波的性质。统计调查了这些波与流出离子曲线的关系，特别是从高度、俯仰角、磁纬度和当地时间等事件的发生频率方面进行了调查。详细的波形分析表明，低频随机噪声型波和零星尖峰型波是相互叠加的两种波形。根据Akebono数据分析，光电子效应对极地风事件的重要性也变得清晰起来。一方面，近年来多颗卫星观测数据的结果验证了二次旋回事件与行星际磁场的相关性。我们还分析了Geotail数据，以估计电离层起源离子从极地电离层逃逸后在磁层中的流出通量。需要注意的是，我们考虑了从地球大气中喷射出来的电离层离子的所有路径，以便计算出正确的地源离子在磁层中的数量。利用EISCAT最近的观测资料，研究了在低空触发离子外流的电离层离子加热现象。各向异性俯仰角分布很可能对离子加热/加速起着至关重要的作用，这是在高海拔观测到的离子流出事件的原因。

First of all, we investigated the properties of plasma waves which are expected to cause the ionospheric ion acceleration/heating on the basis of the Akebono satellite observations. The relationships of these waves to the outflowing ion conics were statistically surveyed especially from aspects of their occurrence frequencies of events sorted into altitudes, pitch angles, magnetic latitude, and local time. Our detailed wave analyzes presented two types of wave forms, namely, low-frequency random noise-type wave and sporadic spike-type wave, two of which superimpose each other. The importance of photoelectron effects on polar wind events is also become clear according to the Akebono data analyzes. On one hand, the recent results of multi-satellite observation data verified the dependence of the conics events on the interplanetary magnetic field. We also analyzed the Geotail data for estimate of the outflow fluxes in the magnetosphere of the ionospheric origin ions after their escape from the polar ionosphere. It should be noted that we take all routes of the ionospheric ions after the ejection from the terrestrial atmosphere into account in order to calculate correct amount of the terrestrial-origin ions in the magnetosphere. The recent observation data from EISCAT were used for exploring the ionospheric ion heating phenomena at low altitutes where at is expected that the ion outflows are triggered. It is likely that the anisotropic pitch angle distribution plays an crucial role for ion heating/acceleration as a cause of the ion outflow events observed at high altitudes.