A Method to Retrieve Magnetic Reconnection Locations on the Magnetopause Based on Energy-dispersion Characteristic
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摘要: 磁层顶磁场重联是太阳风向磁层输入能量的主要方式.重联如何触发一直是空间物理研究的难点,其机制仍然有待深入研究.由于卫星穿越磁层顶时,很难恰好穿越重联发生的区域,因此难以观测到重联的触发条件.本文利用THEMIS卫星观测,确立了反演磁层顶重联点的方法.当重联刚开始发生时,卫星能够观测到离子的能量色散特征,可利用其计算卫星到重联发生位置的距离.沿着磁力线模型追踪该距离即可反演出磁层顶发生重联的位置.与其他方法进行了对比分析,结果显示本文方法比其他方法具有更高的精度.Abstract: Magnetic reconnection on the magnetopause is a main way of energy transport from solar wind to magnetosphere.How magnetic reconnection is initiated is a hot yet unsolved topic in space physics research.However,on the magnetopause,it is difficult for a satellite to cross a site where reconnection is going on,and thus it is difficult to reveal the conditions which trigger magnetic reconnection.In this paper,a method is established to retrieve the locations of reconnection sites by using observations from THEMIS satellite.When reconnection initiates,the energy dispersion properties of ions ejected from the reconnection site can be observed by the satellite from a distance and are used to calculate the distance.The location of reconnection is then retrieved by tracing along modeled field lines for that distance.Our method is compared with other methods,and analyses indicate that our method may have higher accuracy than the others.
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Key words:
- Magnetopause reconnection /
- Energy dispersion /
- Tracing along field lines
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