Erratum: ``Auroral polar cap boundary ion conic outflow observed on FAST''
Erratum: ``Auroral polar cap boundary ion conic outflow observed on FAST''
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DOI：
10.1029/2000ja900115
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发表时间：
2001-03
影响因子：
--
通讯作者：
Y. Tung
中科院分区：
文献类型：
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作者：
Y. Tung
我们在接近午夜的许多快速极光通道上观察到从极光极冠边界流出的大离子通量(>；108厘米−2s−1，映射到100公里)。外流是以离子锥的形式存在的，主要由能量为数百eV的轻离子组成。对1997年1月至2月期间606个快轨道进行了统计研究，以确定与亚暴有关的MLT分布和离子流出特性。我们发现，离子圆锥事件最频繁地发生在午夜附近，因此它们与夜侧中心等离子体片的直接磁连接使该离子流出成为夜侧等离子体片的电离层源。为了研究离子圆锥流出事件与极光亚暴条件之间的关系，我们使用了极光紫外成像仪(UVI)获取的全球极光图像。我们发现，流出事件与亚暴扩展阶段有很好的相关性，但离子圆锥流出事件也发生在一般活动极光期间，此时不能清楚地识别开始和扩展阶段。通过结合FAST数据来确定离子流出通量，结合ILAT范围和极地UVI图像来确定MLT范围，我们估计这些离子圆锥事件的总流出量为1,022到1,024个离子/S。通过与前人的离子流出研究相比较，我们得出结论：这些极冠边界离子圆锥事件不是整个极光椭圆形上离子流出的主要或唯一的电离层来源，而是主要的夜侧极光离子流出。
We observe large ion outflow fluxes (> 108 cm−2s−1 mapped to 100 km) flowing from the auroral polar cap boundary on many FAST auroral passes near midnight. The outflow is in the form of ion conies composed mostly of light ions with energies of hundreds of eV. A statistical study of 606 FAST orbits during January and February 1997 was done to determine the MLT distribution and ion outflow properties relative to substorms. We find that the ion conic events occur most frequently near midnight, and therefore their direct magnetic connection to the nightside central plasma sheet makes this ion outflow a candidate for the ionospheric source of the nightside plasma sheet. To study the relationship between the ion conic outflow events and auroral substorm conditions, we use global auroral images acquired from the ultraviolet imager (UVI) on Polar. We find that the outflow events are well correlated with substorm expansion phase, but ion conic outflow events also occur during generally active aurora, when onset and expansion phases were not clearly identifiable. By combining FAST data to determine ion outflow fluxes and ILAT extent and Polar UVI images to determine MLT extent, we estimate the total outflow due to these ion conic events to be 1022 to 1024 ions/s. By comparing with earlier ion outflow studies, we conclude that these polar cap boundary ion conic events are not the dominant or only ionospheric source of ion outflow over the entire auroral oval but are the dominant nightside auroral ion outflow.