The ionosphere-magnetosphere structure during a geomagnetic storm based on measurements in the morning auroral zone
The ionosphere-magnetosphere structure during a geomagnetic storm based on measurements in the morning auroral zone
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基于早晨极光区测量的地磁暴期间的电离层-磁层结构
DOI：
10.1029/ja091ia01p00165
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发表时间：
1986
影响因子：
--
通讯作者：
F. Rich
中科院分区：
文献类型：
--
作者：
W. Denig;F. Rich
1976年6月24日至25日，在地磁风暴发生前和发生期间，S3-2卫星对南北纬电离层的场向电流（FAC’s）、对流电场和沉降电子进行了测量。电场和FAC的模式与双胞对流的标准配置和区域1/区域2 FAC的模式不匹配。特别是，在风暴主阶段开始附近，在南半球1区电流的两极方向观测到一个强烈的（242 mV/m）对流电场和一个额外的FAC。在至少3小时的时间内进行的观测与准稳态三单元对流模式相一致，该模式具有来自行星际磁场（IMF）强By分量的应力。对强对流电场区域内的粒子和场数据的分析与Lyons（1980）的单粒子运动模型截然不同，并表明测量的FAC中有很大一部分来自电离层离子。最后，宽带静电噪声（BEN）产生的大振幅交流电波在高海拔南关（或冬季）出现，而在低海拔北关不出现。一般来说，S3-2在高海拔（1000-1500公里）冬季极光区偶尔观测到BEN，但在其他季节或低海拔地区从未检测到BEN。这些测量结果表明，场向势区域的低空极限是由局部等离子体密度决定的。
Measurements of field-aligned currents (FAC's), convection electric fields, and precipitating electrons were made by the S3-2 satellite in the midmorning time sectors of both the northern and southern high-latitude ionospheres before and during a geomagnetic storm on June 24–25, 1976. The patterns of electric fields and FAC's did not match the standard configuration of two-cell convection and the region 1/region 2 FAC's. In particular, near the beginning of the main phase of the storm an intense (242 mV/m) convection electric field and an extra FAC were observed just poleward of the region 1 current in the southern hemisphere. The observations, made over a period of at least 3 hours, were consistent with a quasi steady state three-cell convection pattern with stresses from a strong By component of the interplanetary magnetic field (IMF). An analysis of the particle and field data from within the region of the intense convection electric field is in sharp disagreement with the single-particle motion model of Lyons (1980) and implies that a significant portion of the measured FAC was from ionospheric ions. Finally, large-amplitude AC electric waves from broadband electrostatic noise (BEN) were present in the high-altitude southern (or winter) passes but not in the northern passes at lower altitudes. In general, BEN has been observed occasionally by S3-2 within the high-altitude (1000–1500 km) winter auroral regions but has never been detected during other seasons or at lower altitudes. The implication of these measurements is that the low-altitude limit for the region of field-aligned potentials is determined by the local plasma density.