Observations and model comparisons of early-time expansion characteristics of a satellite-Borne barium-lithium release at F-region altitudes
Observations and model comparisons of early-time expansion characteristics of a satellite-Borne barium-lithium release at F-region altitudes
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F区高度星载钡锂释放早期膨胀特性观测与模型比较
DOI：
10.1029/93gl01451
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
R. Schunk
中科院分区：
文献类型：
--
作者：
E. Szuszczewicz;D. Hunton;J. Wygant;R. Schunk
我们描述了CRRES G-9 Ba+/Li+云释放的极早时间膨胀过程（≈0 - 3 s），表现为热电离和光电离机制，与背景电离层的耦合以及多离子成分的微分加速度。在我们的数据分析中，我们提出了在膨胀的等离子云中静电扫雪机效应的第一个“原位”证据，并认为这些效应是双极场的结果，而离子中性碰撞的动力学效应在G-9情景中几乎没有影响。除静电扫雪机过程外，结果还显示了云中离子和中性成分膨胀的质量依赖效应。这些效应体现在观察中，Li+离子在膨胀过程中“超过”较重的Ba+，并在云的前缘呈现出先行者的特征。
We describe the very-early-time expansion processes (≈0 - 3 s) of the CRRES G-9 Ba+/Li+ cloud release, as manifested by thermal- and photo-ionization mechanisms, by coupling to the background ionosphere, and by differential acceleration of multi-ion constituents. In our data analysis we present the very first “in situ” evidence of electrostatic snowplow effects in an expanding plasma cloud, with arguments that these effects are the result of ambipolar fields and that kinetic effects of ion-neutral collisions have little influence in the G-9 scenario. In addition to the electrostatic snowplow process, the results show mass-dependent effects on the expansion of ion and neutral constituents in the cloud. These effects are manifested in the observation that the Li+ ions “outpace” the heavier Ba+ in the expansion process, and take on forerunner characteristics at the cloud's leading edge.