Polar cap size and potential: A predicted relationship
Polar cap size and potential: A predicted relationship
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极冠大小和潜力：预测关系
DOI：
10.1029/gl009i006p00672
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发表时间：
1982
影响因子：
5.2
通讯作者：
G. Siscoe
中科院分区：
文献类型：
--
作者：
G. Siscoe
Vasyliunas、Wolf 和 Southwood 在不同论文中发展成一般形式主义的磁层对流与电离层之间自洽相互作用模型导致了第 2 区伯克兰电流系统在电离层中形成的环的半径 b（被视为因变量）与交叉极帽电势 Φ 和极帽半径 a（被视为自变量）之间的基本关系。当在时间相关模型中考虑 Φ 对 a 的控制时，我们发现 a 的增长速度比 b 快得多。这导致了一个两难的困境，可以利用亚暴通过去除极冠上的磁通量来解决这个问题。亚暴之前等离子体层变薄是该模型的简单几何结果。对于稳定电势，系统演化到稳定状态，极帽和区域 2 环的尺寸对 Φ 的函数依赖性为 (a/Re) = α Φ3/16, (b/Re) = β Φ3/16，其中 α 和 β 常数满足 β - α « (1/2) (β+α)。也就是说，正如观察到的那样，预计环间间距远小于环的半径。
The model of the self-consistent interaction between magnetospheric convection and the ionosphere as developed into a general formalism in separate papers by Vasyliunas, Wolf and Southwood leads to a fundamental relationship between the radius b of the ring formed in the ionosphere by the Region 2 Birkeland current system, regarded as a dependent variable, and the cross polar cap potential Φ and polar cap radius a, regarded as independent variables. When the control of Φ on a is taken into consideration in a time dependent model, one finds that a grows much more rapidly than b. This leads to a dilemma, which substorms can be used to resolve by removing magnetic flux from the polar cap. Thinning of the plasma sheet prior to substorms emerges as a simple, geometrical consequence of the model. For a steady potential, the system evolves to a steady state for which the functional dependences of the sizes of the polar cap and the Region 2 ring on Φ are found to be (a/Re) = α Φ3/16, (b/Re) = β Φ3/16, with α and β constants which satisfy β - α « (1/2) (β+α). That is, the inter-ring separation is predicted to be much less than the radii of the rings, as is observed.