Energy and momentum theorems in magnetospheric processes
Energy and momentum theorems in magnetospheric processes
复制标题
磁层过程中的能量和动量定理
DOI：
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发表时间：
1973
期刊：
影响因子：
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通讯作者：
G. Siscoe
中科院分区：
文献类型：
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作者：
R. Carovillano;G. Siscoe
这篇评论涉及的几个能量和动量定理，涉及到磁层的过程，已经制定。本文主要考虑的区域是电离层与行星际介质之间的磁层域，不过，为了研究某些现象，电离层和太阳风特性至关重要，必须包括在内。给出了能量定理和动量定理及其应用。由于能量是系统变量的积分性质，因此可以在不了解详细动力学过程的情况下找到分析结果。因此，粒子和磁系统能量之间的关系，并应用于磁层顶的形状和磁暴的各个阶段。特别注意对称和不对称环电流，包括能量和动量平衡条件;审查非线性自洽模型和讨论如何电荷交换和能量扩散参与恢复阶段。给出了磁暴时间扰动场的环电流和边界电流能量的综合表达式，并讨论了磁层压缩过程中发生的变化。动量定理的中心是在地磁静区期间静力平衡的要求。能量定理给出了地球上平均扰动场的表达式，而动量定理给出了穿过地球的扰动场的梯度。地球和边界电流，环电流，和尾电流之间的力量推导出各种模型。值得注意的是，现有的真空模型的地磁尾是不够的，在满足的综合要求的能量和动力学的安静时间尾巴。引入等离子体片消除了困难，因为它允许在调整地球和尾部之间的力时有额外的自由度。的等离子体片的作用，使力的调整被证明是一致的，与所观察到的薄的等离子体片亚暴之前。
This review deals with the several energy and momentum theorems that relate to magnetospheric processes that have been developed. The region of primary consideration in this paper is the magnetospheric domain that extends between the ionosphere and the interplanetary medium, although, for studying certain phenomena, ionospheric and solar wind properties are of central importance and must be included. Both energy theorems and momentum theorems with their applications are presented. Since energy is an integral property of the system variables, analytical results can be found without knowledge of detailed dynamical processes. Thus, relations are derived between particle and magnetic system energies, and application is made to the shape of the magnetopause and various phases of a magnetic storm. Particular attention is given to symmetric and asymmetric ring currents, including energy and momentum equilibrium conditions; a review of nonlinear self-consistent models and a discussion of how charge exchange and energy diffusion participate in the recovery phase are presented. Comprehensive expressions for the storm time disturbance field are given in terms of both ring current and boundary current energies, and changes that occur during magnetospheric compressions are discussed. The momentum theorems center around the requirement of static force balance during geomagnetically quiet intervals. Whereas the energy theorems give expressions for the average disturbance field over the earth, the momentum theorems give the gradient in the disturbance field across the earth. The forces between earth and the boundary current, the ring current, and the tail current are derived for various models. It is noted that existing vacuum models of the geomagnetic tail are deficient in meeting the combined requirements of energetics and dynamics of the quiet time tail. Introducing the plasma sheet removes the difficulty by allowing an extra degree of freedom in adjusting the force between the earth and the tail. The role of the plasma sheet in making force adjustments is shown to be consistent with the observed thinning of the plasma sheet before sub storms.