Surface conductivity of Mercury provides current closure and may affect magnetospheric symmetry
Surface conductivity of Mercury provides current closure and may affect magnetospheric symmetry
复制标题
水星的表面电导率提供电流闭合并可能影响磁层对称性
DOI：
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
E. Kallio
中科院分区：
文献类型：
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作者：
P. Janhunen;E. Kallio
抽象的。我们研究了什么样的影响，可能的表面电导率的水星磁层电流的关闭，使六个运行与准中性的混合模拟。运行在其他方面是相同的，但使用不同的合成电导率模型：运行1具有完全导电的行星，运行2具有导电不良的行星（m），运行3-6具有在黎明-黄昏或昼夜方向上的半球之一，导电良好，另一个导电不良。虽然无法从观测中得知表面的传导率，但有根据的猜测很容易得出这样的传导率值，即磁层电流可能在行星内部部分闭合，而且由于传导率在很大程度上取决于表面的矿物成分，因此不能轻易排除显著水平变化的可能性。模拟结果表明，强烈的水平变化可能会产生适度的磁层不对称性。除了混合动力模拟，我们还简要讨论了可能性，即在夜面可能缺乏表面电子携带向下的电流，这可能是一个进一步的来源，表面相关的磁层不对称性。关键词。磁层物理学（行星磁层;电流系统;太阳风-磁层相互作用）。
Abstract. We study what effect a possible surface conductivity of Mercury has on the closure of magnetospheric currents by making six runs with a quasi-neutral hybrid simulation. The runs are otherwise identical but use different synthetic conductivity models: run 1 has a fully conducting planet, run 2 has a poorly conducting planet ( m ) and runs 3-6 have one of the hemispheres either in the dawn-dusk or day-night directions, conducting well, the other one being conducting poorly. Although the surface conductivity is not known from observations, educated guesses easily give such conductivity values that magnetospheric currents may close partly within the planet, and as the conductivity depends heavily on the mineral composition of the surface, the possibility of significant horizontal variations cannot be easily excluded. The simulation results show that strong horizontal variations may produce modest magnetospheric asymmetries. Beyond the hybrid simulation, we also briefly discuss the possibility that in the nightside there may be a lack of surface electrons to carry downward current, which may act as a further source of surface-related magnetospheric asymmetry. Key words. Magnetospheric physics (planetary magnetospheres; current systems; solar wind-magnetosphere interactions).6