在高导电性磁性水力动力学流中,流体结分解
Gregory Eyink1, Ethan Vishniac, Cristian Lalescu
1Department of Applied Mathematics & Statistics, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, USA. eyink@jhu.edu
Nature
|May 24, 2013
概括
动荡的理查德森向导为天体物理等离子体中的快速磁重新连接提供了新的解释,挑战了传统的理论.
科学领域:
- 血物理学的等离子体物理学
- 天体物理学 天体物理学
- 磁动力学 磁动力学
背景情况:
- "结"磁场线概念解释了天体物理现象,但未能解释像太阳耀斑这样的高导电性等离子体中的快速磁拓变化.
- 微物理等离子体过程是快速连接的解释之一,但它们在大型天体物理尺度上的有效性仍然不确定.
研究的目的:
- 为了研究流理查德森向导能否解释天体物理学等离子体中大规模磁流结构的快速重新连接.
- 分析磁动力学流的模拟,以了解流量结的分解.
主要方法:
- 在高导电率下对磁动力学 (MHD) 流的模拟分析.
- 研究理查森分散及其对磁场线运动的影响.
主要成果:
- 模拟显示了理查德森分散,其中流向使磁场线汇聚在一起.
- 这一过程导致"自发性随机"的线路运动,打破了比离子旋转半径更大的尺度上的标准流量结.
- 流体结的分解解释了大规模磁性结构的快速重新连接.
结论:
- 动荡的理查德森倾向为太阳耀斑和冠状质量喷射等天体物理现象中的快速磁再连接提供了可行的解释.
- 这种机制适用于各种天体物理环境,包括积累盘和马射线爆发.
- 在特定的等离子体流量条件下,静态流量结使快速重新连接与标准的结状态相协调.
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