arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1502.01311astro-ph.SR
收藏

重联对太阳开-闭通量边界结构的影响

The effect of reconnection on the structure of the Sun's open-closed-flux boundary

D. I. Pontin, P. F. Wyper

摘要:

全球磁场推断现在揭示了太阳日冕的巨大复杂性,特别是开放和封闭磁通量之间的边界结构。此外,最近的发展表明,磁重联在日冕可能发生在高度分散的电流层,这通常会导致一个显着增加的拓扑结构的复杂性超出了平衡场。在本文中,我们研究了碎片电流层中开闭通量边界处重联(“交换重联”)的后果。我们证明,它导致的情况下,磁通量(因此等离子体)从开放和封闭的领域有效地混合在一起。这对应于开闭边界的长度和复杂性的增加。因此,每当重联发生在开闭边界的零点或分离器处时,高日冕中所谓的“S网”的相关分界线弧就变成不是单线而是有限厚度的带,在该带内开闭通量边界是高度结构化的。这对缓慢的太阳风的加速有着重要的意义,开放和封闭场的相互作用被认为是重要的,也可以解释某些太阳高能粒子的日冕起源。检查的拓扑结构包含磁零点,separatrices和分离器,并包括一个伪流光模型。同时也讨论了与日冕零相关的耀斑带中观测到的大尺度形态和精细结构的可能性。

英文摘要:

Global magnetic field extrapolations are now revealing the huge complexity of the Sun's corona, and in particular the structure of the boundary between open and closed magnetic flux. Moreover, recent developments indicate that magnetic reconnection in the corona likely occurs in highly fragmented current layers, and that this typically leads to a dramatic increase in the topological complexity beyond that of the equilibrium field. In this paper we investigate the consequences of reconnection at the open-closed flux boundary ("interchange reconnection") in a fragmented current layer. We demonstrate that it leads to a situation in which magnetic flux (and therefore plasma) from open and closed field regions is efficiently mixed together. This corresponds to an increase in the length and complexity of the open-closed boundary. Thus, whenever reconnection occurs at a null point or separator of the open-closed boundary, the associated separatrix arc of the so-called "S-web" in the high corona becomes not a single line but a band of finite thickness within which the open-closed flux boundary is highly structured. This has significant implications for the acceleration of the slow solar wind, for which the interaction of open and closed field is thought to be important, and may also explain the coronal origins of certain solar energetic particles. The topological structures examined contain magnetic null points, separatrices and separators, and include a model for a pseudo-streamer. The potential for understanding both the large scale morphology and fine structure observed in flare ribbons associated with coronal nulls is also discussed.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑