The Horizontal Internetwork Magnetic Field: Numerical Simulations in Comparison to Observations with Hinode
The Horizontal Internetwork Magnetic Field: Numerical Simulations in Comparison to Observations with Hinode
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DOI：
10.1086/589740
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发表时间：
2008-01
期刊：
影响因子：
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通讯作者：
O. Steiner;R. Rezaei;W. Schaffenberger;S. Wedemeyer-Böhm
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文献类型：
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作者：
O. Steiner;R. Rezaei;W. Schaffenberger;S. Wedemeyer-Böhm
日野空间天文台的观测导致在安静的相互网络区域的光球层中发现了主要的水平磁场。在这里，我们研究了太阳表层相对于水平磁场的真实数值模拟，并计算了相应的Fe I 630 nm线对的极化响应。我们发现水平场分量的平均强度在大约500 km的光球高度处有一个局部最大值，根据初始状态或边界条件，它比垂直分量高出2.0或5.6倍。根据合成的Stokes剖面，根据初始状态或边界条件，我们推导出平均水平场分量比垂直分量强1.6或4.3倍。这是由于固有的更强的磁通密度和更大的面积被水平场占据的结果。我们发现，对流过冲将水平场驱逐到上层光球，使光球中的坡印亭通量为正，而其下方对流不稳定层中的坡印亭通量为负。
Observations with the Hinode space observatory led to the discovery of predominantly horizontal magnetic fields in the photosphere of the quiet internetwork region. Here we investigate realistic numerical simulations of the surface layers of the Sun with respect to horizontal magnetic fields and compute the corresponding polarimetric response in the Fe I 630 nm line pair. We find a local maximum in the mean strength of the horizontal field component at a height of around 500 km in the photosphere, where, depending on the initial state or the boundary condition, it surpasses the vertical component by a factor of 2.0 or 5.6. From the synthesized Stokes profiles, we derive a mean horizontal field component that is 1.6 or 4.3 times stronger than the vertical component, depending on the initial state or the boundary condition. This is a consequence of both the intrinsically stronger flux density of and the larger area occupied by the horizontal fields. We find that convective overshooting expels horizontal fields to the upper photosphere, making the Poynting flux positive in the photosphere, whereas the Poynting flux is negative in the convectively unstable layer below it.