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arXiv · 1604.00485

Light Walls Around Sunspots Observed by the Interface Region Imaging Spectrograph

Y. J. Hou·T. Li·S. H. Yang·J. Zhang
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Abstract

The Interface Region Imaging Spectrograph (IRIS) mission provides high-resolution observations of the chromosphere and transition region. We try to determine whether the light walls exist somewhere else in active regions besides light bridges. Employing half-year high tempo-spatial data from the IRIS, we find lots of light walls either around sunspots or above light bridges. For the first time, we report one light wall near an umbral-penumbral boundary and another along a neutral line between two small sunspots. These new observations reveal that these light walls are multi-layer and multi-thermal structures which occur along magnetic neutral lines in active regions.

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Y. J. Hou, T. Li, S. H. Yang, J. Zhang. 2016-04-02. Light Walls Around Sunspots Observed by the Interface Region Imaging Spectrograph. https://doi.org/10.1051/0004-6361/201628216

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