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arXiv · 1610.03104

Slender Ca II H Fibrils Mapping Magnetic Fields in the Low Solar Chromosphere

Shahin Jafarzadeh·R. J. Rutten·S. K. Solanki·T. Wiegelmann·T. Riethmueller·M. van Noort·M. Szydlarski·J. Blanco Rodriguez·P. Barthol·J. C. del Toro Iniesta·A. Gandorfer·L. Gizon·J. Hirzberger·M. Knoelker·V. Martinez Pillet·D. Orozco Suarez·W. Schmidt
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Abstract

A dense forest of slender bright fibrils near a small solar active region is seen in high-quality narrowband Ca II H images from the SuFI instrument onboard the Sunrise balloon-borne solar observatory. The orientation of these slender Ca II H fibrils (SCF) overlaps with the magnetic field configuration in the low solar chromosphere derived by magnetostatic extrapolation of the photospheric field observed with Sunrise/IMaX and SDO/HMI. In addition, many observed SCFs are qualitatively aligned with small-scale loops computed from a novel inversion approach based on best-fit numerical MHD simulation. Such loops are organized in canopy-like arches over quiet areas that differ in height depending on the field strength near their roots.

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Shahin Jafarzadeh, R. J. Rutten, S. K. Solanki, T. Wiegelmann, T. Riethmueller, M. van Noort, M. Szydlarski, J. Blanco Rodriguez, P. Barthol, J. C. del Toro Iniesta, A. Gandorfer, L. Gizon, J. Hirzberger, M. Knoelker, V. Martinez Pillet, D. Orozco Suarez, W. Schmidt. 2017-03-28. Slender Ca II H Fibrils Mapping Magnetic Fields in the Low Solar Chromosphere. https://doi.org/10.3847/1538-4365%2F229%2F1%2F11

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