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arXiv · 1609.01122

H-alpha features with hot onsets III. Fibrils in Lyman-alpha and with ALMA

Robert J. Rutten
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Abstract

In H-alpha most of the solar surface is covered by dense canopies of long opaque fibrils, but predictions for quiet-Sun observations with ALMA have ignored this fact. Comparison with Ly-alpha suggests that the large opacity of H-alpha fibrils is caused by hot precursor events. Application of a recipe that assumes momentary Saha-Boltzmann extinction during their hot onset to millimeter wavelengths suggests that ALMA will observe H-alpha-like fibril canopies, not acoustic shocks underneath, and will yield data more interesting than if these canopies were transparent.

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Robert J. Rutten. 2016-09-05. H-alpha features with hot onsets III. Fibrils in Lyman-alpha and with ALMA. https://doi.org/10.1051/0004-6361/201629238

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