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arXiv · 1911.10859

A Hot Cusp-Shaped Confined Solar Flare

Aaron Hernandez-Perez·Yang Su·Julia K. Thalmann·Astrid M. Veronig·Ewan C. Dickson·Karin Dissauer·Bhuwan Joshi·Ramesh Chandra
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Abstract

We analyze a confined flare that developed a hot cusp-like structure high in the corona (H ~ 66 Mm). A growing cusp-shaped flare arcade is a typical feature in the standard model of eruptive flares, caused by magnetic reconnection at progressively larger coronal heights. In contrast, we observe a static hot cusp during a confined flare. Despite an initial vertical temperature distribution similar to that in eruptive flares, we observe a distinctly different evolution during the late (decay) phase, in the form of prolonged hot emission. The distinct cusp shape, rooted at locations of non-thermal precursor activity, was likely caused by a magnetic field arcade that kinked near the top. Our observations indicate that the prolonged heating was a result of slow local reconnection and an increased thermal pressure near the kinked apexes due to continuous plasma upflows.

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Aaron Hernandez-Perez, Yang Su, Julia K. Thalmann, Astrid M. Veronig, Ewan C. Dickson, Karin Dissauer, Bhuwan Joshi, Ramesh Chandra. 2019-11-25. A Hot Cusp-Shaped Confined Solar Flare. https://doi.org/10.3847/2041-8213%2Fab5ba1

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