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arXiv · 2003.11747

A White-light Flare Powered by Magnetic Reconnection in the Lower Solar Atmosphere

Yongliang Song·Hui Tian·Xiaoshuai Zhu·Yajie Chen·Mei Zhang·Jingwen Zhang
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Abstract

White-light flares (WLFs), first observed in 1859, refer to a type of solar flares showing an obvious enhancement of the visible continuum emission. This type of enhancement often occurs in most energetic flares, and is usually interpreted as a consequence of efficient heating in the lower solar atmosphere through non-thermal electrons propagating downward from the energy release site in the corona. However, this coronal-reconnection model has difficulty in explaining the recently discovered small WLFs. Here we report a C2.3 white-light flare, which are associated with several observational phenomena: fast decrease in opposite-polarity photospheric magnetic fluxes, disappearance of two adjacent pores, significant heating of the lower chromosphere, negligible increase of hard X-ray flux, and an associated U-shaped magnetic field configuration. All these suggest that this white-light flare is powered by magnetic reconnection in the lower part of the solar atmosphere rather than by reconnection higher up in the corona.

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Yongliang Song, Hui Tian, Xiaoshuai Zhu, Yajie Chen, Mei Zhang, Jingwen Zhang. 2020-03-26. A White-light Flare Powered by Magnetic Reconnection in the Lower Solar Atmosphere. https://doi.org/10.3847/2041-8213/ab83fa

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