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arXiv · 1804.04673

ASASSN-18di: discovery of a $\Delta V \sim 10$ flare on a mid-M dwarf

Romy Rodríguez·Sarah J. Schmidt·Tharindu Jayasinghe·Krzysztof Z. Stanek·Jose L. Prieto·Benjamin Shappee·Chris S. Kochanek·Todd A. Thompson·Joshua Shields·Tom W. -S. Holoien·David Bersier·Joe Brimacombe
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Abstract

We report and characterize a white-light superflare on a previously undiscovered M dwarf detected by the ASAS-SN survey. Employing various color-magnitude and color-spectral type relationships, we estimate several stellar parameters, including the quiescent V-band magnitude, from which we derive a flare amplitude of $\Delta V \sim 10$. We determine an r-band absolute magnitude of $M_{r} = 11.4$, consistent with a mid-M dwarf, and an approximate distance to the source of $2.2$ kpc. Using classical-flare models, we infer a flare energy of $E_{V} \simeq (4.1\pm 2.2)\times 10^{36}$ ergs, making this one of the strongest flares documented on an M dwarf.

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Romy Rodríguez, Sarah J. Schmidt, Tharindu Jayasinghe, Krzysztof Z. Stanek, Jose L. Prieto, Benjamin Shappee, Chris S. Kochanek, Todd A. Thompson, Joshua Shields, Tom W. -S. Holoien, David Bersier, Joe Brimacombe. 2018-04-12. ASASSN-18di: discovery of a $\Delta V \sim 10$ flare on a mid-M dwarf. https://arxiv.org/abs/1804.04673

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