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arXiv · 1912.05549

A Catalog of M-dwarf Flares with ASAS-SN

Romy Rodríguez Martínez·Laura A. Lopez·Benjamin J. Shappee·Sarah J. Schmidt·Tharindu Jayasinghe·Christopher S. Kochanek·Katie Auchettl·Thomas W. -S. Holoien
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Abstract

We analyzed the light curves of 1376 early-to-late, nearby M dwarfs to search for white-light flares using photometry from the All-Sky Automated Survey for Supernovae (ASAS-SN). We identified 480 M dwarfs with at least one potential flare employing a simple statistical algorithm that searches for sudden increases in $V$-band flux. After more detailed evaluation, we identified 62 individual flares on 62 stars. The event amplitudes range from $0.12 <ΔV < 2.04$ mag. Using classical-flare models, we place lower limits on the flare energies and obtain $V$-band energies spanning $2.0\times10^{30} \lesssim E_{V} \lesssim 6.9\times10^{35}$ erg. The fraction of flaring stars increases with spectral type, and most flaring stars show moderate to strong H$α$ emission. Additionally, we find that 14 of the 62 flaring stars are rotational variables, and they have shorter rotation periods and stronger H$α$ emission than non-flaring rotational variable M dwarfs.

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Romy Rodríguez Martínez, Laura A. Lopez, Benjamin J. Shappee, Sarah J. Schmidt, Tharindu Jayasinghe, Christopher S. Kochanek, Katie Auchettl, Thomas W. -S. Holoien. 2019-12-11. A Catalog of M-dwarf Flares with ASAS-SN. https://doi.org/10.3847/1538-4357%2Fab793a

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