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arXiv · 2207.09224

Detection of Optical Flares on the Selected G-M Dwarfs from Long-term Photometric Series

N. I. Bondar'·M. M. Katsova·A. A. Shlyapnikov
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Abstract

We have carried out a search for flares from the analysis of light curves for 12 active G, K, and M dwarfs. As sources of data we used ground-based observations in 2000-2020 from the photometric databases ASAS, SuperWASP, KWS. Events of low-amplitude brightening (Delta V < 0.25 mag), which possibly could be flares, were revealed for 11 stars. A large number of such increases in brightness were found on K dwarfs. Events of increasing in V-magnitudes to 0.5 mag or more were detected on light curves of one G star, BE Cet, and two M dwarfs. For three flares we could follow their development with time. We have estimated the duration of these flares; they lasted more than an hour, but less than 3 hours. In most cases we could not determine a lifetime of the suggested flares, but we believe that most of the probable flares on the investigated cool dwarfs are short-lived, on the order of several minutes.

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N. I. Bondar', M. M. Katsova, A. A. Shlyapnikov. 2022-07-19. Detection of Optical Flares on the Selected G-M Dwarfs from Long-term Photometric Series. https://doi.org/10.1134/s0016793221070057

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