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

TL;DR

This study analyzed long-term photometric data from 2000-2020 to detect optical flares on 12 G, K, and M dwarf stars, identifying numerous low-amplitude brightening events indicative of stellar flares.

Contribution

It presents a comprehensive analysis of flare activity on cool dwarfs using extensive ground-based photometric data, highlighting the prevalence and characteristics of optical flares.

Findings

Detected flares with brightness increases up to 0.5 mag.

Flares lasted from several minutes to under 3 hours.

Most probable flares are short-lived, around several minutes.

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.