# Probing the Origin of Stellar Flares on M dwarfs Using TESS Data Sectors 1-3

## TL;DR

This study uses TESS data to analyze the relationship between starspots and flares on low-mass M dwarf stars, finding no clear correlation between large starspots and flare occurrences, and providing detailed flare energy measurements.

## Contribution

It provides the first large-scale analysis of flare and starspot activity on low-mass stars using TESS data, revealing a lack of phase correlation between spots and flares.

## Key findings

- 90% of stars show rotational modulation due to starspots
- 1834 flares detected with energies up to 2.4×10^{35} erg
- No preferred rotational phase for flares observed

## Abstract

Detailed studies of the Sun have shown that sunspots and solar flares are closely correlated. Photometric data from Kepler/K2 has allowed similar studies to be carried out on other stars. Here, we utilise TESS photometric 2-min cadence of 167 low mass stars from Sectors 1 - 3 to investigate the relationship between starspots and stellar flares. From our sample, 90 percent show clear rotational modulation likely due to the presence of a large, dominant starspot and we use this to determine a rotational period for each star. Additionally, each low mass star shows one or more flares in its lightcurve and using Gaia DR2 parallaxes and SkyMapper magnitudes we can estimate the energy of the flares in the TESS band-pass. Overall, we have 1834 flares from the 167 low mass stars with energies from $6.0\times 10^{29}$ - $2.4\times 10^{35}$~erg. We find none of the stars in our sample show any preference for rotational phase suggesting the lack of a correlation between the large, dominant star spot and flare number. We discuss this finding in greater detail and present further scenarios to account for the origin of flares on these low mass stars.