Astrophysics of "extreme" solar-like stars

TL;DR

This paper discusses the astrophysics of superflares on red dwarf stars, analyzing recent optical and X-ray observations to understand their properties and potential impact, while highlighting the unknown origins of these powerful events.

Contribution

It provides a detailed analysis of a specific superflare event on DG CVn, offering insights into the emission evolution and properties of superflares on red dwarf stars.

Findings

Superflares are powerful, high-energy events on red dwarf stars.

The 2014 DG CVn superflare showed significant optical and X-ray emission evolution.

The origin of superflares remains unknown, requiring further investigation.

Abstract

Only a few red dwarf flaring stars in the solar neighbourhood have undergone exceptional events called superflares. They have been detected with high-energy satellites (i.e. Swift) and have been proven to be powerful events (both in intensity and energy) and potentially hazardous for any extraterrestial life. The physics of these events can be understood as an extrapolation of the (much) weaker activity already occurring in the most powerful solar flares occurring in the Sun. Nevertheless, the origin (why?) these superflares occur is currently unknown. A recent study presents the optical and X-ray long-term evolution of the emission by the super-flare from the red-dwarf star DG CVn undertaken in 2014. In that paper we comment on the context of these observations and on the properties that can be derived through the analysis of them.