Stellar flares, superflares and coronal mass ejections -- entering the Big data era

TL;DR

This paper reviews stellar flares, superflares, and CMEs in the context of the Big Data era, highlighting new observational results and their implications for stellar magnetic activity models.

Contribution

It compiles recent observational findings from space photometry that challenge traditional solar-based flare models, emphasizing the impact of Big Data on stellar activity studies.

Findings

Diverse stellar types exhibit flare activity.

Observation strategies have evolved with Big Data.

Some results challenge the solar paradigm of flare models.

Abstract

Flares, sometimes accompanied by coronal mass ejections (CMEs), are the result of sudden changes in the magnetic field of stars with high energy release through magnetic reconnection, which can be observed across a wide range of the electromagnetic spectrum from radio waves to the optical range to X-rays. In our observational review, we attempt to collect some fundamental new results, which can largely be linked to the Big data era that has arrived due to the expansion of space photometric observations of the last two decades. We list the different types of stars showing flare activity, their observation strategies, and discuss how their main stellar properties relate to the characteristics of the flares (or even CMEs) they emit. Our goal is to focus, without claiming to be complete, on those results that may in one way or another challenge the "standard" flare model based on the solar paradigm.