Advance in the Research of Stellar Superflares

Abstract

The Solar flare is one of the most violent eruptive phenomena in the Solar system, which releases energy up to ${10}^{25}$ J in tens of minutes. With the development of observational techniques, similar flare events have been observed on stars, with typical energy of 10 to ${10}^4$ times that of Solar flares, which is known as the superflare. Studies of stellar superflares and their mechanisms are not only important for understanding the internal structure, evolution, and magnetic activities of stars, but also for exploring the habitability and extraterrestrial life on exoplanets. A brief introduction is first given on Solar flares and the associated phenomena of magnetic activities, stellar magnetic field, and superflares of stars. Then, current detection methods and research results of stellar superflares are reviewed in terms of selection, energy evaluation, starspots, and the statistical relationships between the flare parameters and stellar parameters. Meanwhile, a comparison is made with the theories of Solar flares and the related physical processes to explore their similarities and connections. Finally, a summary is made and the related further work is also discussed.