A star hosting six terrestrial-type planets and showing intense X-ray emission, with a cyclic behavior on a timescale of about two years, which may have a significant impact on the properties of the planets and their atmospheres. The magnetic activity of a star manifests itself through a variety of high-energy phenomena that produce X-ray and UV radiation. Studying this
Flares are among the most energetic magnetic phenomena occuring in stars. They are triggered by a sudden release of energy previously stored in the stellar magnetic field, and then they culminate with the formation of magnetic loops in the stellar coronae filled by X-ray and UV emitting plasma at million degrees. Sometimes, these magnetic structures erupt, releasing in the surrounding
The corona is the outermost part of the atmosphere in stars with intermediate and low mass. In this region, which is extended for several stellar radii, the plasma can reach temperatures of several million degrees, emitting mainly X-ray radiation. The coronal temperature varies over a range of several orders of magnitude as a function of several stellar parameters, such as
