The corona is the outermost part of the atmosphere of the vast majority of stars, where the plasma is heated to millions of degrees by stellar magnetic activity. Since both the intensity and the topology of the stellar magnetic fields depend on the internal structure of stars, the study of coronal activity allows astronomers to better understand both the high-energy
Supernova remnants are clouds in rapid expansion formed by supernova explosions. Typically, these remnants are very inhomogeneous. These inhomogeneity is the result of the interaction between the expanding remnant and the surrounding material, and, in particular when they are generated by core-collapse supernova explosions (which are the supernova triggered by the gravitational collapse of the cores of massive stars), also to anisotropies formed
Stellar X-ray emission arises from their corona, which is the outer part of stellar atmosphere with low-density high-temperature (up to million degrees) plasma. Even if we lack a fully understanding of the details, we know that the intensity of stellar X-ray emission depends on the intensity and the morphology of stellar magnetic field. The interior of stars of FGK
