Activity evolution for F, G, K, and M dwarfs and the importance for planetary atmospheres

The magnetic activity of stars is a crucially important factor influencing planet formation processes and the subsequent evolution of planetary atmospheres. Understanding how stellar activity evolves for stars with different masses is crucially important for understanding the effects of stellar winds and radiation at X-ray and ultraviolet wavelengths on the erosion of circumstellar disks and planetary atmospheres. I will present a new and comprehensive description of the rotational evolution of stars and the resulting evolution of X-ray and ultraviolet emission for F, G, K, and M dwarfs. I will demonstrate the importance of the star's initial rotation rate on the subsequent activity evolution and clarify common misunderstandings regarding the dependence on stellar mass, including the common belief that M dwarfs are more XUV active than G dwarfs. I will show why these results are important for the evolution of planetary atmospheres.