Magnetic activity evolution on the main sequence from the Kepler observations

The knowledge of the evolution of rotation and magnetic activity of solar-like stars is key to understand our Sun. This was indeed realized several decades ago with the Mount Wilson spectroscopic survey where the goal was to characterize the magnetism of stars other than the Sun in order to put it into context and in time. By investigating the magnetic activity of other stars in a different parameter space, we can provide additional constraints to dynamo models as a function of stellar age and spectral type. While several surveys followed the Mount Wilson one, the number of stars that can be followed from the ground is quite limited. The recent catalog of rotation periods and photometric magnetic activity proxies for more than 55,000 stars observed by the Kepler mission opens the possibility to study the evolution of surface magnetic activity of a much larger sample of solar-like stars. We will present a sample of main-sequence stars where we compare the Sun to Sun-like stars. We also find that the magnetic activity of the Sun is comparable to the one of stars with properties very similar to the Sun. We also compute ages based on models that take into account the weakened magnetic braking theory observed in the Kepler asteroseismic sample. This allows us to study the evolution of magnetic activity as a function of age, providing a more complete picture to understand the dynamical changes on the main sequence.