Magnetism of solar-like stars through spot impact in light curves

Non-English characters and , and simple LaTeX math can be used e.g. "A star with mass $<1\times M_\odot$" The mechanisms behind stellar magnetism remain an open question in stellar physics : there is a huge variety of topologies and magnetic properties and scales. The link between these properties and stellar parameters (radius, mass, age, temperature, or Rossby number) are still elusive. The photometric activity is used here as an observable to improve our understanding of spot characteristics (area, lifetime…) and link these properties to the dynamo effect which rules all these phenomena. We propose to characterize this activity using the signature of spots in the light curves, seen in the Fourier domain. For this, we revisit the model of Harvey et al. (1985) in order to take into account all the components present in the power spectra. This method allows access to two proxies of the activity : the mean spot coverage and the lifetime of the spots. After validating this model with simulated light curves, we present the results from thousands of Kepler light curves of main sequence stars used by McQuillan (2014) and Santos (2022). The results show the emergence of three different regimes of activity related to different level of spot coverage and long or short spot lifetime. These regimes are linked to different stars properties such as their rotation period, mass and the Rossby number, which can provide information about the stellar dynamo evolution.