PERICLES : A Set of Empirical Rotational Isochrones Modeled on Cool Dwarfs in Open Clusters and Wide Binaries

Isochrones, equal‐age curves, are widely used in astrophysics to estimate stellar ages. Classical stellar parameters are, however, very limited in their usability for main sequence stars because of their weak age‐dependence. Here, rotation period measurements provide complementary information. We construct and present a set of rotational isochrones, named the Potsdam Empirical Rotational Isochrones from CLustEr Stars ( Pericles ), that leverage rotation periods. They are constructed empirically using stars in well‐studied open clusters and a small number of complementary field stars. The rotational isochrones span the main sequence stars from late‐F type near the Kraft break to the fully‐convective boundary around M3 stars, and are available for ages ≤ 6 Gyr. We also discuss a limitation to such color‐ or temperature based rotational isochrones, together with ideas to overcome it.