The period-age relation of long-period variables

Context. Pieces of empirical evidence suggest the existence a period-age relation for long-period variables (LPVs). Yet, this property has hardly been studied on theoretical grounds thus far. Aims. We aim to examine using results from recent nonlinear pulsation calculations. Methods. combined isochrone models with periods simulate distribution fundamental mode LPV pulsators, which include Miras, in plane, and we compared it observations LPVs Galactic Magellanic Clouds’ clusters. Results. In agreement observations, predict that period decreases increasing age because dominant role mass shaping stellar structure evolution. At given age, shows non-negligible width is skewed toward short periods, except young C-rich stars. As result, relations O-rich are predicted have different slopes. derived best-fit describing initial as function both O- models. Conclusions. The study confirms power populations specific types, either or C-rich, statistical grounds. doing so, recommended not limit would make prone selection biases, but rather semi-regular pulsate predominantly mode. use individual LPVs, other hand, requires more care scatter at any age.