Comunicazione
Stellar pulsation modeling of Classical Cepheids: new determinations of structural parameters and individual distances.
Molinaro R., Marconi M., De Somma G., Ripepi V., Musella I.
Classical Cepheids are intermediate-mass stars, burning helium in their core, characterized by the presence of radially pulsating motions, which cause their radial dimension to vary periodically, together with their luminosity and temperature. Studying these objects is interesting from two points of view: i) the existence of a correlation between their pulsational period and their luminosity makes them the most used standard candles within the range of standard candles used to calibrate the secondary distance indicators able to reach cosmological distances (above 100Mpc); ii) their pulsational properties make them a perfect "laboratory" to investigate the stellar interiors and to test the theories of stellar structure and evolution. Here, I will discuss the results obtained by comparing the model predictions of a nonlinear convective stellar pulsation code with the light and radial velocity data recently collected within the Gaia mission. Our model fitting technique allows us to estimate the structural parameters (Mass, Temperature, Luminosity) of the investigated Classical Cepheids, together with their individual distances that can be directly compared with Gaia astrometric results.