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An updated theoretical scenario for Classical Cepheids in the Gaia Era.
De Somma G., Marconi M., Cassisi S., Ripepi V., Musella I.
Modeling of radially pulsating stars, specifically Classical Cepheids, is fundamental for constraining the extragalactic distance scale. The various ingredients entering the theoretical calibration of the CC distance scale can affect the accuracy of the inferred distances and, as such, cast light on residual systematics in the local determination of the Hubble constant in the context of the debated topic known as the Hubble constant tension. By extending the set of nonlinear convective pulsation models published for solar metallicity ($Z=0.02$, De Somma $et al.$, 2020) to $Z = 0.004$, $Z = 0.008$ and $Z = 0.03$, we provided a detailed homogeneous nonlinear model grid by varying the mass-luminosity (ML) relation, the efficiency of super-adiabatic convection and the chemical composition. As such, a multi-band light curve atlas was produced and period-luminosity-color (PLC), period-Wesenheit (PW) and metal-dependent PW relations for all the assumed assumptions were derived. The derived metal-dependent PW relations were compared with similar results in the literature and applied to a sample of Gaia EDR3 Galactic Cepheids with known metal abundances, so as to estimate their individual distance.