On the Theoretical Period-Radius Relation of Classical Cepheids
نویسندگان
چکیده
We present the results of a comprehensive theoretical investigation on the Period-Radius (PR) relation of classical Cepheids based on new sequences of full amplitude, nonlinear convective models constructed by adopting a wide range of both stellar masses and chemical compositions. In the period range 0.9 ≤ logP ≤ 1.8 a very good agreement is found between theoretical predictions and current available data whereas outside this range, both at shorter and at longer periods, nonlinear radii attain intermediate values between empirical relations based on different Baade-Wesselink (BW) methods and photometric bandpasses. Subject headings: Cepheids — galaxies: stellar content — stars: fundamental parameters — stars: oscillations Osservatorio Astronomico di Trieste, Via G. B. Tiepolo 11, 34131 Trieste, Italy; [email protected] Osservatorio Astronomico di Capodimonte, Via Moiariello 16, 80131 Napoli, Italy; [email protected] Dipartimento di Fisica, Univ. di Pisa, Piazza Torricelli 2, 56126 Pisa, Italy; [email protected]
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