Stellar models for a wide range of initial chemical compositions until helium burning ^*

III. From X = 0.55 to X = 0.75, for Z = 0.03

Instituto de Astrofísica de Andalucía, CSIC, Apartado 3004, E-18080 Granada, Spain

Send offprint request to: A. Claret

Received: 28 October 1996
Accepted: 24 January 1997

Abstract

In this Paper I present grids for the stellar models with a slightly higher metallic content than in the previous works (Claret 1995; Claret & Giménez 1995), say, . The initial helium abundances in mass are , 0.32 and 0.22; this last value was used only to facilitate interpolations since it is a little bit smaller than the primordial helium abundance. The present computations are based on the radiative opacities with spin-orbit coupling provided by the Lawrence Livermore group (Iglesias et al. 1992). For the lower temperatures I have used the results by Alexander (1992). Core overshooting was taken into account as well as mass loss. The models presented here cover the mass range between 1 and . I also compute for all models the internal structure constants k_j and the radius of gyration β. For the first time the calculation of the tidal constants E₂ and , which are used to evaluate circularization and synchronization times in binary stars, are presented for stellar models as a function of the initial mass and time. The former is related with the dynamical tidal contribution to the total perturbed potential in a binary star while the latter is connected with the external structure of the outer layers.