EVOLUTIONARY STELLAR MODELS WITH CORE OVERSHOOTING AND MASS-LOSS - APSIDAL MOTION CONSTANTS

A new grid of evolutionary stellar models with core overshooting and mass loss is presented. In addition to these two physical mechanisms, new opacity Tables from Los Alamos Opacity Library were used, the chemical composition was adopted to be (X, Z) = (0.70, 0.02) and the mixing-length parameter was fixed to 2.0. The computed evolutionary tracks cover the mass range from 1.12 up to 25 m.. Models with about 300 layers inside the stellar configuration were calculated from the zero-age main sequence until the ignition of helium in the core. The first three harmonics of the stellar internal structure (k2, k3 and k4) needed for apsidal motion studies in close binaries are given for the first time in this kind of models. The new physical mechanisms introduced are found to be responsible for structures significantly more centrally concentrated in mass than previous models. Differences are estimated in around 0.10, in log k2, for a typical case.