Implementation of new OPAL tables in Eggleton's stellar evolution code

Abstract

Based on previous works of OPAL, we construct a series of opacity tables for various metallicities Z ≤ 0, 0.000 01, 0.000 03, 0.000 1, 0.000 3, 0.001, 0.004, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.08 and 0.1. These tables can be easily used in Eggleton's stellar evolution code in place of the old tables without changing the code. The OPAL tables are used for 3. 95$">log 10(T/K)>3.95 and Alexander's for log 10(T/K)<3.95. At log10(T/K) ≤ 3.95, the two groups' data fit well for all hydrogen mass fractions. Conductive opacities are included by reciprocal addition according to the formulae of Yakovlev and Urpin. A comparison of 1 and 5 M⊙ models constructed with the older OPAL tables of Iglesias and Rogers shows that the new opacities have most effect in the late stages of evolution, the extension of the blue loop during helium burning for intermediate-mass and massive stars.