Isochrones for α - element Enhanced Mixtures
نویسندگان
چکیده
We present a new set of isochrones in which the effect of the α-element enhancement is fully incorporated. These isochrones are an extension of the already published set of Y Isochrones (Yi et al. 2001: Paper 1), constructed for the scaled-solar mixture. As in Paper 1, helium diffusion and convective core overshoot have been taken into account. The range of chemical compositions covered is 0.00001 ≤ Z ≤ 0.08. The models were evolved from the pre-mainsequence stellar birthline to the onset of helium burning in the core. The age range of the full isochrone set is 0.1 – 20Gyr, while younger isochrones of age 1 – 80Myr are also presented up to the main-sequence turn-off. Combining this set with that of Paper 1 for scaled-solar mixture isochrones, we provide a consistent set of isochrones which can be used to investigate populations of any value
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