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Ages of Galactic Globular Clusters from the New Yale Isochrones

Brian Chaboyer·P. Demarque·D. B. Guenther·M. H. Pinsonneault·L. L. Pinsonneault
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Abstract

A new grid of theoretical isochrones based on the Yale stellar evolution code using the OPAL and Kurucz opacities has been constructed. The grid of isochrones spans a wide range of metallicities, helium abundances and masses. The construction of the isochrones is described and the isochrones are compared to galactic globular cluster observations. A solar calibrated mixing length ($α= 1.7$) yields a good fit to globular cluster colour-magnitude diagrams. Ages for 40 globular clusters are determined using the \dv method and the formation of the halo is discussed.

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Brian Chaboyer, P. Demarque, D. B. Guenther, M. H. Pinsonneault, L. L. Pinsonneault. 1994-11-07. Ages of Galactic Globular Clusters from the New Yale Isochrones. https://arxiv.org/abs/astro-ph/9411024

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