Toward Better Age Estimates for Stellar Populations: The Y2 Isochrones for Solar Mixture

  title={Toward Better Age Estimates for Stellar Populations: The Y2 Isochrones for Solar Mixture},
  author={Sukyoung K. Yi and Pierre. Demarque and Y.-C. Kim and Y-W. Lee and Chang Hee Ree and Thibault Lejeune and Sydney A. Barnes},
  journal={Astrophysical Journal Supplement Series},
We have constructed a new set of isochrones, called the Y2 Isochrones, that represent an update of the Revised Yale Isochrones (RYI), using improved opacities and equations of state. Helium diffusion and convective core overshoot have also been taken into consideration. This first set of isochrones is for the scaled solar mixture. A subsequent paper will consider the effects of α-element enhancement, believed to be relevant in many stellar systems. Two additionally significant features of these… Expand
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