The Updated BaSTI Stellar Evolution Models and Isochrones: I. Solar Scaled Calculations

TL;DR

This paper introduces an updated BaSTI stellar evolution model and isochrone library with new physics inputs, covering a wide range of stellar masses, compositions, and ages, and validated against observations.

Contribution

The paper provides a comprehensive update to the BaSTI models, including new physics inputs, expanded parameter coverage, and asteroseismic properties, with public availability.

Findings

Models agree well with independent databases

Isochrones match observed stellar populations

Asteroseismic predictions are consistent with data

Abstract

We present an updated release of the BaSTI (a Bag of Stellar Tracks and Isochrones) stellar model and isochrone library for a solar scaled heavy element distribution. The main input physics changed from the previous BaSTI release include the solar metal mixture, electron conduction opacities, a few nuclear reaction rates, bolometric corrections, and the treatment of the overshooting efficiency for shrinking convective cores. The new model calculations cover a mass range between 0.1 and 15 Msun, 22 initial chemical compositions between [Fe/H]=-3.20 and +0.45, with helium to metal enrichment ratio dY /dZ=1.31. The isochrones cover an age range between 20 Myr and 14.5 Gyr, take consistently into account the pre-main sequence phase, and have been translated to a large number of popular photometric systems. Asteroseismic properties of the theoretical models have also been calculated. We compare our isochrones with results from independent databases and with several sets of observations, to test the accuracy of the calculations. All stellar evolution tracks, asteroseismic properties and isochrones are made available through a dedicated Web site.