The BaSTI Stellar Evolution Database: models for extremely metal-poor and super-metal-rich stellar populations

TL;DR

This paper extends the BaSTI stellar evolution database to include extremely metal-poor and super-metal-rich models, enabling studies of diverse stellar populations in the Local Group and Galactic bulge.

Contribution

The authors provide new stellar evolution tracks and isochrones for extreme metallicities, broadening the applicability of the BaSTI database for diverse astrophysical research.

Findings

New models for Z=10^{-5} and Z=0.05 metallicities are introduced.

Comparisons with existing literature validate the new models.

The extended database supports studies of metal-poor dwarf galaxies and the Galactic bulge.

Abstract

We present an extension of the BaSTI stellar evolution database to extremely metal poor (${\rm Z=10^{-5}}$) and super-metal-rich (Z=0.05) metallicities, with both scaled-solar and $\alpha$-enhanced ([$\alpha$/Fe]=0.4) heavy element distributions. These new tracks (from the pre-main sequence to the early-asymptotic giant branch phase), horizontal branch models and isochrones, will enable the use of the BaSTI database to study, i.e., the most metal poor populations found in Local Group faint dwarf galaxies, and the metal rich component of the Galactic bulge. An overview of several fundamental predictions of stellar evolution over the full metallicity range of BaSTI is presented, together with comparisons with literature calculations at ${\rm Z=10^{-5}}$ and Z=0.05.