<scp>parsec</scp>: stellar tracks and isochrones with the PAdova and TRieste Stellar Evolution Code

TLDR

The authors present an updated Padova stellar evolution code to supply the community with tools for modeling star clusters and galaxies via population synthesis. The code incorporates a comprehensive revision of input physics, adds pre‑main‑sequence evolution, generates composition‑consistent opacity tables by coupling OPAL and æsopus data, adopts the Caffau solar heavy‑element distribution, and produces isochrones in multiple photometric systems. Extended sets of stellar evolutionary models for various initial chemical compositions are presented, with additional sets for other metallicities and element distributions in progress.

Abstract

We present the updated version of the code used to compute stellar evolutionary tracks in Padova. It is the result of a thorough revision of the major input physics, together with the inclusion of the pre-main sequence phase, not present in our previous releases of stellar models. Another innovative aspect is the possibility of promptly generating accurate opacity tables fully consistent with any selected initial chemical composition, by coupling the Opacity Project At Livermore (OPAL) data at high temperatures to the molecular opacities computed with our æsopus code. In this work, we present extended sets of stellar evolutionary models for various initial chemical compositions, while other sets with different metallicities and/or different distributions of heavy elements are being computed. For the present release of models, we adopt the solar distribution of heavy elements from the recent revision by Caffau et al., corresponding to a Sun's metallicity Z ≃ 0.0152. From all computed sets of stellar tracks, we also derive isochrones in several photometric systems. The aim is to provide the community with the basic tools to model star clusters and galaxies by means of population synthesis techniques.