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This is the result of a thorough revision and update of the stellar evolution code used in Padova to compute sets of stellar evolutionary tracks that are widely used by the astronomical community ( Bressan et al. In this paper, we briefly describe our new stellar evolution code parsec: the PAdova and TRieste Stellar Evolution Code. Stars: evolution, Hertzsprung‒Russell and colour magnitude diagrams, stars: interiors, stars: low-mass Introduction
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The aim is to provide the community with the basic tools to model star clusters and galaxies by means of population synthesis techniques.
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From all computed sets of stellar tracks, we also derive isochrones in several photometric systems. 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. 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. 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. 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. We present the updated version of the code used to compute stellar evolutionary tracks in Padova.