Tuesday, October 25, 2011

1110.5049 (Sylvia Ekström et al.)

Grids of stellar models with rotation - I. Models from 0.8 to 120 Msun at solar metallicity (Z = 0.014)    [PDF]

Sylvia Ekström, Cyril Georgy, Patrick Eggenberger, Georges Meynet, Nami Mowlavi, Aurélien Wyttenbach, Anahí Granada, Thibaut Decressin, Raphael Hirschi, Urs Frischknecht, Corinne Charbonnel
[abridged] Many topical astrophysical research areas, as the properties of planet host stars, the nature of the progenitors of different types of supernovae and of gamma ray bursts, the evolution of galaxies, require, in order to be studied during the whole cosmic history, complete and homogeneous sets of stellar models at different metallicities. We present here a first set of models for solar metallicity, where the effects of rotation are accounted for in a homogeneous way. We computed a grid of 48 different stellar evolutionary tracks, both rotating and non-rotating, at Z=0.014, spanning a wide mass range from 0.8 to 120 Msun. For each of the stellar masses considered, electronic tables provide data for 400 stages along the evolutionary track and at each stage, 43 different physical data are given. These grids thus provide an extensive and detailed data basis for comparisons with the observations. The rotating models start on the ZAMS with a rotation rate Vini/Vcrit=0.40. The evolution is computed until the end of the central carbon-burning phase, the early AGB phase, or the core helium-flash for respectively the massive, intermediate, low and very low mass stars. The initial abundances are those which best fit the observed abundances of massive stars in the solar neighbourhood and correspond to the solar abundances as deduced by Asplund and collaborators. Opacities and nuclear reactions rates are updated. New prescriptions for the mass loss rates are introduced in particular when stars approach the Eddington and/or the critical velocity. Atomic diffusion and magnetic braking are accounted for in low-mass star models. [...]
View original: http://arxiv.org/abs/1110.5049

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