The puzzle of the CNO abundances of α Cygni variables resolved by the Ledoux criterion

@article{Georgy2014ThePO,
title={The puzzle of the CNO abundances of $\alpha$ Cygni variables resolved by the Ledoux criterion},
author={Cyril Georgy and Hideyuki Saio and Georges Meynet},
journal={Monthly Notices of the Royal Astronomical Society},
year={2014},
volume={439}
}
• Published 19 November 2013
• Physics
• Monthly Notices of the Royal Astronomical Society
Recent stellar evolution computations show that the blue supergiant (BSG) stars could come from two distinct populations: a first group arising from massive stars that just left the main sequence (MS) and are crossing the Hertzsprung-Russell diagram (HRD) towards the red supergiant (RSG) branch, and a second group coming from stars that have lost considerable amount of mass during the RSG stage and are crossing the HRD for a second time towards the blue region. Due to very different luminosity…

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