How the mass-loss rates of red-supergiants determine the fate of massive stars ?

Mass-loss rates are one of the most relevant parameters determining the evolution of massive stars. In particular, the rates at which the star loses mass during the red-supergiant (RSG) phase is the least constrained by the observations or theory. In this paper, we show how the mass loss during the RSG phase affects the later evolution of the star, as well as the final type of supernova towards which it leads. We also discuss some possibilities to discriminate between blue stars that went through a RSG phase and those which remained in the blue part of the Hertzsprung-Russell diagram.
Comment: 9 pages, 3 figures, to be published in the proceedings of the Betelgeuse workshop held in Paris (November 2012) (EAS Publications Series)