Stellar Evolution Through the Red Supergiant Phase

Massive stars less massive than $\sim$30\,{\msol} evolve into a red supergiant after the main sequence. Given a standard IMF, this means about 80\% of all massive stars will experience this phase. RSGs are dominated by convection, with a radius that extends to thousands of solar radii. Their low temperature and gravity make them prone to lose large amounts of masses, either through a pulsationally-driven wind or through mass-loss outburst. RSGs are the progenitors of the most common core-collapse supernovae, the type II. In the present review, we give an overview of our theoretical understanding about this spectacular phase of massive stars evolution.