The Red Supergiant Problem: Circumstellar dust as a solution

We investigate the red supergiant problem: the apparent dearth of Type IIP supernova progenitors with masses between 16 and 30 M_⊙. Although red supergiants with masses in this range have been observed, none have been identified as progenitors in pre-explosion images. We show that, by failing to take into account the additional extinction resulting from the dust produced in the red supergiant winds, the luminosity of the most massive red supergiants at the end of their lives is underestimated. We re-estimate the initial masses of all Type IIP progenitors for which observations exist and analyse the resulting population. We find that the most likely maximum mass for a Type IIP progenitor is 21⁺² _-1 M_⊙. This is in closer agreement with the limit predicted from single star evolution models.