Speaker
Description
The most massive stars provide an essential source of recycled material for young clusters and galaxies. While very massive stars (VMS, M > 100M$_{\odot}$) are relatively rare compared to O stars, they lose disproportionately large amounts of mass already from the onset of core H-burning. In this talk, I will discuss the impact of stellar wind yields from VMS, calculated for a wide range of masses (50−500M$_{\odot}$). I will present chemical yields for metallicities ranging from Z$_{\odot}$ down to 1% solar metallicity, using the MESA stellar evolution code with updated mass-loss prescriptions. We find that for VMS at solar metallicity, 95% of the total wind yields are produced already on the main sequence, while only ∼ 5% is supplied by the post-main sequence. With optically-thick winds, these VMS eject significant quantities of H-burning products such as $^{14}$N, $^{20}$Ne, $^{23}$Na, and $^{26}$Al. At low metallicity, VMS can also produce Na-enriched and O-depleted material which is key for the observed anti-correlations in globular clusters.
