New empirical mass-loss recipe for UV radiation line-driven winds of hot stars across various metallicities

Vol. 697
8. Stellar atmospheres

New empirical mass-loss recipe for UV radiation line-driven winds of hot stars across various metallicities

Stellar winds from massive stars play a critical role in shaping their evolution and feedback, as they remove a substantial fraction of a star’s mass over its lifetime. In this study the authors present a homogeneous sample of nearly 200 hot stars (T > 12kK) across a broad metallicity range, each with well-constrained stellar and wind parameters. This sample is used to derive a physically motivated, empirically calibrated mass-loss prescription that is applicable to all hot stars. The newly derived mass-loss recipe depends only on the classical Eddington parameter and metallicity. Contrary to theoretical predictions, no clear evidence of a steep upturn in mass loss near the Eddington limit, nor a noticeable temperature dependence, can be found. The reported mass-loss relation yields mass-loss rates substantially lower than those from commonly used theoretical recipes. A first implementation of this new prescription in stellar evolution models highlights the importance of using accurate mass-loss rates by showing their impact on stellar evolution, feedback processes, and the final fates of massive stars.