New theoretical Mass-loss rates of O and B Stars

TL;DR

This paper presents new theoretical mass-loss rates for O and B stars, showing good agreement with observations for O stars and highlighting discrepancies in B star measurements, with implications for stellar evolution modeling.

Contribution

The study introduces a new theoretical mass-loss recipe for O and B stars that accounts for multiple scattering and bi-stability jumps, improving agreement with observations.

Findings

Good agreement between theoretical and observed mass-loss rates for O stars.

Discrepancies exist between different observational methods for B star mass-loss rates.

The new recipe is recommended for use in stellar evolution calculations.

Abstract

We have calculated mass-loss rates for a grid of wind models covering a wide range of stellar parameters and have derived a mass-loss recipe for two ranges of effective temperature at either side of the bi-stability jump around spectral type B1. For a large sample of O stars, it is shown that there is now good agreement between these new theoretical mass-loss rates that take multiple scattering into account and observations. Agreement between the observed and new theoretical wind momenta increases confidence in the possibility to derive distances to luminous stars in distant stellar systems using the Wind momentum Luminosity Relation. For the winds of the B stars there is an inconsistency in the literature between various mass-loss rate determinations from observations by different methods. One group of the determinations for B stars does follow the new theoretical relation, while another group does not. The lack of agreement between the observed mass-loss rates derived by different methods may point to systematic errors in mass-loss determinations from observations for B stars. We show that our theoretical mass-loss recipe is reliable and recommend it be used in evolutionary calculations.