Metallicity-dependent wind parameter predictions for OB stars

ABSTRACT Mass-loss rates and terminal wind velocities are key parameters that determine the kinetic energy momenta of massive stars. Furthermore, accurate mass-loss mass rotational velocity evolution stars, their fates as neutron stars black holes in function metallicity (Z). Here, we update our Monte Carlo Recipe with new dynamically consistent computations – a Z. These predictions particularly timely Hubble Space Telescope Ultraviolet Legacy Library Young Stars Essential Standards (ULLYSES) project will observe ultraviolet spectra blue-shifted P Cygni lines hundreds low-Z Large Small Magellanic Clouds (SMC), well sub-SMC hosts. Around 35 000 K, uncover weak-wind ‘dip’ present diagnostics to investigate its physics ULLYSES X-Shooter data. We discuss how dip may provide important information on wind-driving physics, this is relevance towards finding gold-standard for OB star rates. For B supergiants below Fe iv iii bi-stability jump, found be independent Z M, while rate still varies $\dot{M} \propto Z^{0.85}$. O-type above jump we, find terminal-velocity dependence $\mbox{$v _{\infty }$}\propto Z^{0.19}$ Z-dependence shallow Z^{0.42}$, implying reproduce ‘heavy’ from LIGO/Virgo, ‘low Z’ requirement becomes even more stringent than was previously anticipated.