Theoretical wind clumping predictions from 2D LDI models of O-star winds at different metallicities

Hot, massive (OB) stars experience strong line-driven stellar winds and mass loss. As the majority of efficient driving lines are metallic, amount wind loss is dependent on metallicity Z. In addition, intrinsically inhomogeneous clumpy. However, to date, neither theoretical nor empirical studies have investigated how such clumping may also depend We theoretically degree due line-deshadowing instability (LDI) as a function performed two-dimensional hydrodynamic simulations LDI with an assumed one-dimensional radiation line force for grid O-star models fixed luminosity, but different metal contents by varying accumulative strength Qbar describing total ensemble lines. find that, this decreases metallicity. The decrease clearly seen in statistical properties our simulations, nonetheless rather weak; simple power-law fit dependence factor f_cl = /^2 yields ~ Z^(0.15 +/- 0.01). This implies that empirically derived dependencies mass-loss rate Mdot -- which were previously inferred from spectral diagnostics effectively depending Mdot*sqrt(f_cl) without having any constraints f_cl(Z) should be only modestly altered clumping. expect prediction can directly tested using new data Hubble Space Telescope Ultraviolet Legacy Library Young Stars Essential Standards (ULLYSES) project.