Published online by Cambridge University Press: 07 August 2017
We review the dynamics of Wolf-Rayet stellar winds, with emphasis on how multi-line scattering can lead to mass loss rates for which the wind's radial momentum flux Ṁv∞ greatly exceeds the limit for single-scattering of the star's radiative momentum L*/c. The geometrical considerations that allow this to occur are illuminated through connections to multiple scattering in an effectively gray medium. The so-called “WR wind momentum problem” would be better characterized as an “opacity problem” of simply identifying a sufficiently dense ensemble of optically thick lines.