(shortened) The first couple of stellar generations may have been massive, oforder 100 Msun, and to have played a dominant role in galaxy formation and thechemical enrichment of the early Universe. Some fraction of these objects mayhave died as pair-instability supernovae or gamma-ray bursts. The winds ifthese stars may have played an important role in determining these outcomes. Asthe winds are driven by radiation pressure on spectral lines, their strengthsare expected to vary with metallicity. Until now, most mass-loss predictionsfor metal-poor O-type stars have assumed a scaled-down solar-abundance pattern.However, Population III evolutionary tracks show significant surface enrichmentthrough rotational mixing of CNO-processed material, because even metal-poorstars switch to CNO-burning early on. We address the question of whether theCNO surface enhanced self-enrichment in the first few generations of starscould impact their mass-loss properties. For this, we employ Monte Carlosimulations to establish the local line-force and solve for the momentumequation of the stellar outflow, testing whether an outflow can actually beestablished by assessing the net acceleration at the sonic point of the flow.Stellar evolution models of rotating metal-poor stars are used to specify thesurface chemical composition, focussing on the phases of early enrichment. Wefind that the mass-loss rates of CNO enhanced metal-poor stars are higher thanthose of non-enriched stars, but they are much lower than those rates where theCNO abundance is included in the total abundance Z. We present a heuristicformula that provides mass-loss estimates for CNO-dominated winds in relationto scaled-down solar abundances.
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