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The Wolf-Rayet hydrogen puzzle -- an observational point of view

C. Foellmi·S. V. Marchenko·A. F. J. Moffat
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Abstract

Significant amounts of hydrogen were found in very hot early-type single WN stars in the SMC and the LMC. Recently, we found similar evidence in the Wolf-Rayet star of a short-period LMC binary. We discuss here the relevance of hydrogen for WR star classification, models, the relation to metallicity, and the GRB progenitors.

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C. Foellmi, S. V. Marchenko, A. F. J. Moffat. 2005-10-20. The Wolf-Rayet hydrogen puzzle -- an observational point of view. https://arxiv.org/abs/astro-ph/0510612

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