The Wolf-Rayet hydrogen puzzle -- an observational point of view
arXiv:astro-ph/0510612
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.
5 pages, 2 figures, to appear in proc. of the Tartu Workshop, PASP, eds. Lamers, Langer, Nugis, Annuk