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Pre-supernova models at very low metallicity

R. Hirschi
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Abstract

A series of fast rotating models at very low metallicity (Z=1e-8) was computed in order to explain the surface abundances observed at the surface of CEMP stars, in particular for nitrogen. The main results are the following: - Strong mixing occurs during He--burning and leads to important primary nitrogen production. - Important mass loss takes place in the RSG stage for the most massive models. The 85 solar mass model loses about three quarter of its initial mass, becomes a WO star and could produce a GRB. - The CNO elements of HE1327-2326 could have been produced in massive rotating stars and ejected by their stellar winds.

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R. Hirschi. 2006-10-10. Pre-supernova models at very low metallicity. https://arxiv.org/abs/astro-ph/0610281

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