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arXiv · astro-ph/0610276

GRB progenitors at low metallicities

R. Hirschi·G. Meynet·A. Maeder
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Abstract

We calculated pre-supernova evolution models of single rotating massive stars. These models reproduce observations during the early stages of the evolution very well, in particular Wolf--Rayet (WR) populations and ratio between type II and type Ib,c supernovae at different metallicities (Z). Using these models we found the following results concerning long and soft gamma--ray burst (GRB) progenitors: - GRBs coming from WO--type (SNIc) WR stars are only produced at low Z (LMC or lower). - The upper metallicity limit for GRBs is reduced to Z ~ 0.004 (SMC) when the effects of magnetic fields are included. - GRBs are predicted from the second (and probably the first) stellar generation onwards.

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R. Hirschi, G. Meynet, A. Maeder. 2006-10-10. GRB progenitors at low metallicities. https://doi.org/10.1393/ncb%2Fi2007-10237-6

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