GRB progenitors at low metallicities
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.
Keywords
Cite
@article{arxiv.astro-ph/0610276,
title = {GRB progenitors at low metallicities},
author = {R. Hirschi and G. Meynet and A. Maeder},
journal= {arXiv preprint arXiv:astro-ph/0610276},
year = {2010}
}
Comments
5 pages, 1 figure, to appear in the proceedings of "Swift and GRBs: Unveiling the Relativistic Universe", San Servolo, Venice, 5-9 June 2006