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arXiv · 0808.2722

Modelling the evolution and nucleosynthesis of carbon-enhanced metal-poor stars

O. R. Pols·R. G. Izzard·M. Lugaro·S. E. de Mink
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Abstract

We present the results of binary population simulations of carbon-enhanced metal-poor (CEMP) stars. We show that nitrogen and fluorine are useful tracers of the origin of CEMP stars, and conclude that the observed paucity of very nitrogen-rich stars puts strong constraints on possible modifications of the initial mass function at low metallicity. The large number fraction of CEMP stars may instead require much more efficient dredge-up from low-metallicity asymptotic giant branch stars.

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O. R. Pols, R. G. Izzard, M. Lugaro, S. E. de Mink. 2008-08-20. Modelling the evolution and nucleosynthesis of carbon-enhanced metal-poor stars. https://doi.org/10.1017/s1743921308023260

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