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How did the metals in a giant star originate?

Piercarlo Bonifacio·Marco Limongi·Alessandro Chieffi
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Abstract

The chemical composition of stars with extremely low metal contents (taking ``metals'' to mean all elements other than hydrogen and helium) provides us with information on the masses of the stars that produced the first metals. Such a direct connection is not possible, however, if the surface of the star has been polluted by enriched material, either dredged from the star's interior or transferred from a companion star. Here we argue that, in the case of HE0107-5240 (ref. 1), the most iron poor star known, the oxygen abundance could be a discriminant: a ratio of [O/Fe] exceeding +3.5 would favour a pristine origin of metals, whereas an [O/Fe] ratio of less than +3 would favour the pollution hypothesis. Using this criterion, we suggest how the required information on oxygen abundance might be obtained.

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Piercarlo Bonifacio, Marco Limongi, Alessandro Chieffi. 2003-04-23. How did the metals in a giant star originate?. https://doi.org/10.1038/422834a

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