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Observational evidence for a different IMF in the early Galaxy

Sara Lucatello·Raffaele G. Gratton·Timothy C. Beers·Eugenio Carretta
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Abstract

The unexpected high incidence of carbon-enhanced, s-process enriched unevolved stars amongst extremely metal-poor stars in the halo provides a significant constraint on the Initial Mass Function (IMF) in the early Galaxy. We argue that these objects are evidence for the past existence of a large population of intermediate-mass stars, and conclude that the IMF in the early Galaxy was different from the present, and shifted toward higher masses.

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Sara Lucatello, Raffaele G. Gratton, Timothy C. Beers, Eugenio Carretta. 2004-12-16. Observational evidence for a different IMF in the early Galaxy. https://doi.org/10.1086/428105

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