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The Chemical Evolution of Helium in Globular Clusters: Implications for the Self-Pollution Scenario

Amanda Karakas·Yeshe Fenner·Alison Sills·Simon Campbell·John Lattanzio
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Abstract

We investigate the suggestion that there are stellar populations in some globular clusters with enhanced helium (Y from 0.28 to 0.40) compared to the primordial value. We assume that a previous generation of massive Asymptotic Giant Branch (AGB) stars have polluted the cluster. Two independent sets of AGB yields are used to follow the evolution of helium and CNO using a Salpeter initial mass function (IMF) and two top-heavy IMFs. In no case are we able to produce the postulated large Y ~ 0.35 without violating the observational constraint that the CNO content is nearly constant.

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Amanda Karakas, Yeshe Fenner, Alison Sills, Simon Campbell, John Lattanzio. 2006-08-17. The Chemical Evolution of Helium in Globular Clusters: Implications for the Self-Pollution Scenario. https://doi.org/10.1086/508504

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