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arXiv · 0711.0248

The link between chemical anomalies along the red giant branch and the horizontal branch extension in globular clusters

Eugenio Carretta·Alejandra Recio-Blanco·Raffaele G. Gratton·Giampaolo Piotto·Angela Bragaglia
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Abstract

We find a strong correlation between the extension of the Na-O anticorrelation observed in red giant branch (RGB) stars and the high temperature extension of the horizontal branch (HB) blue tails of Galactic globular clusters (GCs). The longer is the O-depleted tail of the Na-O anticorrelation observed in the RGB stars, the higher is the maximum temperature reached by the bluest HB stars in the GC. This result provides a clear, empirical evidence of a link between the extension of the HB and the presence of star-to-star abundance variations of proton-capture elements in GC stars. We discuss the possible interpretation of this correlation.

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Eugenio Carretta, Alejandra Recio-Blanco, Raffaele G. Gratton, Giampaolo Piotto, Angela Bragaglia. 2007-11-02. The link between chemical anomalies along the red giant branch and the horizontal branch extension in globular clusters. https://doi.org/10.1086/525021

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