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A contribution of 26Al to the O-Al anticorrelation in globular cluster red giants

Pavel A. Denissenkov·Achim Weiss
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Abstract

We modify our combined ("deep mixing" plus "primordial") scenario explaining the star-to-star abundance variations in globular cluster red giants in such a way that it confirms with new experimental data: (i) the new and better constrained (NACRE) thermonuclear reaction rates and (ii) a discovery of the O-Na anticorrelation in stars below the main-sequence turn-off in the cluster NGC6752. For the latter we propose that some main-sequence dwarfs in globular clusters accrete material lost by red giant primary components of close binaries during a common envelope event. As a consequence of the new reaction rates, we are drawn to the conclusion that the anomalies in [Al/Fe] in globular cluster red giants are in fact manifestations of 26Al (instead of the stable isotope 27Al) abundance variations produced by deep mixing.

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Pavel A. Denissenkov, Achim Weiss. 2001-07-11. A contribution of 26Al to the O-Al anticorrelation in globular cluster red giants. https://doi.org/10.1086/323789

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