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arXiv · 1705.01776

Binarity as the solution to the stellar evolution enigma posed by NGC 6791

Giovanni Carraro·Omar G. Benvenuto
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Abstract

Binary evolution is investigated as the source for the extreme horizontal branch (EHB) stars in the old and metal rich open cluster NGC~6791. Employing an updated version of our binary stellar evolution code we demonstrate that EHB stars naturally emerge from the common envelope phase. In sum, the binary model reproduces the observed ($T_{\rm{eff}}$, $\log{g}$) and temporal properties of the EHB over-density tied to NGC 6971, without needing an ad-hoc and anomalous mass-loss prescription.

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Giovanni Carraro, Omar G. Benvenuto. 2017-05-04. Binarity as the solution to the stellar evolution enigma posed by NGC 6791. https://doi.org/10.3847/2041-8213/aa7131

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