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To Be or Not to Be: EHB Stars and AGB Stars

Published online by Cambridge University Press:  30 December 2019

David A. Brown*
Affiliation:
Specola Vaticana (Vatican Observatory), V-00120, Cittá del Vaticano, Vatican City State, Europe email: [email protected]
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Abstract

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The formation of EHB stars is linked to the lives of AGB stars by indications that such EHB/sdB stars might form in globular clusters with multiple populations linked to AGB evolution. Observations of massive globular clusters, such as ω-Centauri (Bedin et al.2004, Piotto et al.2005) suggest that single EHB stars might form from He-enhanced progenitors (D’Antona et al.2005, D’Antona & Caloi 2008, Lee et al.2005) in environments enriched by AGB ejecta. The studies conducted by Han et al. (2002), Han et al. (2003), and Han et al. (2007) have been able to provide a strong case for the binary formation of EHB/sdB stars in the Galactic field, though binary formation channels in globular clusters is uncertain. Simulations presented here are an extension of the simulations of Han et al. (2002) and Han et al. (2003), for low metallicities to examine the binary EHB population in globular clusters.

Type
Contributed Papers
Copyright
© International Astronomical Union 2019 

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