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arXiv · 0905.2397

Evolutionary implications of the new triple-alpha nuclear reaction rate for low mass stars

Aaron Dotter·Bill Paxton
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Abstract

Context: Ogata et al. (2009; hereafter OKK) presented a theoretical determination of the triple-alpha nuclear reaction rate. Their rate differs from the NACRE rate by many orders of magnitude at temperatures relevant for low mass stars. Aims: We explore the evolutionary implications of adopting the OKK triple-alpha reaction rate in low mass stars and compare the results with those obtained using the NACRE rate. Methods: The triple-alpha reaction rates are compared by following the evolution of stellar models at 1 and 1.5 Msol with Z=0.0002 and Z=0.02. Results: Results show that the OKK rate has severe consequences for the late stages of stellar evolution in low mass stars. Most notable is the shortening--or disappearance--of the red giant phase. Conclusions: The OKK triple-alpha reaction rate is incompatible with observations of extended red giant branches and He burning stars in old stellar systems.

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Aaron Dotter, Bill Paxton. 2009-05-14. Evolutionary implications of the new triple-alpha nuclear reaction rate for low mass stars. https://doi.org/10.1051/0004-6361%2F200912998

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