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Carbon Isotopic Abundances in the Red Giants of Omega Centauri (NGC5139)

Verne V. Smith·Donald M. Terndrup·Nicholas B. Suntzeff
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Abstract

Carbon-12 and carbon-13 abundances are measured in eleven red-giant members of the globular cluster Omega Centauri via observations of first-overtone CO bands near 2.3 microns. The mean value for the entire sample is <12C/13C>= 4.3 +/-0.4, with nine giants equal, within the errors, to the equilibrium ration of 12C/13C= 3.5. No correlation is found within Omega Cen between 12C/13C and the abundance of iron. The relation between 12C/13C and other abundance ratios, such as [O/Fe], {Na/Fe], or [Al/Fe] are also discussed.

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Verne V. Smith, Donald M. Terndrup, Nicholas B. Suntzeff. 2002-07-19. Carbon Isotopic Abundances in the Red Giants of Omega Centauri (NGC5139). https://doi.org/10.1086/342921

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