Carbon and oxygen isotopic ratios in Arcturus and Aldebaran - Constraining the parameters for non-convective mixing on the red giant branch

@article{Abia2012CarbonAO,
  title={Carbon and oxygen isotopic ratios in Arcturus and Aldebaran - Constraining the parameters for non-convective mixing on the red giant branch},
  author={Carlos Abia and Sara Palmerini and Maurizio Busso and Sergio Cristallo},
  journal={Astronomy and Astrophysics},
  year={2012},
  volume={548}
}
Context. We re-analyzed the carbon and oxygen isotopic ratios in the atmospheres of the two bright K giants Arcturus (α Boo) and Aldebaran (α Tau). Aims. These stars are in the evolutionary stage following the first dredge-up (FDU). Previous determinations (dating back more than 20 years) of their 16 O/ 18 O ratios showed a rough agreement with FDU expectations; however, the estimated 16 O/ 17 Oa nd 12 C/ 13 Cr atios were lower than in the canonical predictions for red giants. Today these… 

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