C, N and O abundances in red clump stars of the Milky Way

  title={C, N and O abundances in red clump stars of the Milky Way},
  author={Gra{\vz}ina Tautvai{\vs}ienė and Bengt Edvardsson and E. Puzeras and G. Barisevicius and Ilya Ilyin},
  journal={Monthly Notices of the Royal Astronomical Society},
The Hipparcos orbiting observatory has revealed a large number of helium-core-burning 'clump' stars in the Galactic field. These low-mass stars exhibit signatures of extra mixing processes that require modelling beyond the first dredge-up of standard models. The 12 C/ 13 C ratio is the most robust diagnostic of deep mixing because it is insensitive to the adopted stellar parameters. In this paper we present 12 C/ 13 C determinations in a sample of 34 Galactic clump stars as well as abundances… Expand

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