Technetium and the third dredge up in AGB stars - I. Field stars

@article{Lebzelter2003TechnetiumAT,
  title={Technetium and the third dredge up in AGB stars - I. Field stars},
  author={Thomas Lebzelter and J. Hron},
  journal={Astronomy and Astrophysics},
  year={2003},
  volume={411},
  pages={533-542}
}
Context. Technetium (Tc) is an unstable element synthesised via the s-process in deep layers of asymptotic giant branch (AGB) stars, making it a reliable indicator of both recent s-process activity and third dredge-up. Aims. We searched for Tc in a sample of bright oxygen-rich asymptotic giant branch (AGB) stars located in the outer galactic bulge. We test theoretical predictions of the luminosity limit for the onset of third dredge-up. Methods. Using high-resolution optical spectra obtained… Expand

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