AGB stars of the intermediate-age LMC cluster NGC 1846 II. Dredge up along the AGB

  title={AGB stars of the intermediate-age LMC cluster NGC 1846 II. Dredge up along the AGB},
  author={Thomas Lebzelter and Michael T. Lederer and Sergio Cristallo and Kenneth H. Hinkle and Oscar Straniero and Bernhard Aringer},
  journal={Astronomy and Astrophysics},
Aims. We investigate the change in the surface abundance of 12 C during the evolution along the AGB, aiming to constrain third dredge-up models. Methods. High-resolution, near-infrared spectra of a sample of AGB stars in the LMC cluster NGC 1846 were obtained. A cluster sample ensures a high level of homogeneity with respect to age, metallicity, and distance. The C/O ratio and the ratio of 12 C/ 13 Cw ere measured and compared with our evolutionary models. Results. For the first time, we show… Expand
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