Atomic diffusion and mixing in old stars

@article{Gavel2021AtomicDA,
  title={Atomic diffusion and mixing in old stars},
  author={Alvin Gavel and Pieter Gruyters and Ulrike Heiter and Andreas Korn and Thomas Nordlander and Kilian Hikaru Scheutwinkel and Olivier Richard},
  journal={Astronomy \& Astrophysics},
  year={2021}
}
Aims. We attempt to constrain the efficiency of additional transport or mixing processes that reduce the effect of atomic diffusion in stellar atmospheres. Methods. We apply spectral synthesis methods to spectra observed with the GIRAFFE spectrograph on the VLT to estimate abundances of Mg, Ti, Fe, and Ba in stars in the metal-poor globular cluster M 30. To the abundances we fit trends of abundances predicted by stellar evolution models assuming different efficiencies of additional transport or… 
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TLDR
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Abundances in a sample of turnoff and subgiant stars in NGC 6121 (M 4)
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