Chemical abundances in metal-poor giants: limitations imposed by the use of classical 1D stellar atmosphere models

  title={Chemical abundances in metal-poor giants: limitations imposed by the use of classical 1D stellar atmosphere models},
  author={V. Dobrovolskas and A. Kuvcinskas and Hans-G. Ludwig and Elisabetta Caffau and Jonas Klevas and D. Prakapavivcius},
  journal={arXiv: Solar and Stellar Astrophysics},
In this work we have used 3D hydrodynamical (CO5BOLD) and 1D hydrostatic (LHD) stellar atmosphere models to study the importance of convection and horizontal temperature inhomogeneities in stellar abundance work related to late-type giants. We have found that for a number of key elements, such as Na, Mg, Si, Ca, Ti, Fe, Ni, Zn, Ba, Eu, differences in abundances predicted by 3D and 1D models are typically minor (< 0.1 dex) at solar metallicity. However, at [M/H] = -3 they become larger and reach… 

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