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Oxygen line formation in 3D hydrodynamical model atmospheres

M. Asplund
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Abstract

The formation of [O I], O I and OH lines in metal-poor stars has been studied by means of 3D hydrodynamical model atmospheres. For O I detailed 3D non-LTE calculations have been performed. While the influence of 3D model atmospheres is minor for [O I] and O I lines, the very low temperatures encountered at low metallicities have a drastic impact on the OH lines. As a result, the derived O abundances are found to be systematically overestimated in 1D analyses, casting doubts on the recent claims for a monotonic increase in [O/Fe] towards lower metallicities.

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M. Asplund. 2000-11-02. Oxygen line formation in 3D hydrodynamical model atmospheres. https://arxiv.org/abs/astro-ph/0011043

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