Oxygen line formation in 3D hydrodynamical model atmospheres
نویسنده
چکیده
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 OH. 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. 1
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تاریخ انتشار 2000