The Galactic chemical evolution of oxygen inferred from 3D non-LTE spectral-line-formation calculations
Number of Authors: 4
2015 (English)In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 454, no 1, L11-L15 p.Article in journal (Refereed) Published
We revisit the Galactic chemical evolution of oxygen, addressing the systematic errors inherent in classical determinations of the oxygen abundance that arise from the use of one-dimensional (1D) hydrostatic model atmospheres and from the assumption of local thermodynamic equilibrium (LTE). We perform detailed 3D non-LTE radiative-transfer calculations for atomic oxygen lines across a grid of 3D hydrodynamic STAGGER model atmospheres for dwarfs and subgiants. We apply our grid of predicted line strengths of the [O I] 630 nm and O I 777 nm lines using accurate stellar parameters from the literature. We infer a steep decay in [O/Fe] for [Fe/H] greater than or similar to -1.0, a plateau [O/Fe] approximate to 0.5 down to [Fe/H] approximate to -2.5, and an increasing trend for [Fe/H] less than or similar to -2.5. Our 3D non-LTE calculations yield overall concordant results from the two oxygen abundance diagnostics.
Place, publisher, year, edition, pages
2015. Vol. 454, no 1, L11-L15 p.
line: formation, radiative transfer, methods: numerical, stars: abundances, stars: atmospheres, Galaxy: abundances
Astronomy, Astrophysics and Cosmology
IdentifiersURN: urn:nbn:se:su:diva-132627DOI: 10.1093/mnrasl/slv122ISI: 000378922200002OAI: oai:DiVA.org:su-132627DiVA: diva2:954623