1995/05/08 by D. Kiselman, Dan Kiselman, Åke Nordlund +2
Chemistry · Earth and Planetary Sciences · Environmental Science · Physics and Astronomy · #Astrophysics (astro-ph) #Atmospheric Ozone and Climate #Atmospheric and Environmental Gas Dynamics #FOS: Physical sciences #Spectroscopy and Laser Applications #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/9505037
10 pages, uuencoded compressed PostScript file including figures, to appear in Astronomy & Astrophysics. Also available at ftp://www.astro.su.se/pub/dan
arxiv created 1995/05/08 · openalex publication_date 1995/05/08 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We study the formation of O I and OH spectral lines in three-dimensional hydrodynamic models of the solar photosphere. The line source function of the O I 777 nm triplet is allowed to depart from local thermodynamic equilibrium (LTE), within the two-level-atom approximation. Comparison with results from 1D models show that the 3D models alleviate, but do not remove, the discrepancy between the oxygen abundances reported from non-LTE work on the 777 nm triplet and from the [O I] 630 nm and OH lines. Results for the latter two could imply that the solar oxygen abundance is below 8.8 (lg(H) = 12). If this is confirmed, the discrepancy between theory and observation for the 777 nm triplet lines might fall within the range of errors in equivalent width measurements and f-values. The line source function of the 777 nm triplet in the 1.5D approximation is shown to differ insignificantly from the full 3D non-LTE result.