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Appendix E: Supplementary plots: line profile fitting results for 1D model atmospheres

In this appendix, we show the observed center-to limb variation of the line profiles of the O i IR triplet, separately for each component, in comparison with the best-fit theoretical non-LTE line profiles derived from various 1D model atmospheres. The best-fit values of the oxygen abundance, A(O), are given in the legend of each plot, as well as in Table 1 (together with the best-fit S_H values). The best fit correspond to the global minimum of χ² as defined by Eq. (4), i.e., simultaneously fitting the line profiles at all μ-angles. The quality of the fit can be judged from the reduced χ² values provided in the Table, as well as from the plots of the intensity difference I^obs−I^calc displayed below the plot of the line profiles.

	Fig. E.1 Same as in Fig. 3, except for the averaged 3D model atmosphere with ξmic = 1.0 km s-1.
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	Fig. E.2 Same as in Fig. 3, except for the Holweger-Müller model atmosphere with ξmic = 1.2 km s-1.
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	Fig. E.3 Same as in Fig. 3, except for the LHD model atmosphere with αMLT = 1.0 and ξmic = 1.2 km s-1.
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Appendix F: Supplementary plots: equivalent width fitting results

In this appendix, we show the center-to-limb variation of the observed equivalent widths, separately for each component of the O i IR triplet, in comparison with the theoretical results derived from various 1D model atmospheres. For given S_H = 0 and 8/3, the oxygen abundance is computed as the A(O) value that minimizes the global χ² given by Eq. (5). The best fit is defined as the

S_H – A(O) combination that corresponds to the global minimum of χ². The best-fit values of S_H and A(O) are given in Table 3. The quality of the fit can be judged from the reduced χ² values provided in the Table, as well as from the plots of the abundance difference shown in the bottom panels of each Figure. Here A(μ) is the value of A(O) obtained from fitting the line profile separately at the individual μ-angle, while denotes the A(O) value derived from simultaneously fitting the line profiles at all μ-angles.

	Fig. F.1 Same as in Fig. 7, except for the averaged 3D model atmosphere with ξmic = 1.0 km s-1. Best-fit solutions are not shown here, since they would require negative SH.
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	Fig. F.2 Same as in Fig. 7, except for the Holweger-Müller model atmosphere with ξmic = 1.2 km s-1.
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	Fig. F.3 Same as in Fig. 7, except for the LHD model atmosphere with αMLT = 1.0 and ξmic = 1.2 km s-1. Best-fit solutions are not shown here, since they would require negative SH.
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© ESO, 2015