Another forbidden solar oxygen abundance: the [O I] 5577 Å line

Abstract

Context. Recent works with improved model atmospheres, line formation, atomic and molecular data, and detailed treatment of blends have resulted in a significant downward revision of the solar oxygen abundance. Aims. Considering the importance of the Sun as an astrophysical standard and the current conflict of standard solar models using the new solar abundances with helioseismological observations we have performed a new study of the solar oxygen abundance based on the forbidden [O i] line at 5577.34 A, not previously considered. Methods. High-resolution (R > 500 000), high signal-to-noise (S /N > 1000) solar spectra of the [O i] 5577.34 A line have been analyzed employing both three-dimensional (3D) and a variety of 1D (spatially and temporally averaged 3D, Holweger & Muller, MARCS and Kurucz models with and without convective overshooting) model atmospheres. Results. The oxygen abundance obtained from the [O i] 5577.3 A forbidden line is almost insensitive to the input model atmosphere