The Solar Oxygen Abundance Determined from Polarimetric Observations

Norton, Aimee A.; Socas-Navarro, H.
Bibliographical reference

American Astronomical Society Meeting 210, #25.02; Bulletin of the American Astronomical Society, Vol. 39, p.131

Advertised on:
5
2007
Number of authors
2
IAC number of authors
0
Citations
0
Refereed citations
0
Description
In this work we present support for recent claims that advocate a downward revision of the solar oxygen abundance. Our analysis employs spatially-resolved spectro-polarimetric observations including the Fe I lines at 6302 Angstroms, and the O I infrared triplet around 7774 Angstroms, in the quiet Sun. We used the Fe I lines to reconstruct the three-dimensional thermal and magnetic structure of the atmosphere. The simultaneous O I observations were then employed to determine the abundance of oxygen at each pixel, using both LTE and non-LTE (NLTE) approaches to the radiative transfer. In this manner, we obtain values of log eo=8.64 (NLTE) and 8.94 (LTE) dex. We find an unsettling fluctuation of the oxygen abundance over the field of view. This is likely an artifact indicating that, even with this relatively refined strategy, important physical ingredients are still missing in the picture. By examining the spatial distribution of the abundance, we estimate realistic confidence limits of approximately 0.1 dex.