Line formation in solar granulation: III. The photospheric Si and meteoritic Fe abundances

TL;DR

This study uses advanced 3D hydrodynamical models to refine the solar photospheric silicon abundance, leading to adjustments in meteoritic element abundances and better agreement with recent measurements.

Contribution

It provides a more accurate determination of solar Si and Fe abundances using 3D models, improving upon previous 1D estimates and quantum broadening treatments.

Findings

Solar Si abundance is log Si = 7.51 ± 0.04.

Meteoritic Fe abundance is log Fe = 7.46 ± 0.01.

Adjusted abundances align better with recent photospheric measurements.

Abstract

Using realistic hydrodynamical simulations of the solar surface convection as 3D, time-dependent, inhomogeneous model atmospheres, the solar photospheric Si abundance has been determined to be log Si = 7.51 +- 0.04. This constitutes a difference of 0.04 dex compared with previous estimates based on the 1D Holweger-M\"uller (1974) model, of which half is attributable to the adopted model atmosphere and the remaining part to the improved quantum mechanical broadening treatment. As a consequence, all meteoritic abundances should be adjusted downwards by the same amount. In particular the meteoritic Fe abundance will be log Fe = 7.46 +- 0.01, in good agreement with the recently determined photospheric Fe abundance (Asplund et al. 2000b). The existing uncertainties unfortunately prevent an observational confirmation of the postulated effects of elemental migration of metals in the Sun.