The solar silicon abundance based on 3D non-LTE calculations

TL;DR

This study uses advanced 3D non-LTE radiative transfer calculations to determine the solar silicon abundance, finding a value of 7.51 dex that supports existing meteoritic abundance scales.

Contribution

It introduces comprehensive 3D non-LTE modeling with realistic hydrogen collision data to refine the solar silicon abundance measurement.

Findings

Non-LTE abundance correction is approximately -0.01 dex.

The derived solar silicon abundance is 7.51 dex.

Meteoritic abundance scale remains consistent with previous studies.

Abstract

We present three-dimensional (3D) non-local thermodynamic equilibrium (non-LTE) radiative transfer calculations for silicon in the solar photosphere, using an extensive model atom that includes recent, realistic neutral hydrogen collisional cross-sections. We find that photon losses in the SiI lines give rise to slightly negative non-LTE abundance corrections of the order -0.01 dex. We infer a 3D non-LTE based solar silicon abundance of 7.51 dex. With silicon commonly chosen to be the anchor between the photospheric and meteoritic abundances, we find that the meteoritic abundance scale remains unchanged compared with the Asplund et al. (2009) and Lodders et al. (2009) results.