The elemental composition of the Sun I. The intermediate mass elements Na to Ca

Understand

The composition of the Sun is an essential piece of reference data for astronomy, cosmology, astroparticle, space and geo-physics.

• This article, dealing with the intermediate-mass elements Na to Ca, is the first in a series describing the comprehensive re-determination of the solar composition.
• In this series we severely scrutinise all ingredients of the analysis across all elements, to obtain the most accurate, homogeneous and reliable results possible.
• We employ a highly realistic 3D hydrodynamic solar photospheric model, which has successfully passed an arsenal of observational diagnostics.