Summary
The amount of silicon in the solar photosphere is an important astrophysical quantity for connecting meteoritic abundances, solar neutrino fluxes and solar sound speed profiles. Determining an abundance depends on the choice of model atmosphere, spectral synthesis code and the choice of spectral lines. We find that high resolution 3D model atmospheres can lead to lines synthesised broader than observations, but including magnetic field effects can reverse this offset, since magnetic fields constrain the velocity fields to reduce turbulence.
Though recent works have reported successively lower values of the solar silicon abundance, we find an increase. This result suggests that the solar silicon abundance is not on as firm ground as previously believed, and perhaps points towards the necessity of using a combination of elements for determining meteoritic abundances on the solar scale. The investigation continues!
Published in Astronomy & Astrophysics Volume 668, A48. Siddhant A. Deshmukh, Hans-Guenter Ludwig, Arunas Kučinskas, Matthias Steffen, Paul S. Barklem, Elisabetta Caffau, Vidas Dobrovolskas, and Piercarlo Bonifacio (Dec. 2022). The Solar Photospheric Silicon Abundance According to CO5BOLD - Investigating Line Broadening, Magnetic Fields, and Model Effects