The peculiar composition of the Sun is not related to giant planets

TL;DR

This study investigates the Sun's unique elemental composition by analyzing high-precision spectra of 50 stars, finding that its peculiarities are mainly due to Galactic chemical evolution rather than giant planets.

Contribution

It provides a detailed abundance analysis of stars with and without giant planets, highlighting the role of Galactic evolution over planetary influence in the Sun's composition.

Findings

The Sun is Li poor compared to similar stars.

Elemental abundance trends correlate with metallicity ([Fe/H]).

Differences in abundance gradients are linked to the presence of giant planets.

Abstract

Highly-differential spectroscopic studies have revealed that the Sun is deficient in refractory elements relative to solar twins. To investigate the role of giant planets on this signature, we present a high precision abundance analysis of HARPS spectra for 50 F- and G-type stars spanning -0.4<[Fe/H]<+0.5. There are 29 stars in the sample which host planets of masses > 0.01 MJup. We derive abundances for 19 elements, and apply corrections to 14 of them for systematic errors associated with one dimensional (1D) model atmospheres, or the assumption of local thermodynamic equilibrium (LTE), or both. We find that, among the solar twins in our sample, the Sun is Li poor in comparison to other stars at similar age, in agreement to previous studies. The sample shows a variety of trends in elemental abundances as a function of condensation temperature. We find a strong correlation in these trends with [Fe/H], with a marginally-significant difference in the gradients for stars with and without giants planets detected, that increases after applying 3D and non-LTE corrections. Our overall results suggests that the peculiar composition of the Sun is primarily related to Galactic chemical evolution rather than the presence of giant planets.