Lithium depletion in solar analogs: age and mass effects

TL;DR

This study investigates how lithium abundance in Sun-like stars correlates with age, mass, and planetary presence, revealing significant links and supporting models with extra transport mechanisms.

Contribution

It provides new high-resolution spectroscopic measurements and confirms the strong age-Li correlation, also highlighting the impact of planetary presence on Li depletion.

Findings

Li abundance strongly correlates with stellar age.

Presence of planets is linked to lower Li abundances.

Results support models with additional transport mechanisms.

Abstract

The main goal of this work is to evaluate the correlation between Li abundance, age, and mass. Using high-quality ESO/HARPS data (R $\simeq$ 115 000; 270 $\leq$ SNR $\leq$ 1000), we measured Li abundances via spectral synthesis of the 6707.8 \r{A} $^7$Li line in 74 solar twins and analogs. Our joint analysis of 151 Sun-like stars (72 from our sample plus 79 solar twins from a previous study) confirms the strong Li abundance-age correlation reported by other works. Mass and convective envelope size also seem to be connected with Li abundance but with lower significance. We have found a link between the presence of planets and low Li abundances in a sample of 192 stars with a high significance. Our results agree qualitatively with non-standard models, and indicate that several extra transport mechanisms must be taken into account to explain the behaviour of Li abundance for stars with different masses and ages.