The Sun. A typical star in the solar neighborhood?

TL;DR

This paper examines whether the Sun's chemical abundance pattern is typical of its neighborhood, considering high-precision differences and potential planet formation signatures.

Contribution

It provides a high-precision comparison of the Sun's chemical pattern with solar twins, exploring planet formation effects and neutron-capture element enhancements.

Findings

The Sun appears abnormal at high precision compared to solar twins.

Refractory element deficiency may relate to terrestrial planet formation.

Neutron-capture element enhancement observed in 18 Sco.

Abstract

The Sun is used as the fundamental standard in chemical abundance studies, thus it is important to know whether the solar abundance pattern is representative of the solar neighborhood. Albeit at low precision (0.05 - 0.10 dex) the Sun seems to be a typical solar-metallicity disk star, at high precision (0.01 dex) its abundance pattern seems abnormal when compared to solar twins. The Sun shows a deficiency of refractory elements that could be due to the formation of terrestrial planets. The formation of giant planets may also introduce a signature in the chemical composition of stars. We discuss both planet signatures and also the enhancement of neutron-capture elements in the solar twin 18 Sco.