Stellar Parameters and Chemical Abundances of G Giants

TL;DR

This study provides detailed stellar parameters and chemical abundances for 99 G giant stars, aiding understanding of their composition, origins, and potential for hosting exoplanets, based on high-resolution spectra from Subaru Telescope.

Contribution

It offers the first comprehensive chemical abundance analysis of G giants in a Doppler survey, including 15 elements, and assesses their kinematic properties.

Findings

Most stars belong to the thin disk.

Stars show a range of metallicities from -0.8 to +0.2.

Chemical abundances vary with stellar properties.

Abstract

We present basic stellar parameters of 99 late-type G giants based on high resolution spectra obtained by the High Dispersion Spectrograph attached to Subaru Telescope. These stars are targets of a Doppler survey program searching for extra-solar planets among evolved stars, with a metallicity of -0.8<[Fe/H]<+0.2. We also derived their abundances of 15 chemical elements, including four $\alpha$-elements (Mg, Si, Ca, Ti), three odd-Z light elements (Al, K, Sc), four iron peak elements (V, Cr, Fe, Ni), and four neutron-capture elements (Y, Ba, La, Eu). Kinematic properties reveal that most of the program stars belong to the thin disk.