Abundance analysis of s-process enhanced barium stars

TL;DR

This study analyzes the chemical compositions of four s-process enhanced barium stars using high-resolution spectra to understand neutron-capture nucleosynthesis and their role in Galactic chemical evolution.

Contribution

It provides detailed elemental abundance measurements for neutron-capture elements in four chemically peculiar stars, expanding observational data for s-process enrichment.

Findings

HD 49641 and HD 58368 are strong barium stars with [Ba/Fe] > 1.16.

HD 119650 and HD 191010 are mild barium stars with [Ba/Fe] ~ 0.4.

Elemental abundance patterns are interpreted in the context of nucleosynthesis theories.

Abstract

Detailed chemical composition studies of stars with enhanced abundances of neutron-capture elements can provide observational constraints for neutron-capture nucleosynthesis studies and clues for understanding their contribution to the Galactic chemical enrichment. We present abundance results from high-resolution spectral analyses of a sample of four chemically peculiar stars characterized by s-process enhancement. High-Resolution spectra (R ~ 42000) of these objects spanning a wavelength range from 4000 to 6800 A, are taken from the ELODIE archive. We have estimated the stellar atmospheric parameters, the effective temperature T_eff, the surface gravity log g, and metallicity [Fe/H] from local thermodynamic equilibrium analysis using model atmospheres. We report estimates of elemental abundances for several neutron-capture elements, Sr, Y, Zr, Ba, La, Ce, Pr, Nd, Sm, Eu and Dy. While HD 49641 and HD 58368 show [Ba/Fe] > 1.16 the other two objects HD 119650 and HD 191010 are found to be mild barium stars with [Ba/Fe] ~ 0.4. The derived abundances of the elements are interpreted on the basis of existing theories for understanding their origin and evolution.