The chemical composition of a mild barium star HD202109

TL;DR

This study analyzes the chemical abundances of the mild barium star HD202109 using high-resolution spectroscopy, revealing new elemental overabundances and supporting the wind accretion model for its heavy element enrichment.

Contribution

It provides detailed elemental abundances for 51 elements in HD202109, including many not previously measured, and supports the wind accretion scenario for barium star enrichment.

Findings

Identified overabundances of 51 elements, including 27 previously unmeasured.

Confirmed that the heavy element overabundances align with the wind accretion model.

Provided atmospheric parameters and spectral analysis methods for the star.

Abstract

We present the result of chemical abundances of a mild barium star HD202109 (zeta Cyg) determined from the analysis of spectrum obtained by using a 2-m telescope at the Peak Terskol Observatory and a high-resolution spectrometer with R=80,000, signal to noise ratio >100. We also present the atmospheric parameters of the star determined by using various methods including iron-line abundance analysis. For line identifications, we use whole-range synthetic spectra computed by using the Kurucz database and the latest lists of spectral lines. Among the determined abundances of 51 elements, those of P, S, K, Cu, Zn, Ge, Rb, Sr, Nb, Mo, Ru, Rh, Pd, In, Sm, Gd, Tb, Dy, Er, Tm, Hf, Os, Ir, Pt, Tl, and Pb have not been previously known. Under the assumption that the overabundance pattern of Ba stars is due to wind-accretion process, adding information of more element abundances enables one to show that the heavy element overabundances of HD202109 can be explained with the wind accretion scenario model.