Abundance of zirconium in the atmospheres of red giants in Galactic globular cluster 47 Tuc

TL;DR

This study measures zirconium levels in 327 red giant stars within the globular cluster 47 Tuc, revealing an average abundance consistent with field stars and other clusters, using archival spectral data and synthetic modeling.

Contribution

It provides the first large-scale zirconium abundance analysis in 47 Tuc RGB stars using archival VLT spectra and synthetic spectral fitting.

Findings

Average [Zr/Fe] = +0.38 +/- 0.12 in 47 Tuc RGB stars

Zirconium abundance aligns with Galactic field stars and other globular clusters

Methodology utilizes archival spectra and synthetic spectral profiles

Abstract

We determined zirconium abundance in the atmospheres of 327 red giant branch (RGB) stars in the globular cluster 47 Tuc. The 1D LTE abundances were obtained from the archival VLT GIRAFFE spectra, using 1D hydrostatic ATLAS9 stellar model atmospheres and synthetic Zr I line profiles computed with the SYNTHE package. The average zirconium abundance determined in the sample of RGB stars, [Zr/Fe] = +0.38 +/- 0.12, agrees well with zirconium abundances obtained at this metallicity in the Galactic field stars, as well as with those observed in other Galactic globular clusters.