Gaia-ESO HR15N Ba and Eu abundances

The model infers Teff, logg, [Fe/H], vsini, A(Ba), and A(Eu); its reliability was quantified through multi-dimensional quality flags for the labels and detection strength of the Ba and Eu features. The uncertainties in the inferred stellar labels were obtained by combining the model's internal label-covariance errors with signal-to-noise-dependent dispersions. Our final catalogue contains stellar parameters for 36263 spectra, with ~21000 and ~400 reliable Ba and Eu abundances, respectively, satisfying multiple flagging criteria.

We obtained median uncertainties of ~38K in Teff, ~0.08dex in logg, ~0.04dex in [Fe/H], ~0.06dex in A(Ba), and ~0.02dex in A(Eu). External validation against the Gaia Benchmark Stars, GALAH DR4, and multiple open clusters shows good agreement across independent reference datasets. This study provides a comprehensive dataset of neutron-capture abundances in the Galactic disc observed with the Gaia-ESO HR15N set-up.

The resulting catalogue includes newly determined Ba and Eu abundances that complement those available from previous analyses, thereby enabling well-characterised investigations of neutron-capture enrichment patterns in open clusters. The model framework can readily be adapted to upcoming wide-field spectroscopic surveys such as 4MOST, WEAVE, and WST.