Gaia-ESO Survey. Trumpler 23

Atmospheric parameters were also used as a check on membership when available. Literature photometry was used to re-determine cluster parameters based on radial velocity member stars only; theoretical isochrones are fit in the V, V-I diagram. Cluster abundance measurements of ten radial-velocity member stars with high-resolution spectroscopy are presented for 24 elements.

These abundances have been compared to local disk stars, and where possible placed within the context of literature gradient studies. We find Trumpler 23 to have an age of 0.80+/-0.10Gyr, significant differential reddening with an estimated mean cluster E(V-I) of 1.02^+0.14^_-0.09_, and an apparent distance modulus of 14.15+/-0.20. We find an average cluster metallicity of [Fe/H]=0.14+/-0.03dex, a solar [{alpha}/Fe] abundance, and notably subsolar [s-process/Fe] abundances.