OCCASO III. Iron peak and $\alpha$ elements of 18 open clusters. Comparison with chemical evolution models and field stars

TL;DR

This paper provides a detailed chemical abundance analysis of 10 elements in 18 open clusters, comparing results with models and field stars to understand Galactic evolution and stellar nucleosynthesis.

Contribution

It offers a homogeneous, extensive dataset of open cluster abundances and compares these with models and field star data, enhancing understanding of Galactic chemical evolution.

Findings

Abundance trends vary with metallicity, radius, and age.

Radial migration influences chemical abundance patterns.

Clusters and field stars show distinct abundance behaviors.

Abstract

The study of open-cluster chemical abundances provides insights on stellar nucleosynthesis processes and on Galactic chemo-dynamical evolution. In this paper we present an extended abundance analysis of 10 species (Fe, Ni, Cr, V, Sc, Si, Ca, Ti, Mg, O) for red giant stars in 18 OCCASO clusters. This represents a homogeneous sample regarding the instrument features, method, line list and solar abundances from confirmed member stars. We perform an extensive comparison with previous results in the literature, and in particular with the Gaia FGK Benchmark stars Arcturus and $\mu$Leo. We investigate the dependence of [X/Fe] with metallicity, Galactocentric radius ($6.5<R_{\rm GC}<11$ kpc), age ($0.3<Age<10$ Gyr), and height above the plane ($|z|<1000$ pc). We discuss the observational results in the chemo-dynamical framework, and the radial migration impact when comparing with chemical evolution models. We also use APOGEE DR14 data to investigate the differences between the abundance trends in $R_{\rm GC}$ and $|z|$ obtained for clusters and for field stars.