Cluster correlations in dense matter and equation of state

Correlations in strongly interacting matter at subsaturation densities lead to the formation of clusters and the appearance of phases transitions with a change of thermodynamic properties and chemical composition. These features can be described in a generalized relativistic density functional approach using clusters as explicit degrees of freedom with medium-dependent properties. The model is constructed in order to provide equations of state for astrophysical applications. It can be adapted also to nuclear structure calculations with cluster correlations on the surface of heavy nuclei. The appearance of alpha-particles modifies the neutron skin thickness of neutron-rich nuclei and affects the correlation with the density dependence of the symmetry energy.