Abstract
Light clusters (mass number $A \leq 4$) in nuclear matter at subsaturation densities are described using a quantum statistical approach. In addition to self-energy and Pauli-blocking, effects of continuum correlations are taken into account to calculate the quasiparticle properties and abundances of light elements. Medium-modified quasiparticle properties are important ingredients to derive a nuclear matter equation of state applicable in the entire region of warm dense matter below saturation density [1]. An important application is the symmetry energy which is sensitive to few-body correlations at low densities [2,3]. In contrast to a mean-field approach neglecting cluster formation, the symmetry energy becomes strongly temperature dependent if few-nucleon correlations are taken into account. The properties of light clusters and continuum correlations in dense matter are of interest for nuclear structure calculations, heavy ion collisions, and for astrophysical applications such as the formation of neutron stars in core-collapse supernovae [4].

[1] G. Roepke, arXiv: 1411.4593;
[2] K. Hagel, J.B. Natowitz, and G. Roepke, Eur. Phys. J. A (2014) 50: 39;
[3] S. Typel, H. H. Wolter, G. Roepke, and D. Blaschke, Eur. Phys. J. A (2014) 50: 17;
[4] M. Hempel, K. Hagel, J. Natowitz, G. Roepke, and S. Typel, Phys.Rev. C 91, 045805 (2015).