Composition and thermodynamics of nuclear matter with light clusters

Abstract

We investigate nuclear matter at finite temperature and density, including the formation of light clusters up to the alpha particle. The novel feature of this work is to include the formation of clusters as well as their dissolution due to medium effects in a systematic way using two many-body theories: a microscopic quantum statistical (QS) approach and a generalized relativistic mean field (RMF) model. Nucleons and clusters are modified by medium effects. Both approaches reproduce the limiting cases of nuclear statistical equilibrium (NSE) at low densities and cluster-free nuclear matter at high densities. The treatment of the cluster dissociation is based on the Mott effect due to Pauli blocking, implemented in slightly different ways in the QS and the generalized RMF approaches. We compare the numerical results of these models for cluster abundances and thermodynamics in the region of medium excitation energies with temperatures T