Light clusters in nuclear matter and the “pasta” phase

The effects of including light clusters in nuclear matter at low densities are investigated within four different parametrizations of relativistic models at finite temperature. Both homogeneous and inhomogeneous matter (pasta phase) are described for neutral nuclear matter with fixed proton fractions. We discuss the effect of the density dependence of the symmetry energy, the temperature, and the proton fraction on the nonhomogeneous matter forming the inner crust of protoneutron stars. It is shown that the number of nucleons in the clusters, the cluster proton fraction, and the sizes of the Wigner-Seitz cell and of the cluster are very sensitive to the density dependence of the symmetry energy.