Cluster Variational Calculations of the Equation of State for Infinite Nuclear Matter

We report variational calculations of the equation of state (EOS) for neutron matter and symmetric nuclear at zero temperature. We assume the Jastrow-type wave functions with spin-isospin-dependent central, tensor and spin-orbit correlation functions. With the two-body cluster approximation, the energies per nucleon are expressed in the terms of the correlation functions. Since the obtained saturation point of symmetric nuclear matter is not in good agreement with the empirical one, additional three-body nuclear forces are necessary. In this study, therefore, we evaluate the three-body potential energies with the UrbanaIX potential, energies are determined so as to reproduce the empirical saturation point of symmetric nuclear matter. Finally, we extend the above calculations for asymmetric nuclear matter.