Thre-body forces in nuclear matter: a comparative analysis

Recently it has been found that Argonne v18 plus UIX fails to explain the measured neutron-deuteron doublet scattering length. By using an effective density dependent interaction derived from the UIX potential in Monte Carlo calculations, we have found that the underbinding of symmetric nuclear matter need not be ascribed to deficiencies in the variational wave function. These problems may be largely due to uncertainties associated with the description of three-nucleon inDteractions. A new generation of local three-body potentials providing an excellent descriptions of the properties of light nuclei, as well as of the neutron-deuteron doublet scattering length, has recently been derived. We have performed a comparative analysis of the equations of state of both pure neutron matter and symmetric nuclear matter obtained using these models of three-nucleon forces. None of these potentials simultaneously explains the emperical equilibroium density and binding energy of symmetric nuclear matter. However, two of them provide reasonable values of the saturation density. The ambiguity in the trearment of the contact term of the chiral inspired potentials is discussed.