The Effective Mass Using Skyrme Interactions

The effective mass concept was introduced for small non-local potentials. For Skyrme interactions the effective mass depends on the density of the system. We parameterized the density by a generalised Fermi distribution. The parameters of the distribution are fitted with the charge root mean square radii of spherical nuclei. To test the parameters of the velocity dependent term of the interaction at high density or temperature, we studied the behaviour of the effective mass with density and temperature. The behaviour of the Landau parameter F1 was also discussed. We applied this study to most of the well known Skyrme forces. We recommended SKM* and SKS4 as good examples of Skyrme forces as they reveal small non-locality effects and well behaved functions at high density and temperature. (author)