An improvement of the recently developed effective interaction method for the hyperspherical formalism is presented. The method is extended to include contributions of three-body effective forces and of the nonadiabatic kinetic energy term. The role of these two additional contributions is tested on the binding energy of ${}^4\mathrm{He}$ and ${}^6\mathrm{Li}$ using semirealistic and more realistic NN potential models. The rate of convergence is improved considerably, opening up the possibility to use the method with realistic two- and three-body potentials for the $\alpha$-particle and for few-body nuclei with more than four nucleons.

• Received 31 January 2003

DOI:https://doi.org/10.1103/PhysRevC.67.054003