THE INTEGRODIFFERENTIAL EQUATION APPROACH COMPARED WITH SHELL-MODEL CALCULATIONS ON THE HE-4 NUCLEUS

We show that for the He-4 ground state and effective potentials the integrodifferential equation approach (IDEA) produces binding energies which are more accurate than those calculated using a harmonic oscillator shell model basis and requires little numerical effort. This is because the IDEA employs the potential harmonic (PH) basis which is complete for two-body correlations generated by a two-body force, requiring only the solution of a two-variable integrodifferential equation of the Faddeev type. It can also easily be extended to larger nuclei with no additional effort and to realistic forces for He-4.