High-precision, charge-dependent Bonn nucleon-nucleon potential

Abstract

We present a charge-dependent one-boson-exchange nucleon-nucleon $(\mathrm{NN})$ potential that fits the world proton-proton data below 350 MeV available in the year 2000 with a ${\ensuremath{\chi}}^{2}$ per datum of 1.01 for 2932 data and the corresponding neutron-proton data with ${\ensuremath{\chi}}^{2}/\mathrm{datum}$ $=1.02$ for 3058 data. This reproduction of the $\mathrm{NN}$ data is more accurate than by any phase-shift analysis and any other $\mathrm{NN}$ potential. This is achieved by the introduction of two effective $\ensuremath{\sigma}$ mesons the parameters of which are partial-wave dependent. The charge dependence of the present potential (which we call ``CD-Bonn'') is based upon the predictions by the Bonn full model for charge symmetry and charge-independence breaking in all partial waves with $J<~4.$ The potential is represented in terms of the covariant Feynman amplitudes for one-boson exchange which are nonlocal. Therefore, the off-shell behavior of the CD-Bonn potential differs in a characteristic way from commonly used local potentials and leads to larger binding energies in nuclear few- and many-body systems, where underbinding is a persistent problem.