On Puppi's Determination of the Pion-Nucleon Coupling Constant

Abstract

Recently, Puppi and Stanghellini investiguted the coupling constant in pion-nucleon interactions. It was found that there is a large difference between the coupling constants which can not be explained through the violation of charge symmetry which comes from electromagnetic effects. If Puppi's results were correct, not only the charge symmetry but also the locality of the interaction Hamiltonian would be-violated. The determination of the coupling constant can also be made by analyzing low-energy experimental data in the twonucleon system. The data from the two-nucleon system may be used to check Puppi's curious result. It cannot be concluded that his result is inconsistent with experimental data on nuclear forces when the experimental error is taken into account. More accurate experiments on n-p scattering and cautious analyses of them are highly desirable.