Pion Theory of Nuclear Forces

Recently a general and formal method to construct nuclear potentials has been proposed by Fukuda, Sawada and Taketani. Applying the method to the pion theory and adopting fixed and extended sources, we have evaluated nuclear potentials. The result seems to be in favour of that of Taketani, Machida and Onuma rather than that of Prueckner and Watson. As a cut-off function we assumed a Gaussian error function with k</it><inf>m</it>a</it>x</it></inf>=6µc</it>. In the case of the effective coupling constant g</it>2/4π=0.08 it is found that the effect of the extended source becomes very strong in the region for r</it>≪0.7 \hbar/µc</it>. If we use these potentials for r</it>>0.7 \hbar/µc</it> and phenomenological potentials inside this range, satisfactory results may be obtained to explain the properties of the two nucleon system in the low energy region.