The Proton-Proton Interaction

Abstract

This paper presents a phenomenological analysis of the proton-proton scattering observed at 32 and 340 Mev in terms of static nuclear potentials. Comparison of these results with the neutron-proton scattering at 40, 90, and 280 Mev analyzed previously indicates that nuclear forces are not charge independent. In particular, there is definite evidence in the $n\ensuremath{-}p$ scattering data that but little scattering occurs in the odd parity states, whereas the high $p\ensuremath{-}p$ cross section apparently must be due to scattering in the (odd parity) triplet states. (This holds true even if velocity dependent spin orbit forces, i.e., $\ensuremath{\sigma}\ifmmode\cdot\else\textperiodcentered\fi{}\mathbf{L}$, are included.)It is possible that the radial dependences found necessary for $p\ensuremath{-}p$ scattering would be acceptable for the $n\ensuremath{-}p$ scattering even though the exchange behavior is different. A definite statement regarding this must await detailed calculations, however.Finally, we must take notice of the fact that no large repulsive forces have shown up in either the $n\ensuremath{-}p$ or the $p\ensuremath{-}p$ system of sufficient magnitude to account for nuclear saturation if saturation is to be predicted from two body forces. In both cases they would have been very easily detected, independent of the potential model assumed.