Parity-Nonconserving Nuclear Forces

Abstract

The effective single-particle weak parity-nonconserving potential is recalculated including parity-nonconserving one-pion exchange forces and the two-body correlations induced by the hard cores in the nucleon-nucleon potential. The circular polarization of the $\ensuremath{\gamma}$ ray from the 482-keV transition in $^{181}\mathrm{Ta}$ is calculated to be -(0.2\ifmmode\pm\else\textpm\fi{}0.1)\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}4}$. The measured value is -(0.06\ifmmode\pm\else\textpm\fi{}0.01)\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}4}$, showing that the observed parity nonconservation in nonleptonic $\ensuremath{\Delta}S=0$ transitions is in agreement with the Cabibbo theory of weak interactions.