Parity-violating $\pi NN$ coupling constant in the chiral quark-soliton model

Abstract

We investigate the parity-violating $\pi NN$ Yukawa coupling constant $h_{\pi NN}^1$ within the framework of the SU(2) chiral quark-soliton model, based on the $\Delta S=0$ effective weak Lagrangian derived within the same framework. We find that the parity-violating $\pi NN$ coupling constant is about $1\times 10^{-8}$ at the scale of 1 GeV. The results of $h_{\pi NN}^1$ turn out to be sensitive to the Wilson coefficient. We discuss how the gluonic renormalization supresses the parity-violating $\pi NN$ coupling constant.

Comments: 12 pages, 3 figures. Final version accepted for publication in Phys. Lett. B