ε'/ε and delta I=1/2 rule in nonlinear sigma model with scalar resonance

We discuss the hadronic matrix elements of the QCD and electroweak penguin operators in kaon decay, K → ππ, using nonlinear sigma model with scalar resonances. The scalar mesons are introduced as a nonet representation of flavor SU(3) transformation. The propagators of these scalar resonances have effect of resuming a certain class of chiral corrections to the matrix elements to all order in chiral perturbation theory. Using this model impact on the physical observable in kaon decay, ΔI=1/2 rule and ε'/ε, are discussed. We show the effects of σ meson are of great importance in kaon decay when mass of the σ meson is near to the kaon mass due to propagator enhancement. However results show that we are still missing some large amount of contributions to explain both of ΔI=1/2 rule and ε'/ε consistently. (author)