Related papers: The Delta I=1/2 rule and epsilon'/epsilon
The $\Delta I=1/2$ rule and direct CP violation $\epsilon'/\epsilon$ in kaon decays are studied within the framework of the effective Hamiltonian approach in conjunction with generalized factorization for hadronic matrix elements. We…
The low energy dynamics of QCD is investigated with special attention paid to the matching between QCD and chiral perturbation theory(ChPT), and also to some useful algebraic chiral operator relations which survive even when we include…
We have gained enough statistical precision to distinguish signal from noise in matrix elements of all operators relevant for the Delta I=1/2 rule in kaon decays and for the direct CP violation parameter epsilon-prime. We confirm…
I shortly review the present status of the theoretical calculations of epsilon'/epsilon and the comparison with the present experimental results. I discuss the role of higher order chiral corrections and in general of non-factorizable…
The $K\to\pi\pi$ decay amplitudes are studied within the framework of generalized factorization in which the effective Wilson coefficients are gauge-invariant, renormalization-scale and -scheme independent while factorization is applied to…
In this Ph.D. Thesis we analyze some CP-violating observables in Kaon decays. In Chapters 1-3 we describe the framework in which this Thesis has been developed and establish the definitions and notation. In Chapter 4 we study CP-violating…
I discuss the role of the Delta I = 1/2 selection rule in K -> pi pi decays for the theoretical calculations of eps'/eps. Lacking reliable ``first principle'' calculations, phenomenological approaches may help in understanding correlations…
I : Chiral Perturbation Theory is introduced and its applications to semileptonic and nonleptonic kaon decays are discussed. II: The method of large $N_c$ is used to calculate $K\to\pi\pi$ nonleptonic matrix elements, in particular the…
We discuss direct $CP$ violation in the standard model by giving a new estimate of $\varepsilon'/\varepsilon$ in kaon decays. Our analysis is based on the evaluation of the hadronic matrix elements of the \mbox{$\Delta S =1$} effective…
This thesis presents the setup and results of numerical calculation of hadronic matrix elements of Delta S=1 weak operators, with the aim of studying the Delta I=1/2 rule and direct CP violation. Such study provides a useful comparison of…
The measurement of epsilon'/epsilon has left open several theoretical problems, the most important of which is an accurate calculation of the relevant hadronic matrix elements. Here we study the possibility of relating epsilon' to CP…
I review a recent attempt to reproduce the isospin $I= 0$ and 2 amplitudes for the decay of a kaon into two pions by estimating the relevant hadronic matrix elements in the chiral quark model. The results are parametrized in terms of the…
We present a new analysis of the Delta I = 1/2 rule in K --> pi pi decays and the B_K parameter. We use the 1/N_c expansion within the effective chiral lagrangian for pseudoscalar mesons and compute the hadronic matrix elements at leading…
We give a progress report of our lattice calculation of direct and indirect CP violation in kaon decays, parametrized as $\epsilon'/\epsilon$ and $B_K$, which require non-perturbative calculation of the matrix elements of the Standard Model…
We calculate the hadronic matrix elements to $O(p^4)$ in the chiral expansion for the ($\Delta S =1$) $K^0 \to 2 \pi$ decays and the ($\Delta S=2$) $\bar K^0$-$K^0$ oscillation. This is done within the framework of the chiral quark model.…
The theoretical status of direct CP violation $\epsilon'/\epsilon$ is briefly reviewed. Special attention is paid to the recent new consistent predictions for both the ratio $\epsilon'/\epsilon$ and the $\Delta I = 1/2$ rule within the…
Violations of the $\Delta$I=1/2 rule are investigated in the nonmesonic weak hypernuclear decay using a weak $\Lambda$N$\to$NN transition potential based on meson exchange. While the weak $\Delta$I=3/2 matrix elements of baryons with…
The real part of epsilon'/epsilon measures direct CP violation in the decays of the neutral kaons in two pions. It is a fundamental quantity which has justly attracted a great deal of theoretical as well as experimental work. Its…
We compute the isospin $I= 0$ and 2 amplitudes for the decay of a kaon into two pions by estimating the relevant hadronic matrix elements in the chiral quark model. The results are parametrized in terms of the quark and gluon condensates…
I shortly review the present status of the theoretical estimates of eps'/eps. I consider a few aspects of the theoretical calculations which may be relevant in understanding the present experimental results. In particular, I discuss the…