Related papers: Towards NNLO accuracy for $\varepsilon'/\varepsilo…
We review the Standard Model predictions of CP violation in kaon decays. We present an elementary introduction to Chiral Perturbation Theory, four--quark effective hamiltonians and the relation among them. Particular attention is devoted to…
New physics contributions to the $Z$ penguin are revisited in the light of the recently-reported discrepancy of the direct CP violation in $K\to\pi\pi$. Interference effects between the standard model and new physics contributions to…
The amplitudes of $K \rightarrow \pi \gamma^* \rightarrow \pi e^+e^-$ and $K \rightarrow \pi \pi \gamma$ decays have been calculated within chiral Lagrangian approach including higher-order derivative terms and meson loops. The…
Recent progress in the determination of hadronic matrix elements has revealed a tension between the measured value of $\epsilon_K^{\prime}/\epsilon_K$, which quantifies direct $CP$ violation in $K \to \pi\pi$ decays, and the Standard-Model…
We report measurements of direct CP-violating asymmetries in charmless decays of neutral bottom hadrons to pairs of charged hadrons with the upgraded Collider Detector at the Fermilab Tevatron. Using a data sample corresponding to 1 fb-1 of…
We study the $K^0_S-K^0_L$ asymmetries and $CP$ violations in charm-baryon decays with neutral kaons in the final state. The $K^0_S-K^0_L$ asymmetry can be used to search for two-body doubly Cabibbo-suppressed amplitudes of charm-baryon…
We present a new analysis of the ratio epsilon'/epsilon which measures the direct CP violation in K\to\pi\pi decays. We use the 1/N_c expansion within the framework of the effective chiral lagrangian for pseudoscalar mesons. From general…
In this lecture I review the present status of CP violation in the Standard Model and some of its extensions and discuss ways to distinguish different models. Contents 1. Introduction 2. CP violation in the Standard Model 3. Test the…
We summarize both the study of CP violation with $K$ and $B$ mesons, as well as rare decays of kaons, emphasizing recent developments. The topics discussed include the unitarity triangle, $\epsilon'/\epsilon$, $K\to\pi\nu\bar\nu$ and other…
We investigate direct CP violation in neutral meson decays by reconstructing the associated density matrices and measuring their difference using the trace distance. Our results cover neutral kaon decays into two scalar triplets of isospin…
We present theoretical results for the indirect CP violation parameter, $ |\varepsilon_K| $, evaluated directly within the Standard Model using lattice QCD inputs including $ B_K $, $ |V_{cb}| $, $ |V_{us}| $, $ |V_{ud}| $, $ \xi_0 $, $…
We study the predictions for the direct CP violation parameter epsilon'/epsilon in a class of string-inspired model with non-universal soft A-terms. We show that the non-universality of the A-terms plays an important rule in enhancing the…
First preliminary measurement of the direct CP-violating parameter Ag by the NA48/2 experiment at CERN SPS is presented. Using more than 1.6 billions of charged kaon decays into three charged pions, the charge asymmetry in the…
I report some recent results on direct CP violation measurements in hadronic decays collected by the upgraded Collider Detector (CDF II) at the Fermilab Tevatron: CP-violating asymmetries in the two-body non-leptonic charmless decays of…
We briefly overview the historical controversy around Standard Model predictions of $\varepsilon'/\varepsilon$ and clarify the underlying physics. A full update of this important observable is presented, with all known short- and…
Using a left-right symmetric model with Spontaneous CP Violation and the hypothesis of a weakly first order electroweak phase transition we derive a relation between the produced baryon asymmetry and the observed parameter $\varepsilon$,…
A phenomenological paradigm for the study of CPT-violating effects in the neutral kaon system is presented. Besides the familiar direct and indirect breakings, it encodes possible phenomena leading to irreversibility and dissipation, that…
Three European experiments are engaged at present in the study of CP violation in the kaon system. In particular, NA48/1 and KLOE are concerned with the K-short decaying into three pions, while NA48/2 and KLOE study the charged kaon…
Using the recent first lattice results of the RBC-UKQCD collaboration for $K \to \pi\pi$ decays, we perform a phenomenological analysis of $\epsilon_K^{\prime}/\epsilon_K$ and find a discrepancy between SM prediction and experiments by…
We analyze various theoretical aspects of CP violation in singly Cabibbo suppressed (SCS) D-meson decays, such as $D \to K K,\pi \pi$. In particular, we explore the possibility that CP asymmetries will be measured close to the present level…