Related papers: A short look at epsilon'/epsilon
A brief review of CP violation in $K$ and $B$ decays is given. While the observables $\varepsilon$ and Re$(\varepsilon'/\varepsilon)$ describing CP violation in neutral $K$ decays do not allow a powerful test of the CKM mechanism of CP…
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. The 1/N_c…
The present theoretical status of the parameter for direct CP violation epsilon'/epsilon in the Standard Model is reviewed and compared with most recent experimental measurements of the same quantity. After collecting the basic expressions…
We calculate the CP-violating ratio epsilon'/epsilon in the Littlest Higgs model with T-parity (LHT) and investigate its correlations with the branching ratios for K_L -> pi^0 nu {bar nu}, K_L -> pi^0 l^+ l^- and K^+ -> pi^+ nu {bar nu}.…
In the QCD Sum Rule determination of $m_s$ using the two-point correlator of divergences of $\Delta S=1$ vector currents, the final uncertainty on $m_s$ is mainly due to the hadronic spectral function. Using a specific parameterization…
We calculate the new contribution to the direct CP-violation parameter $\epsilon'$ in $K\to \pi\pi$ decay in the minimal left-right symmetric model with the recently-obtained right-handed quark Cabibbo-Kobayashi-Maskawa mixing. We pay…
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…
I present three studies from the LHCb experiment on the subject of direct CP violation in $B^0$ and $B_s$ decays. First, we measure the CP asymmetry in $B^\pm\to\psi K^\pm$ decays, with $\psi=J/\psi, \psi(2S)$, using 0.35 $fb^{-1}$ of $pp$…
I discuss the comparison of the current theoretical calculations of epsilon'/epsilon with the experimental data. Lacking reliable ``first principle'' calculations, phenomenological approaches may help in understanding correlations among…
We point out that the observed CP violation in Bd - bar{Bd} mixing, taking into account the measured ratio Delta Md / Delta Ms, the recently improved lattice value of the non-perturbative parameter BK and an additional effective suppression…
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…
We present our preliminary results for the $\Delta I = 1/2$ matrix elements of $K\to\pi\pi$ decay and $\varepsilon'$, the measure of direct $CP$ violation in $K\to\pi\pi$, computed on multiple ensembles with periodic boundary conditions…
We have calculated the short distance QCD coefficient \eta_3 of the effective |\Delta S|=2-hamiltonian in the next-to-leading order. Since now all coefficients \eta_1, \eta_2 and \eta_3 are known beyond the leading log approximation, one…
Recent experimental improvements on K-decay data allow for a precise extraction of the strangeness-changing scalar K pi form factor and the related strange scalar spectral function. On the basis of this scalar as well as the corresponding…
The experimental value for the isospin amplitude Re(A_2) in K->pi pi decays has been successfully explained within the Standard Model, both within large N approach to QCD and by QCD lattice calculations. On the other hand in both approaches…
We present an exploratory calculation of the standard model Delta S=2 matrix element relevant for indirect CP violation in K -> pi pi decays. The computation is performed with overlap fermions in the quenched approximation at beta=6.0 on a…
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…
A left-right model with spontaneous $CP$ breakdown, consistent with the particle physics phenomenology, is presented. Constraints on free parameters of the model: mass of the new right handed gauge boson $M_2$ and ratio $r$ of the two…
I give a pedagogical introduction into flavour-changing neutral current interactions of kaons and their role to reveal or constrain physics beyond the Standard Model (SM). Then I discuss the measure $\epsilon_K^\prime$ of direct CP…
The status of heavy-quark decays as of summer 1999 is reviewed. New measurements of semileptonic B decays from LEP and from CLEO are reported and the status of determining the CKM parameters |Vcb| and |Vub| is assessed. Rare charmless…