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Related papers: Update on $\varepsilon_K$ with lattice QCD inputs

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A brief review of lattice calculations of the bag parameter B_K relevant for understanding indirect CP violation in the neutral kaon sector is given. A status report on current state-of-the-art calculations is presented as well as a…

High Energy Physics - Lattice · Physics 2007-05-23 Rajan Gupta

A lattice QCD approach to the calculation of the long-distance contributions to $\epsilon_K$ is presented. This parameter describes indirect CP violation in $K\to\pi\pi$ decay. While the short-distance contribution to $\epsilon_K$ can be…

High Energy Physics - Lattice · Physics 2023-09-06 Ziyuan Bai , Norman H. Christ , Joseph M. Karpie , Christopher T. Sachrajda , Amarjit Soni , Bigeng Wang

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…

High Energy Physics - Lattice · Physics 2009-11-10 Junichi Noaki , RBC Collaboration

The first lattice result from the RBC and UKQCD Collaborations and improved perturbative calculations of $\varepsilon^{\prime}_K / \varepsilon_K$ have implied that the Standard-Model (SM) expectation deviates from measured values at the…

High Energy Physics - Phenomenology · Physics 2018-11-09 Teppei Kitahara

We show that it is now possible to fully determine the CKM matrix, for the first time, using lattice QCD. |V_{cd}|, |V_{cs}|, |V_{ub}|, |V_{cb}| and |V_{us}| are, respectively, directly determined with our lattice results for form factors…

High Energy Physics - Lattice · Physics 2007-05-23 Masataka Okamoto

The status of Lattice QCD is reviewed with respect to results that are relevant to Standard Model phenomenology. I argue that in a few simple cases all (or almost all) systematic errors from the lattice calculation are under control.…

High Energy Physics - Phenomenology · Physics 2008-02-03 Aida X. El-Khadra

The 2012 PDG reports a tension at the level of $3 \sigma$ between two exclusive determinations of $|V_{ub}|$. They are obtained by combining the experimental branching ratios of $B \to \tau \nu$ and $B \to \pi l \nu$ (respectively) with a…

High Energy Physics - Lattice · Physics 2012-11-28 F. Bahr , F. Bernardoni , B. Blossier , J. Bulava , M. Della Morte , P. Fritzsch , N. Garron , A. Gérardin , J. Heitger , G. von Hippel , A. Ramos , H. Simma , R. Sommer

The quantity $\varepsilon'/\varepsilon$ measures direct CP violation in Kaon decays. Recent SM predictions show a $2.9\sigma$ tension with data, with the theoretical uncertainty dominating. As rapid progress on the lattice is bringing…

High Energy Physics - Phenomenology · Physics 2017-04-05 M Cerdà-Sevilla , M Gorbahn , S Jäger , A Kokulu

We present results for the light quark masses and the neutral kaon mixing parameter $B_K$ from lattice QCD. Our data set includes lighter than physical light quark masses and 5 lattice spacings so that chiral extrapolation is not necessary…

High Energy Physics - Phenomenology · Physics 2012-07-02 Christian Hoelbling

We report the first lattice QCD calculation of the complex kaon decay amplitude $A_0$ with physical kinematics, using a $32^3\times 64$ lattice volume and a single lattice spacing $a$, with $1/a= 1.3784(68)$ GeV. We find Re$(A_0) =…

High Energy Physics - Lattice · Physics 2016-01-21 Z. Bai , T. Blum , P. A. Boyle , N. H. Christ , J. Frison , N. Garron , T. Izubuchi , C. Jung , C. Kelly , C. Lehner , R. D. Mawhinney , C. T. Sachrajda , A. Soni , D. Zhang

A recent Letter~\cite{Borsanyi:2025dyp} employs lattice QCD calculations of the equation of state, combined with entropy-density contour analysis, to place a lower bound of $\mu_B \gtrsim 450$~MeV on the location of the QCD critical…

High Energy Physics - Lattice · Physics 2026-04-01 Roy A. Lacey

The recent release of improved lattice data has revived again the interest on precise theoretical calculations of the direct CP-violation ratio $\varepsilon'/\varepsilon$. We present a complete update of the Standard Model prediction [1,2],…

High Energy Physics - Phenomenology · Physics 2019-12-03 V. Cirigliano , H. Gisbert , A. Pich , A. Rodríguez-Sánchez

The parameter epsilon_K, that quantifies CP violation in kaon mixing, is the observable setting the strongest constraints on new physics with a generic flavour and CP structure. While its experimental uncertainty is at the half percent…

High Energy Physics - Phenomenology · Physics 2016-06-03 Filippo Sala

We report the results of a calculation of the K --> pi pi matrix elements relevant for the $\DIhalf$ rule and $\epe$ in quenched lattice QCD using domain wall fermions at a fixed lattice spacing $a^{-1} \sim 2$ GeV. Working in the…

High Energy Physics - Lattice · Physics 2008-11-26 T. Blum , P. Chen , N. Christ , C. Cristian , C. Dawson , G. Fleming , R. Mawhinney , S. Ohta , G. Siegert , A. Soni , P. Vranas , M. Wingate , L. Wu , Y. Zhestkov , RBC Collaboration

We update our 1993 analysis of the CP violating ratio $\epe$ in view of the changes in several input parameters, in particular the improved value of the top quark mass. We also investigate the strange quark mass $m_s$ dependence of $\epe$…

High Energy Physics - Phenomenology · Physics 2014-11-17 A. J. Buras , M. Jamin , M. E. Lautenbacher

After a brief introduction to lattice QCD, I summarize the results for the light quark masses and the bag parameters $B_K$, $B_6^{1/2}$, and $B_8^{3/2}$. The implications of these results for the standard model estimates of CP violation…

High Energy Physics - Phenomenology · Physics 2007-05-23 Rajan Gupta

We present a calculation of the standard model \Delta S=2 matrix element relevant to indirect CP violation in K->\pi\pi decays which uses Neuberger's chiral formulation of lattice fermions. The computation is performed in the quenched…

High Energy Physics - Phenomenology · Physics 2009-11-10 Nicolas Garron , Leonardo Giusti , Christian Hoelbling , Laurent Lellouch , Claudio Rebbi

Significant progress has recently been achieved in the lattice gauge theory calculations required for extracting the fundamental parameters of the standard model from experiment. Recent lattice determinations of such quantities as the kaon…

High Energy Physics - Phenomenology · Physics 2015-06-25 Paul B. Mackenzie

The two most precise determinations of the CKM matrix element V_us are based on the analyses of leptonic and semileptonic kaon decays. These studies also rely on the lattice QCD calculations of two hadronic parameters, namely the ratio of…

High Energy Physics - Lattice · Physics 2013-09-11 Vittorio Lubicz

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…

High Energy Physics - Phenomenology · Physics 2014-11-17 S. Bertolini , J. O. Eeg , M. Fabbrichesi