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Related papers: Calculation of epsilon'/epsilon

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I review recent new lattice QCD results on a few selected topics which are relevant to the heavy ion physics community. Special emphasis is put on the QCD phase diagram towards the chiral limit and at nonzero baryon density as well as the…

High Energy Physics - Lattice · Physics 2021-02-03 Heng-Tong Ding

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…

High Energy Physics - Lattice · Physics 2025-01-31 Masaaki Tomii

Chiral effective field theory can provide valuable insight into the chiral physics of hadrons when used in conjunction with non-perturbative schemes such as lattice QCD. In this discourse, the attention is focused on extrapolating the mass…

High Energy Physics - Lattice · Physics 2015-03-17 J. M. M. Hall , F. X. Lee , D. B. Leinweber , K. F. Liu , N. Mathur , R. D. Young , J. B. Zhang

At the precision reached in current lattice QCD calculations, electromagnetic effects are becoming numerically relevant. Here, electromagnetic effects are included by superimposing $\mathrm{U}(1)$ degrees of freedom on $N_f = 2+1$ QCD…

Recently, we pointed out that chiral transformation properties of penguin operators change in the transition from unquenched to (partially) quenched QCD. As a consequence, new operators appear in (partially) quenched QCD penguins,…

High Energy Physics - Lattice · Physics 2009-11-07 Maarten Golterman , Elisabetta Pallante

We study the |Delta I|=3/2 amplitudes of the octet-hyperon decays B -> B' + pion and of the decays Omega^- -> Cascade + pion in the context of heavy-baryon chiral perturbation theory. For the octet-hyperon decays, we investigate the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Jusak Tandean

Firstly, we use the recent ALEPH/OPAL data on the V-A spectral functions for fixing the continuum threshold with which the first and second Weinberg sum rules should be satisfied in the chiral limit. Then, we predict the values of the…

High Energy Physics - Phenomenology · Physics 2009-09-25 Stephan Narison

In this paper we use one-loop chiral perturbation theory in order to compare lattice computations of the K+ to pi+ pi0 decay amplitude with the experimental value. This makes it possible to investigate three systematic effects that plague…

High Energy Physics - Lattice · Physics 2016-08-24 Maarten Golterman , Ka Chun Leung

We discuss a general strategy to compute the coefficients of QCD chiral Lagrangian by using the lattice regularization of QCD with Wilson fermions. This procedure requires the introduction of an effective Lagrangian for lattice QCD as an…

High Energy Physics - Lattice · Physics 2009-10-28 A. R. Levi , V. Lubicz , C. Rebbi

We study the impact of explicit chiral symmetry breaking of lattice Wilson fermions on mesonic correlators in the epsilon-regime using Wilson chiral perturbation theory. We generalize the epsilon-expansion of continuum chiral perturbation…

High Energy Physics - Lattice · Physics 2009-04-29 Oliver Bar , Silvia Necco , Stefan Schaefer

I review the current theoretical estimates of the CP-violating parameter eps'/eps, compare them to the experimental result and suggest a few guidelines in using the theoretical results.

High Energy Physics - Phenomenology · Physics 2009-10-31 Marco Fabbrichesi

The calculation of QCD corrections to the width difference Delta Gamma in the B_s meson system is presented. The next-to-leading order corrections reduce the dependence on the renormalization scale significantly and allow for a meaningful…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ulrich Nierste

A recently proposed strategy to quantify the role of the charm quark mass in the $\Delta I=1/2$ rule is reviewed. Results for the low-energy couplings of the $\Delta S=1$ chiral effective Hamiltonian in a theory with a light charm quark…

High Energy Physics - Lattice · Physics 2008-11-26 P. Hernandez

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…

High Energy Physics - Phenomenology · Physics 2014-07-10 Andrzej J. Buras , Fulvia De Fazio , Jennifer Girrbach

We compute the next-to-next-to-leading order (NNLO) QCD corrections to b \to c l \bar \nu_l decay rate at a fully differential level. Arbitrary cuts on kinematic variables of the decay products can be imposed. Our computation can be used to…

High Energy Physics - Phenomenology · Physics 2014-11-18 Kirill Melnikov

The direct CP violation parameter Re(epsilon'/epsilon) has been measured from the decay rates of neutral kaons into two pions using the NA48 detector at the CERN SPS. The 2001 running period was devoted to collecting additional data under…

High Energy Physics - Experiment · Physics 2008-11-26 J. R. Batley , NA48 collaboration

A recently proposed approach to compute the inclusive semi-leptonic decay rate on the lattice allows for the calculation of various quantities (differential distributions and moments) in different subchannels. We systematically compare the…

High Energy Physics - Phenomenology · Physics 2021-11-05 Paolo Gambino , Shoji Hashimoto , Sandro Mächler

We review some recent theoretical results on rare kaon decays. Particular attention is devoted to establish the short distance (direct CP violating) contribution to K_L => \pi^0 e \bar{e}. This is achieved by a careful study of the long…

High Energy Physics - Phenomenology · Physics 2007-05-23 Giancarlo D'Ambrosio

We investigate two-point correlation functions of left-handed currents computed in quenched lattice QCD with the Neuberger-Dirac operator. We consider two lattice spacings a~0.09,0.12 fm and two different lattice extents L~ 1.5, 2.0 fm;…

High Energy Physics - Lattice · Physics 2010-02-03 L. Giusti , P. Hernandez , S. Necco , C. Pena , J. Wennekers , H. Wittig

The phase diagram for the compact lattice QED with Wilson fermions is shown. We discuss different methods for the calculation of the 'pion' mass $m_{\pi}$ near the chiral transition point $\kappa_c(\beta )$.

High Energy Physics - Lattice · Physics 2009-10-28 A. Hoferichter , V. K. Mitrjushkin , M. Müller-Preussker