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Related papers: Precision computation of the kaon bag parameter

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This report describes an observation of mixing-induced CP violation and a measurement of the CP violation parameter, sin(2phi_1), with the Belle detector at the KEKB asymmetric e+e- collider. Using a data sample of 29.1 fb-1 recorded on the…

High Energy Physics - Experiment · Physics 2008-11-26 Belle Collaboration , K. Abe

We compute the hadronic matrix elements of the four-quark operators relevant for $K^0-{\bar K^0}$ mixing beyond the Standard Model. Our results are from lattice QCD simulations with $n_f=2+1$ flavours of domain-wall fermion, which exhibit…

High Energy Physics - Lattice · Physics 2016-11-08 Nicolas Garron , Renwick J. Hudspith , Andrew T. Lytle

Neutral $B$ meson mixing matrix elements and $B$ meson decay constants are calculated. Static approximation is used for $b$ quark and domain-wall fermion formalism is employed for light quarks. The calculations are carried out on $2+1$…

High Energy Physics - Lattice · Physics 2015-06-30 Yasumichi Aoki , Tomomi Ishikawa , Taku Izubuchi , Christoph Lehner , Amarjit Soni

We present an unquenched $N_f=2$ lattice computation of the $B_{K}$ parameter which controls $K^0-\bar K^0$ oscillations. A partially quenched setup is employed with two maximally twisted dynamical (sea) light Wilson quarks, and valence…

We present the first unquenched, continuum limit, lattice QCD results for the matrix elements of the operators describing neutral kaon oscillations in extensions of the Standard Model. Owing to the accuracy of our calculation on \Delta S=2…

We present results for the \Delta S=2 matrix elements which are required to study neutral kaon mixing in the standard model (SM) and beyond (BSM). We also provide leading chiral order results for the matrix elements of the electroweak…

High Energy Physics - Lattice · Physics 2009-11-11 Ronald Babich , Nicolas Garron , Christian Hoelbling , Joseph Howard , Laurent Lellouch , Claudio Rebbi

I review recent lattice results in kaon physics, particularly in the determination of V_{us} and the B_K parameter of K^0-\bar{K}^0 mixing. I use lattice data to argue for the need of developing SU(2)_L \times SU(2)_R chiral perturbation…

High Energy Physics - Lattice · Physics 2014-11-20 C T Sachrajda

We discuss the status of the RBC & UKQCD collaboration's lattice determination of $\epsilon'$, the measure of direct CP-violation in kaon decays, focusing in particular on recent developments in statistical techniques for estimating…

High Energy Physics - Lattice · Physics 2019-11-13 Christopher Kelly , Tianle Wang

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…

High Energy Physics - Phenomenology · Physics 2017-06-21 Ulrich Nierste

Kaon flavour physics has played in the 1960s and 1970s a very important role in the construction of the Standard Model (SM) and in the 1980s and 1990s in SM tests with the help of CP violation in $K_L\to\pi\pi$ decays represented by…

High Energy Physics - Phenomenology · Physics 2018-08-01 Andrzej J. Buras

We report a first, complete lattice QCD calculation of the long-distance contribution to the $K^+\to\pi^+\nu\bar{\nu}$ decay within the standard model. This is a second-order weak process involving two four-Fermi operators that is highly…

High Energy Physics - Lattice · Physics 2017-06-28 Ziyuan Bai , Norman H. Christ , Xu Feng , Andrew Lawson , Antonin Portelli , Christopher T. Sachrajda

We present our results of lattice calculations of $B$ parameters, which parameterize $\Delta B$=2 transition amplitudes together with the leptonic decay constant. Calculations are made in the quenched approximation at $\beta$=5.7, 5.9, 6.0…

We report a direct lattice calculation of the $K$ to $\pi\pi$ decay matrix elements for both the $\Delta I=1/2$ and 3/2 amplitudes $A_0$ and $A_2$ on 2+1 flavor, domain wall fermion, $16^3\times32\times16$ lattices. This is a complete…

High Energy Physics - Lattice · Physics 2011-12-23 T. Blum , P. A. Boyle , N. H. Christ , N. Garron , E. Goode , T. Izubuchi , C. Lehner , Q. Liu , R. D. Mawhinney , C. T. Sachrajda , A. Soni , C. Sturm , H. Yin , R. Zhou

A self-consistent analysis of K --> 2pi and K --> 3pi decays within a unique framework of chiral dynamics applied to the QCD-corrected weak nonleptonic quark lagrangian has been performed. The results on K --> 2pi amplitudes at O(p^6),…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. A. Belkov , G. Bohm , A. V. Lanyov

A self-consistent analysis of K->2pi and K->3pi decays within a unique framework of chiral dynamics applied to the QCD-corrected weak nonleptonic quark lagrangian has been performed. The results on K->2pi amplitudes at O(p^6), including the…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. A. Bel'kov , G. Bohm , A. V. Lanyov , A. A. Moshkin

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

Motivated by recent indications that the rates of colour-allowed non-leptonic channels are not in agreement with their Standard Model expectations based on QCD factorisation, we investigate the potential to study CP asymmetries with these…

High Energy Physics - Phenomenology · Physics 2022-06-29 Tim Gershon , Alexander Lenz , Aleksey V. Rusov , Nicola Skidmore

With increasing requirements for greater precision, it becomes essential to describe the effects of isospin breaking induced by both quark masses and electro-magnetic effects. In this work we perform a lattice analysis of the weak decay…

High Energy Physics - Lattice · Physics 2023-09-18 Z. R. Kordov , R. Horsley , W. Kamleh , Y. Nakamura , H. Perlt , P. E. L. Rakow , G. Schierholz , H. Stüben , R. D. Young , J. M. Zanotti

After an introduction to the Standard-Model description of CP violation and a brief look at the present status of this phenomenon in the kaon system, a classification of non-leptonic B-decays is given and the formalism of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Robert Fleischer

We present a calculation of the kaon $B$-parameter, $B_K$, using lattice QCD. We use improved staggered valence and sea fermions, the latter generated by the MILC collaboration with $N_f=2+1$ light flavors. To control discretization errors,…