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Related papers: $\varepsilon'/\varepsilon$ in the Standard Model a…

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We present for the first time a master formula for $\varepsilon'/\varepsilon$, the ratio probing direct CP violation in $K \to \pi\pi$ decays, valid in any theory beyond the Standard Model (BSM). The formula makes use of hadronic matrix…

High Energy Physics - Phenomenology · Physics 2019-08-09 Jason Aebischer , Christoph Bobeth , Andrzej J. Buras , Jean-Marc Gérard , David M. Straub

We report recent progress on $\varepsilon_K$ evaluated directly from the standard model (SM) with lattice QCD inputs such as $\hat{B}_K$, $|V_{cb}|$, $|V_{us}|$, $|V_{ud}|$, $\xi_0$, $\xi_2$, $\xi_\text{LD}$, $f_K$, and $m_c$. We find that…

High Energy Physics - Lattice · Physics 2023-12-22 Seungyeob Jwa , Jeehun Kim , Sunghee Kim , Sunkyu Lee , Weonjong Lee , Jaehoon Leem , Jeonghwan Pak , Sungwoo Park

We present recent updates for $\varepsilon_K$ determined directly from the standard model (SM) with lattice QCD inputs such as $\hat{B}_K$, $|V_{cb}|$, $|V_{us}|$, $\xi_0$, $\xi_2$, $\xi_\text{LD}$, $f_K$, and $m_c$. We find that the…

High Energy Physics - Lattice · Physics 2023-02-07 Sunghee Kim , Sunkyu Lee , Weonjong Lee , Jaehoon Leem , Sungwoo Park

We analyze the CP violating ratio \epe=epsilon'/epsilon in the Standard Model in view of the new KTeV results. We review the present status of the most important non-perturbative parameters B_6, B_8, B_K and of the strange quark mass m_s.…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Bosch , A. J. Buras , M. Gorbahn , S. Jäger , M. Jamin , M. E. Lautenbacher , L. Silvestrini

We report recent progress on $\varepsilon_K$ evaluated directly from the standard model (SM) with lattice QCD inputs such as $\hat{B}_K$, exclusive $|V_{cb}|$, $|V_{us}|$, $|V_{ud}|$, $\xi_0$, $\xi_2$, $\xi_\text{LD}$, $f_K$, and $m_c$. We…

High Energy Physics - Lattice · Physics 2025-02-11 Seungyeob Jwa , Jeehun Kim , Sunghee Kim , Sunkyu Lee , Weonjong Lee , Jaehoon Leem , Sungwoo Park

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…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Bertolini

We analyze the theoretical implications of the new KTeV measurement of direct CP-violation in K->pi pi decays. The result is found consistent with the Standard Model for low values of the strange quark mass m_s. If the hadronic parameters…

High Energy Physics - Phenomenology · Physics 2014-11-17 Y. -Y. Keum , U. Nierste , A. I. Sanda

We present a new analysis of the ratio epsilon'/epsilon within the Standard Model (SM) using a formalism that is manifestly independent of the values of leading (V-A)x(V-A) QCD penguin, and EW penguin hadronic matrix elements of the…

High Energy Physics - Phenomenology · Physics 2016-01-27 Andrzej J. Buras , Martin Gorbahn , Sebastian Jäger , Matthias Jamin

I shortly review the present status of the theoretical calculations of epsilon'/epsilon and the comparison with the present experimental results. I discuss the role of higher order chiral corrections and in general of non-factorizable…

High Energy Physics - Phenomenology · Physics 2009-11-07 Stefano Bertolini

We discuss a new estimate of $\varepsilon '/\varepsilon$ in the kaon system. The present approach is based on the evaluation of the hadronic matrix elements of the \mbox{$\Delta S =1$} effective quark lagrangian by means of the chiral quark…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Bertolini

Using Chiral Perturbation Theory to properly account for the dynamics of nonleptonic $K\to 2\,\pi$ decays, we found the Standard Model prediction for the CP violating ratio $\mbox{Re}\left(\varepsilon'/\varepsilon\right)=\left(14\pm…

High Energy Physics - Phenomenology · Physics 2020-12-18 Hector Gisbert

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

The real part of epsilon'/epsilon measures direct CP violation in the decays of the neutral kaons in two pions. It is a fundamental quantity which has justly attracted a great deal of theoretical as well as experimental work. Its…

High Energy Physics - Phenomenology · Physics 2009-09-25 S. Bertolini , J. O. Eeg , M. Fabbrichesi

A comprehensive overview of kaon decays is presented. The Standard Model predictions are discussed in detail, covering both the underlying short-distance electroweak dynamics and the important interplay of QCD at long distances. Chiral…

High Energy Physics - Phenomenology · Physics 2015-05-30 V. Cirigliano , G. Ecker , H. Neufeld , A. Pich , J. Portoles

We present a brief review of recent attempts to construct effective theories to describe the breaking of the electroweak symmetry in extensions of the Standard Model with new strongly interacting dynamics around the TeV scale. Particular…

High Energy Physics - Phenomenology · Physics 2014-11-20 Gino Isidori

The striking success of the Standard Model in explaining precision data and, at the same time, its lack of explanations for various fundamental phenomena, such as dark matter or the baryon asymmetry of the universe, suggests new physics at…

High Energy Physics - Phenomenology · Physics 2025-04-23 Gino Isidori , Felix Wilsch , Daniel Wyler

I summarize the status of the $\Delta I=1/2$ rule in $K\to\pi\pi$ decays within an {\it analytic} approach based on the dual representation of QCD as a theory of weakly interacting mesons for large $N$, where $N$ is the number of colours.…

High Energy Physics - Phenomenology · Physics 2014-10-08 Andrzej J. Buras

The theoretical status of direct CP violation $\epsilon'/\epsilon$ is briefly reviewed. Special attention is paid to the recent new consistent predictions for both the ratio $\epsilon'/\epsilon$ and the $\Delta I = 1/2$ rule within the…

High Energy Physics - Phenomenology · Physics 2017-08-23 Yue-Liang Wu

Including the recent preliminary results of BaBar and BELLE experiments, we update the currently allowed intervals for various CKM parameters: $\bar\rho$, $\bar\eta$, $\sin2\beta$, $\sin2\alpha$, $\sin^2\gamma$. We also update the SM…

High Energy Physics - Phenomenology · Physics 2010-02-03 Sven Bergmann , Gilad Perez

As an important step towards a complete next-to-leading order (NLO) QCD analysis of the ratio $\varepsilon'/\varepsilon$ within the Standard Model Effective Field Theory (SMEFT), we present for the first time the NLO master formula for the…

High Energy Physics - Phenomenology · Physics 2022-01-05 Jason Aebischer , Christoph Bobeth , Andrzej J. Buras , Jacky Kumar