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Related papers: $\varepsilon'/\varepsilon$ in and beyond the Stand…

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We consider effects of CP violating phases in \mu and A_t parameters in the effective supersymmetric standard model on B\to X_s l^+ l^- and \epsilon_K. Scanning over the MSSM parameter space with experimental constraints including edm…

High Energy Physics - Phenomenology · Physics 2009-10-31 Seungwon Baek , Pyungwon Ko

We reappraise the question whether the Standard Model, and Minimal Flavor Violating (MFV) models at large, can simultaneously describe the observed CP violation in the K- and Bd-systems. We find that CP violation in the Bd-system, measured…

High Energy Physics - Phenomenology · Physics 2009-11-13 Andrzej J. Buras , Diego Guadagnoli

The recently observed direct CP violation in $B_d \to K^+ \pi^-$ has raised suggestions of possible new physics. A robust test of the standard model vs. new physics is its prediction of equal direct CP violation in $B_s \to K^- \pi^+$…

High Energy Physics - Phenomenology · Physics 2010-04-05 Harry J. Lipkin

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

We investigate CP-violation effects in the bosonic sector of the Standard Model (SM) with two Higgs doublets. First we calculate the mass eigenstates of the physical neutral Higgses for small but nonzero CP-violation parameter $\xi_{\ast}$,…

High Energy Physics - Phenomenology · Physics 2010-11-01 G. Cvetic

The study of $CP$ violation in hyperon transitions has a long history. In the early 2000s the HyperCP experiment made a major effort to seek $CP$-odd signals in the decay sequence $\Xi^-\to\Lambda \pi^-$ and $\Lambda\to p\pi^-$, which…

High Energy Physics - Phenomenology · Physics 2026-01-07 Xiao-Gang He , Xiao-Dong Ma , Jusak Tandean , German Valencia

The Positronium (Ps) system, a bound state of an electron and a positron, is suitable for testing the predictions of quantum electrodynamics (QED), since its properties can be perturbatively calculated to high accuracy and, unlike the…

Nuclear Experiment · Physics 2021-12-21 Elena Perez del Rio

We estimate B(K -> pi nu nubar) in the context of the Standard Model by fitting for lambda_t = Vtd x V*ts of the `kaon unitarity triangle' relation. We fit data from epsilon_K, the CP-violating parameter describing K-mixing, and a_{psi K},…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. H. Kettell , L. G. Landsberg , H. Nguyen

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. From general…

High Energy Physics - Phenomenology · Physics 2007-05-23 T. Hambye , P. H. Soldan

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

We study the corrections to $\epsilon^\prime /\epsilon$ in the minimal supersymmetric model at the leading order in QCD and QED. Supersymmetry can increase the standard model prediction for $\epsilon^\prime /\epsilon$ by at most 40\% for…

High Energy Physics - Lattice · Physics 2010-11-01 E. Gabrielli , G. F. Giudice

We present here the CP asymmetries in the decay rate and angular distributions of $\tau\to K_S\pi\nu_\tau$ decays in the Standard Model (SM) and beyond (BSM). The CP asymmetries in the SM are induced by the CP violation in $K^0-\bar{K}^0$…

High Energy Physics - Phenomenology · Physics 2024-07-08 Feng-Zhi Chen , Xin-Qiang Li

There is no doubt that in the coming years we will witness the renaissance of kaon flavour physics with crucial measurements of the branching ratios for the rare decays $K^+\rightarrow\pi^+\nu\bar\nu$ and $K_{L}\rightarrow\pi^0\nu\bar\nu$…

High Energy Physics - Phenomenology · Physics 2016-07-18 Andrzej J. Buras

Possible CP violation in supersymmetric (SUSY) extensions of the Standard Model (SM) is discussed. The consequences of CP violating phases in the gaugino masses, trilinear soft supersymmetry-breaking terms and the `mu' parameter are…

High Energy Physics - Phenomenology · Physics 2009-10-31 I. Hinchliffe , N. Kersting

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 investigate the possible sizes of all the CP-violating asymmetries offered by the angular distribution of rare decay $\Lambda_b\rightarrow \Lambda(\to p \pi^-) \ell^+\ell^-$ in the Standard Model and new physics scenarios motivated by…

High Energy Physics - Phenomenology · Physics 2023-07-21 Diganta Das , Jaydeb Das , Girish Kumar , Niladribihari Sahoo

In this work we study the CP violation for $\bar{B^0}\to J/\psi K_s$ and $\bar{B^0}\to \phi K_s$ up to leading and next-to-leading order QCD corrections in the standard model, two-Higgs-doublet model and the minimal supersymmetric extension…

High Energy Physics - Phenomenology · Physics 2009-10-30 Dong-Sheng Du , Mao-Zhi Yang

New sources of CP violation, beyond the known sources in the standard model (SM), are required to explain the baryon asymmetry of the universe. Measurement of a non-zero permanent electric dipole moment (EDM) for fundamental particles, such…

Nuclear Experiment · Physics 2021-05-05 Prajwal Mohanmurthy , Jeff A. Winger

We analyse for the first time the CP violating ratio $\varepsilon'/\varepsilon$ in $K\to \pi\pi$ decays in leptoquark (LQ) models. Assuming a mass gap to the electroweak (EW) scale, the main mechanism for LQs to contribute to…

High Energy Physics - Phenomenology · Physics 2021-01-19 Christoph Bobeth , Andrzej J. Buras

We describe CP violating observables in resonant $W^\pm$ and $W^\pm$ plus one jet production at the Tevatron. We present simple examples of CP violating effective operators, consistent with the symmetries of the Standard Model, which would…

High Energy Physics - Phenomenology · Physics 2010-11-01 S. Dawson , G. Valencia