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Related papers: Electromagnetic penguin operators and direct CP vi…

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The CP-violating charge asymmetry in decays K+- --> \pi+- \gamma\gamma, which is induced by the electromagnetic penguin operators, has been studied both in thestandard model and in its extensions. Because of a large enhancement of the…

High Energy Physics - Phenomenology · Physics 2009-11-07 Dao-Neng Gao

We consider the chargino contribution to the CP violation in $B \to \phi K_S$ decay in the minimal supersymmetric standard model at large $\tan\be$. It is shown that the Wilson coefficient $C_{8g}$ of the chromomagnetic penguin operator can…

High Energy Physics - Phenomenology · Physics 2009-11-10 Seungwon Baek

We consider the chargino contribution to the CP violation in B \to \phi K_S decay in the minimal supersymmetric standard model at large \tan\beta. It is shown that the Wilson coefficient C_{8g} of the chromomagnetic penguin operator can be…

High Energy Physics - Phenomenology · Physics 2007-05-23 Seungwon Baek

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

It is shown that the K -> pi pi matrix elements of the four-quark operator Q_7, generated by the electroweak penguin-like diagrams of the Standard Model, can be calculated to first non-trivial order in the chiral expansion and in the 1/Nc…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Knecht , S. Peris , E. de Rafael

We calculate the new contribution to the direct CP-violation parameter $\epsilon'$ in $K\to \pi\pi$ decay in the minimal left-right symmetric model with the recently-obtained right-handed quark Cabibbo-Kobayashi-Maskawa mixing. We pay…

High Energy Physics - Phenomenology · Physics 2010-04-23 Panying Chen , Hongwei Ke , Xiangdong Ji

The direct CP asymmetry $a_{CP}^{\mathrm{dir}}(D^0\rightarrow K_SK_S)$ involves exchange diagrams which are induced at tree level in the Standard Model. Since the corresponding topological amplitude $E_{KK}$ can be large, $D^0\rightarrow…

High Energy Physics - Phenomenology · Physics 2015-10-07 Ulrich Nierste , Stefan Schacht

An analysis of the CP violating asymmetry in $K^\pm \to (3\pi)^\pm$ decays in the Standard Model and, by means of the mass insertion approximation, in a wide class of possible supersymmetric extensions, is presented. We find that the…

High Energy Physics - Phenomenology · Physics 2014-11-17 G. D'Ambrosio , G. Isidori , G. Martinelli

CP violation due to interference between $K_L$ and $K_S$ decays into $\pi ^+\pi^-\gamma$ is analyzed in the Standard Model. The CP-violating parameter $\epsilon'_{+- \gamma}$, which is the difference between $\eta_{+-\gamma}$ and…

High Energy Physics - Phenomenology · Physics 2010-11-01 Hai-Yang Cheng

We present the first QCD-based calculation of hadronic matrix elements with penguin topology determining direct CP-violating asymmetries in $D^0\to \pi^-\pi^+$ and $D^0\to K^- K^+$ nonleptonic decays. The method is based on the QCD…

High Energy Physics - Phenomenology · Physics 2017-10-11 Alexander Khodjamirian , Alexey A. Petrov

We present results for Delta I=3/2 and Delta S=2 matrix elements relevant for CP violation in K->Pi Pi decays and for the K_S-K_L mass difference in the standard model and beyond. They were obtained with Neuberger fermions on quenched gauge…

We study the direct CP violation effect in the decay mode $B^+ \to \phi K^+$. This decay mode is dominated by the loop induced $\bar b \to \bar s s \bar s$ penguin diagram with a tiny contribution from annihilation diagram. Therefore, the…

High Energy Physics - Phenomenology · Physics 2009-11-10 A. K. Giri , R. Mohanta

We present an analysis of the enhancement of CP-violating charge asymmetries in $K \rightarrow 3\pi$ decays. Calculations of decay amplitudes are performed on the basis of bosonized strong and weak Lagrangians derived from QCD-motivated…

High Energy Physics - Phenomenology · Physics 2010-11-01 A. A. Bel'kov , G. Bohm , D. Ebert , A. V. Lanyov , A. Schaale

We analyze the supersymmetric contributions to direct-CP-violating observables in $K \to \pi\pi\gamma$ decays induced by gluino-mediated magnetic-penguin operators. We find that $\epsp_{+-\gamma}$ and the differential width asymmetry of…

High Energy Physics - Phenomenology · Physics 2009-10-31 G. Colangelo , G. Isidori , J. Portoles

We study the effects of the MSSM contribution on B -> phi K decays using the perturbative QCD approach. In this approach, strong phases can be calculated, so that we can predict the values of CP asymmetries with the MSSM contribution. We…

High Energy Physics - Phenomenology · Physics 2009-11-10 Satoshi Mishima , A. I. Sanda

LHCb, CDF and most recently Belle have observed a large difference between direct CP asymmetries in $D^0\to K^+K^-$ and $D^0\to\pi^+\pi^-$. We use the measured value of $\Delta A_{CP}$ to constrain the magnitude and strong phase of a…

High Energy Physics - Phenomenology · Physics 2013-02-25 Bhubanjyoti Bhattacharya

We present the calculation of $K\to\pi\pi$ matrix elements of electroweak penguin operators {\it i.e.} $Q_7$ and $Q_8$. In the numerical simulation, we use the gauge configurations generated by the combination of $N_f=2$ domain-wall…

High Energy Physics - Lattice · Physics 2009-09-29 Jun Noaki

In the presence of large New Physics contributions to loop-induced b->s transitions, sizable direct CP violation in B-> phi K decays is expected on general grounds. We compute explicitly CP-violating effects using QCD factorization and find…

High Energy Physics - Phenomenology · Physics 2009-11-07 M. Ciuchini , L. Silvestrini

We extend in several respects our earlier work on O(p^2) corrections to matrix elements of the electroweak penguin operator O_{ewp}. First, to facilitate comparison with certain lattice studies we calculate O(p^2) corrections to…

High Energy Physics - Phenomenology · Physics 2009-11-07 Vincenzo Cirigliano , Eugene Golowich

We study the correlation between $\epe$ and $\Delta I=1/2$ rule in the framework of non-linear $\sigma$ model including scalar mesons. The matrix elements of QCD and Electroweak (EW) penguin operators are computed within factorization…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Harada , Y. Keum , Y. Kiyo , T. Morozumi , T. Onogi , N. Yamada
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