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Related papers: Weakly-induced strong CP-violation

200 papers

Assuming SU(3) symmetry for the strong phases in the four decay modes $B\rarrow \pi^-\pi^+, \pi^0 \pi^+, \pi^- K^+, \pi^- \bar{K}^0$ and ignoring the relative small electroweak penguin effects in those decays, the weak phase $\gamma$ and…

High Energy Physics - Phenomenology · Physics 2014-11-17 Yue-Liang Wu , Yu-Feng Zhou

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. The 1/N_c…

High Energy Physics - Phenomenology · Physics 2014-11-17 T. Hambye , G. O. Koehler , E. A. Paschos , P. H. Soldan

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 the theoretical and experimental status of the CP violating ratio eps'/eps. We revise our 1997 standard-model estimate-based on hadronic matrix elements computed in the chiral quark model up to O(p^4) in the chiral expansion-by…

High Energy Physics - Phenomenology · Physics 2014-11-17 Stefano Bertolini , Jan O. Eeg , Marco Fabbrichesi

The known isospin-breaking contributions to the $K\rightarrow \pi\pi$ amplitudes are reanalyzed, taking into account our current understanding of the quark masses and the relevant non-perturbative inputs. We present a complete numerical…

High Energy Physics - Phenomenology · Physics 2020-03-18 V. Cirigliano , H. Gisbert , A. Pich , A. Rodríguez-Sánchez

We report on some recent progress made in understanding weak matrix elements of mesons in the context of the next-to-leading order of the large-Nc approximation to QCD. Specifically, we first use the example of the weak contributions to the…

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

We present a new calculation of long-distance contributions to the K --> pi pi amplitudes using the 1/N_c expansion within the framework of chiral perturbation theory. Along these lines we compute the chiral loop corrections to the…

High Energy Physics - Phenomenology · Physics 2007-05-23 G. O. Koehler

Effective field theory techniques are used to describe the interaction of heavy hadrons in a model independent way. Predictability is obtained by exploiting the symmetries of QCD. Heavy hadron chiral perturbation theory is reviewed and used…

High Energy Physics - Phenomenology · Physics 2007-05-23 Iain W. Stewart

Two-point functions related to the pion weak decay constant f_\pi are calculated from the generating functional of chiral perturbation theory in the mean-field approximation and the heavy-baryon limit. The aim is to demonstrate that Lorentz…

High Energy Physics - Phenomenology · Physics 2007-05-23 Mariana Kirchbach , Andreas Wirzba

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

The ten nonleptonic weak decays $K \to 2\pi$, $K \to 3\pi$, $K_L \to 2\gamma$, $K_S \to 2\gamma$, $K_L \to \pi^\circ 2\gamma$, are predicted for a chiral pole model based on the linear sigma model theory which automatically satisfies the…

High Energy Physics - Phenomenology · Physics 2011-07-19 M. D. Scadron

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

On the basis of a next-to-leading-order calculation in chiral perturbation theory, the first complete analysis of isospin breaking for direct CP violation in K^0 -> 2 pi decays is performed. We find a destructive interference between three…

High Energy Physics - Phenomenology · Physics 2009-11-10 V. Cirigliano , A. Pich , G. Ecker , H. Neufeld

In this paper we determine the weak-interaction corrections of order $\alpha_s^2\alpha$ to hadronic top-quark pair production. First we compute the one-loop weak corrections to $t \bar t$ production due to gluon fusion and the order…

High Energy Physics - Phenomenology · Physics 2008-11-26 Werner Bernreuther , Michael Fuecker , Zong-Guo Si

Tests of CP violation by appropriate momentum correlations in $Z\to 3$ jets and in particular in $Z\to b\bar bX$ probe CP-violating effective couplings -- that manifest themselves as form factors -- which conserve the quark chirality and…

High Energy Physics - Phenomenology · Physics 2009-10-28 W. Bernreuther , A. Brandenburg , P. Haberl , O. Nachtmann

Motivated by the phenomenological scenario of the chiral magnetic effect that can be possibly found in high-energy heavy ion collisions, we study the role of very intense magnetic fields and strong CP violation in the phase structure of…

High Energy Physics - Phenomenology · Physics 2010-02-11 Eduardo S. Fraga , Ana Júlia Mizher

We present new results for the matrix elements of the Q_6 and Q_4 penguin operators, evaluated in a large-Nc approach which incorporates important O(N_c^2\frac{n_f}{N_c}) unfactorized contributions. Our approach shows analytic matching…

High Energy Physics - Phenomenology · Physics 2010-02-03 T. Hambye , S. Peris , E. de Rafael

We consider the low-energy effects of a selected set of Lorentz- and CPT-violating quark and gluon operators by deriving the corresponding chiral effective lagrangian. Using this effective lagrangian, low-energy hadronic observables can be…

High Energy Physics - Phenomenology · Physics 2016-07-21 J. P. Noordmans

We construct the vector and axial vector currents in Wilson Chiral Perturbation Theory (WChPT), the low-energy effective theory for lattice QCD with Wilson fermions. Our construction is slightly different compared to ChPT in continuum QCD,…

High Energy Physics - Lattice · Physics 2009-04-14 Sinya Aoki , Oliver Bar

A dynamical scheme where the third generation of quarks plays a distinctive role is implemented. New interactions with a $\theta$ term induce the breaking of the electroweak symmetry and the top-bottom mass splitting. A large CP-violating…

High Energy Physics - Phenomenology · Physics 2009-10-30 D. Delepine , J. -M. Gerard , R. Gonzalez Felipe , J. Weyers