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Related papers: Estimating epsilon'/epsilon in the Standard Model

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Supersymmetric extensions of the Standard Model predict a large enhancement of the Wilson coefficients of the dimension-five electromagnetic penguin operators affecting the direct CP violation in K_L --> pi^0 e^+ e^- and the charge…

High Energy Physics - Phenomenology · Physics 2016-09-06 Giancarlo D'Ambrosio , Dao-Neng Gao

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 perform a complete analysis of $\Delta S=2$ processes in the kaon system and evaluate $\Delta M_K$ and $\epsilon_K$ in the left-right supersymmetric model. We include analytic expressions for the contributions of gluinos, neutralinos and…

High Energy Physics - Phenomenology · Physics 2009-11-10 Mariana Frank , Shuquan Nie

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

Estimates of the CP violating observable $\varepsilon'/\varepsilon$ have gained some attention in the past few years. Depending on the long-distance treatment used, they exhibit up to $2.9\sigma$ deviation from the experimentally measured…

High Energy Physics - Phenomenology · Physics 2018-12-11 Jason Aebischer

CP-violating effects in the time-dependent angular distribution of the B^0_s -> J/psi[-> ell^+ ell^-] phi[-> K^+K^-] decay products play a key role for the search of new physics. The hadronic Standard-Model uncertainties are related to…

High Energy Physics - Phenomenology · Physics 2009-01-16 Sven Faller , Robert Fleischer , Thomas Mannel

The hadrodynamics of the instantaneous weak interactions (IWI) in Standard Model is considered supposing the resonance nature of the chiral hadronization of quark currents in QCD. Exploiting this supposition and QCD symmetries the IWI…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Z. Dubnickova , S. Dubnicka , V. N. Pervushin , M. Secansky

The amplitudes of $\pi$-meson decays are calculated in a relativistic nonperturbative quark model which assumes that mesons are made of a quark antiquark pair and of a scalar neutral component representing the contribution of the…

High Energy Physics - Phenomenology · Physics 2009-10-28 D. Ghilencea , L. Micu

The role of the charm quark in the dynamics underlying the \Delta I = 1/2 rule for kaon decays can be understood by studying the dependence of kaon decay amplitudes on the charm quark mass using an effective \Delta S = 1 weak Hamiltonian in…

High Energy Physics - Lattice · Physics 2012-10-23 Eric Endress , Carlos Pena

The chiral symmetry is applied to an extended constituent quark potential model. With random phase approximation (RPA), the model comprises sea quark excitations. To obtain the pseudoscalar $\pi$ meson as a Goldstone boson, the quark…

High Energy Physics - Phenomenology · Physics 2015-06-25 Weizhen Deng , Yanrui Liu , Xiaolin Chen , Dahai Lu , Shilin Zhu

The quark masses evaluated by the Particle Data Group are consistent with terms in a geometric progression of mass values descending from the Planck Mass. The common ratio of the sequence is 2/pi. The quarks occupy the 'principal' levels of…

General Physics · Physics 2007-05-23 B. F. Riley

Latest experimental progress is reviewed on the searches for physics beyond the Standard Model using the radiative and electroweak penguin decays of B mesons. This review covers inclusive and exclusive measurements of the b --> s gamma, b…

High Energy Physics - Experiment · Physics 2007-05-23 Mikihiko Nakao

In left-right models the gluonic penguin contribution to b --> s s-bar s transition is enhanced by m_t/m_b due to the presence of (V+A) currents and by the larger values of loop functions than in the Standard Model. Together those may…

High Energy Physics - Phenomenology · Physics 2009-11-07 Martti Raidal

Effective \Delta S=1 four fermion operators involving left- and right-handed currents are relevant in left-right gauge extensions of the standard model and scalar extension of the Yukawa sector. They induce K to \pi\pi\ decays which are…

High Energy Physics - Phenomenology · Physics 2015-06-16 Stefano Bertolini , Alessio Maiezza , Fabrizio Nesti

We present our latest results for the Delta I=1/2 rule, obtained on quenched ensembles with beta=6.0 and 6.2, and a set of N_f=2 configurations with beta=5.7. The statistical noise is quite under control. We observe an enhancement of the…

High Energy Physics - Lattice · Physics 2009-10-31 D. Pekurovsky , G. Kilcup

Simple dynamics, few available decay channels, and extremely well controlled radiative and loop corrections, make pion and muon decays a sensitive means for testing the underlying symmetries, the universality of weak fermion couplings, as…

Nuclear Experiment · Physics 2016-01-01 Dinko Pocanic

Recently, we developed a strategy to analyse the B -> pi pi,pi K data. We found that the B -> pi pi measurements can be accommodated in the Standard Model (SM) through large non-factorizable effects. On the other hand, our analysis of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andrzej J. Buras , Robert Fleischer , Stefan Recksiegel , Felix Schwab

The paper proposes a formal estimation procedure for parameters of the fractional Poisson process (fPp). Such procedures are needed to make the fPp model usable in applied situations. The basic idea of fPp, motivated by experimental data…

Methodology · Statistics 2018-06-08 Dexter Cahoy , Vladimir V. Uchaikin , Wojbor A. Woyczynski

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

Intriguing B --> K eta' decays provide a unique opportunity to study a joining of two-gluon configurations arising from the penguin b --> sG and b --> sGG transitions, with those inherent to the eta' particle. We employ the heavy-light…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. O. Eeg , K. Kumericki , I. Picek