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Related papers: Weakly-induced strong CP-violation

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Third order chiral perturbation theory accounts for the $\pi-N$ scattering phase shift data out to energies slightly below the position of the $\Delta$ resonance. The low energy constants are not accurately determined. Explicit inclusion of…

Nuclear Theory · Physics 2017-08-23 P. J. Ellis

In the first part of these lectures, I consider chiral perturbation theory in the presence of matter fields. It allows to systematically work out the consequences of the broken chiral symmetry of QCD. As examples, threshold pion photo- and…

High Energy Physics - Phenomenology · Physics 2015-06-25 Ulf-G. Meißner

Using chiral perturbation theory and the large-$N_c$ expansion, we obtain expressions for the $\eta'$ mass and $\eta - \eta'$ mixing in terms of low-energy chiral Lagrangian parameters. This is accomplished through an intermediate step of…

High Energy Physics - Phenomenology · Physics 2009-10-28 N. Evans , S. D. H. Hsu , M. Schwetz

The existence of $D^0-\overline{D^0}$ mixing at a detectable level requires new physics, which effectively yields a $\Delta c = 2$ superweak interaction. In general this interaction may involve significant CP violation. For small values of…

High Energy Physics - Phenomenology · Physics 2009-10-28 Lincoln Wolfenstein

These lectures are an introduction to the subject of chiral effective Lagrangians of the Standard Model and their applications, mostly in the sector of non--leptonic kaon decays, with special emphasis on CP--violation. The first lecture…

High Energy Physics - Phenomenology · Physics 2016-09-01 Eduardo de Rafael

The discovery of leptonic CP violation is one of the primary goals of next-generation neutrino oscillation experiments, which is feasible due to the recent measurement of a relatively large leptonic mixing angle \theta_{13}. We suggest two…

High Energy Physics - Phenomenology · Physics 2013-03-19 Tommy Ohlsson , He Zhang , Shun Zhou

We investigate the phenomenological constraints on a model where, besides the standard model Higgs sector, there is an effective new strong interaction acting on the third generation of quarks and characterized by a $\theta$-like term. This…

High Energy Physics - Phenomenology · Physics 2009-11-07 G. C. Branco , D. Delepine , R. Gonzalez Felipe

The reaction pi N -> pi pi N is studied at tree level up to next-to-leading order in the framework of manifestly covariant baryon chiral perturbation theory with explicit Delta(1232) degrees of freedom. Using total cross section data to…

Nuclear Theory · Physics 2014-07-09 D. Siemens , V. Bernard , E. Epelbaum , H. Krebs , Ulf-G. Meißner

The CP violating parameter epsilon'/epsilon is computed using the low-energy dynamics of a chiral theory supplemented by vector resonances. The divergent contributions coming from strong pi-pi scattering are tamed by vector-meson exchange…

High Energy Physics - Phenomenology · Physics 2014-11-17 Anirban Kundu , Emmanuel A. Paschos , Yu-Feng Zhou

We consider chiral perturbation theory (ChPT) with a non-zero theta term. Due to the CP violating term, the vacuum of chiral fields is shifted to a non-trivial element on the SU(N_f) group manifold. The CP violation also provides mixing of…

High Energy Physics - Lattice · Physics 2014-11-20 Sinya Aoki , Hidenori Fukaya

After updating the determination of the combination of Kobayashi-Maskawa elements $ \Im V_{td}V^*_{ts}$ according to our new estimate of the parameter $\hat B_K$, we study the CP-violating ratio $\epsilon'/\epsilon$ by means of hadronic…

High Energy Physics - Phenomenology · Physics 2009-10-30 S. Bertolini , J. O. Eeg , M. Fabbrichesi , E. I. Lashin

In pure chiral perturbation theory (ChPT) the couplings of higher order Lagrangian terms are running parameters and hence can be determined only empirically from various low-energy hadronic processes. While this scenario works well for…

High Energy Physics - Phenomenology · Physics 2007-05-23 Hai-Yang Cheng

I : Chiral Perturbation Theory is introduced and its applications to semileptonic and nonleptonic kaon decays are discussed. II: The method of large $N_c$ is used to calculate $K\to\pi\pi$ nonleptonic matrix elements, in particular the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Johan Bijnens

I discuss the mass parameters appearing in the gauge theory of the strong interactions, concentrating on the two flavor case. I show how the effect of the CP violating parameter $\theta$ is simply interpreted in terms of the state of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Michael Creutz

In the supersymmetric models, the dominant sources of the hadronic flavor-diagonal CP violation at low energy are the theta term and the chromoelectric dipole moments of quarks. Using QCD sum rules, we estimate the preferred range and the…

High Energy Physics - Phenomenology · Physics 2009-11-07 Maxim Pospelov

We construct a low-energy effective field theory that permits the complete treatment of isospin-breaking effects in nonleptonic weak interactions to next-to-leading order. To this end, we enlarge the chiral Lagrangian describing strong and…

High Energy Physics - Phenomenology · Physics 2009-10-31 G. Ecker , G. Isidori , G. Mueller , H. Neufeld , A. Pich

We construct a model for the weak pion production off the nucleon, which in addition to the weak excitation of the $\Delta(1232)$ resonance and its subsequent decay into $N\pi$, it includes also some background terms required by chiral…

Nuclear Theory · Physics 2008-11-26 E. Hernandez , J. Nieves , M. Valverde

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

The parity-conserving $a$ and parity-violating $b$ amplitudes for weak radiative hyperon decay are studied using chiral perturbation theory. The imaginary parts of $a$ and $b$ are computed using unitarity. The real part of $b$ is dominated…

High Energy Physics - Phenomenology · Physics 2008-11-26 Elizabeth Jenkins , Michael Luke , Aneesh V. Manohar , Martin J. Savage

These lectures introduce some of the basic notions of effective field theories, as used in particle physics. The topics discussed are the $\Delta S=1$ and $\Delta S =2$ weak interactions, and chiral perturbation theory as applied to mesons,…

High Energy Physics - Phenomenology · Physics 2007-05-23 Aneesh V. Manohar