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Related papers: Weakly-induced strong CP-violation

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There is an important connection between the low energy theorems of QCD and the energy dependence of the Delta resonance in pi-N scattering, as well as the closely related gamma^{*} N -> pi N reaction. The resonance shape is due not only to…

High Energy Physics - Phenomenology · Physics 2015-03-13 A. M. Bernstein , S. Stave

CP-violation in $\Delta A_{\textrm {CP}} = -0.154(29)$, in the $D^0 \to \pi^+\pi^-/K^+K^-$ system, is established and its central value is one order of magnitude above the naive Standard Model (SM) estimate. It remains unclear whether this…

High Energy Physics - Phenomenology · Physics 2022-08-17 James Lyon , Roman Zwicky

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

Interactions of $a_2, K^*_2, f_2$ and $f_2'$ tensor-mesons with low-energy $\pi, K, \eta, \eta'$ pseudo-scalar mesons are constrained by chiral symmetry. We derive a chiral Lagrangian of tensor mesons in which the tensor mesons are treated…

High Energy Physics - Phenomenology · Physics 2010-02-03 Chi-Keung Chow , Soo-Jong Rey

We perform a complete analysis of isospin breaking in K -> Pi Pi amplitudes in chiral perturbation theory, including both strong isospin violation and electromagnetic corrections to next-to-leading order in the low-energy expansion. The…

High Energy Physics - Phenomenology · Physics 2014-11-17 V. Cirigliano , G. Ecker , H. Neufeld , A. Pich

We study the low-energy properties of QCD-like theories in the presence of a $P$-odd and $U(1)$ axial breaking four-fermion operator $\left( \bar{\psi} \psi \right) \left( \bar{\psi} i \gamma_5 \psi \right)$. We apply the functional…

High Energy Physics - Phenomenology · Physics 2026-05-28 Yuepeng Guan , Shinya Matsuzaki , Masatoshi Yamada

We analyze the theoretical implications of the new KTeV measurement of direct CP-violation in K->pi pi decays. The result is found consistent with the Standard Model for low values of the strange quark mass m_s. If the hadronic parameters…

High Energy Physics - Phenomenology · Physics 2014-11-17 Y. -Y. Keum , U. Nierste , A. I. Sanda

The aim of this introductory lecture is to review the arguments, according to which the symmetry properties of the strong interaction reveal themselves at low energies. I first discuss the symmetries of QCD, then sketch the method used to…

High Energy Physics - Phenomenology · Physics 2009-10-28 H. Leutwyler

We use power-counting arguments as an organizing principle to apply chiral perturbation theory, including an explicit $\Delta$, to the $p p \rightarrow p p \pi^0$ reaction near threshold. There are two lowest-order leading mechanisms…

Nuclear Theory · Physics 2008-11-26 T. D. Cohen , J. L. Friar , G. A. Miller , U. van Kolck

We examine CP-violating effects on electroweak phase transition (EWPT) in the standard model with a complex singlet scalar focusing particularly on a scenario where additional scalars have masses close to 125 GeV. Such a high mass…

High Energy Physics - Phenomenology · Physics 2022-12-21 Gi-Chol Cho , Chikako Idegawa , Eibun Senaha

We compute the leading-order low-energy constants of the DeltaS=1 effective weak Hamiltonian in the quenched approximation of QCD with up, down, strange, and charm quarks degenerate and light. They are extracted by comparing the predictions…

High Energy Physics - Phenomenology · Physics 2008-11-26 L. Giusti , P. Hernandez , M. Laine , C. Pena , J. Wennekers , H. Wittig

CP-violating signals in weak $ \Xi\to \pi \Lambda$ decay require the knowledge of $\pi \Lambda$ $S$- and $P$-wave scattering phases at ${m}_{\Xi}$ center-of-mass energy. We have calculated these phases in baryon chiral perturbation theory…

High Energy Physics - Phenomenology · Physics 2016-08-25 A. N. Kamal

We find using the minimal left-right symmetric model that the presence of leptonic CP violation can radiatively generate a strong CP phase at the one-loop level itself, which can be beyond the current bounds established by the neutron…

High Energy Physics - Phenomenology · Physics 2015-04-29 Ravi Kuchimanchi

We estimate the CP-violating $WW\gamma$ and $WWZ$ anomalous form factors, arising from CP-violating interactions in extended technicolor theories, and discuss their future experimental detectability. The electric dipole moment of the $W$…

High Energy Physics - Phenomenology · Physics 2010-11-01 Thomas Appelquist , Guo-Hong Wu

We derive sufficient conditions that guarantee a robust solution of the strong CP problem in theories with spontaneous CP violation, and introduce a class of models satisfying these requirements. In the simplest scenarios the dominant…

High Energy Physics - Phenomenology · Physics 2014-12-15 Luca Vecchi

In this Ph.D. Thesis we analyze some CP-violating observables in Kaon decays. In Chapters 1-3 we describe the framework in which this Thesis has been developed and establish the definitions and notation. In Chapter 4 we study CP-violating…

High Energy Physics - Phenomenology · Physics 2007-05-23 Elvira Gamiz

Power-counting arguments are used to organize the interactions contributing to the N N -> d pi, p n pi reactions near threshold. We estimate the contributions from the three formally leading mechanisms: the Weinberg-Tomozawa (WT) term, the…

Nuclear Theory · Physics 2009-10-31 C. A. da Rocha , G. A. Miller , U. van Kolck

We investigate a controversial issue on the measure of CP violation in strong in teractions. In the presence of nontrivial topological gauge configurations, the $\theta$-term in QCD has a profound effect: it breaks the CP symmetry. The…

High Energy Physics - Phenomenology · Physics 2010-11-01 Zheng Huang

We propose the complex group theoretical Clebsch-Gordon coefficients as a novel origin of CP violation. This is manifest in our model based on SU(5) combined with the double tetrahedral group, T'. Due to the presence of the doublet…

High Energy Physics - Phenomenology · Physics 2015-05-14 Mu-Chun Chen , K. T. Mahanthappa

Complete next-to-leading (chiral) order (NLO) expressions for the strong isospin-breaking (IB) contributions in K -> pi pi are used to discuss (1) for CP-even, the impact on the magnitude of the Delta I=1/2 Rule, and (2) for CP-odd, the…

High Energy Physics - Phenomenology · Physics 2009-10-31 C. E. Wolfe , K. Maltman
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