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Related papers: CP, or not CP, that is the question...

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We review basic aspects of the phenomenology of CP violation in the decays of $K$ and $B$ mesons. In particular we discuss the commonly used classification of CP violation -- CP violation in the mass matrix, in the interference of mixing…

High Energy Physics - Phenomenology · Physics 2009-10-30 Gerhard Buchalla

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

CP violation is one of Sakharov's conditions for the matter-antimatter asymmetry of the Universe. The experimentally observed size of CP violation is insufficient to account for this. Is CP violated in the Higgs sector? Could the SM-like…

The mechanism of CP violation remains one of the puzzles in particle physics. Key to understanding this phenomenon are nonleptonic $B$ decays, especially multibody decays which exhibit large CP asymmetries in various regions of phase space.…

High Energy Physics - Phenomenology · Physics 2020-07-15 Thomas Mannel , Kevin Olschewsky , K. Keri Vos

We study $SU(3)$ flavor-breaking corrections to the relation between the octet baryon masses and the nucleon-meson CP-violating interactions induced by the QCD $\bar\theta$ term. We work within the framework of $SU(3)$ chiral perturbation…

Nuclear Theory · Physics 2015-11-18 Jordy de Vries , Emanuele Mereghetti , Andre Walker-Loud

Supersymmetric models with nonuniversal down type squark masses can enrich the chiral structure and CP violating phenomena in $b\to s\gamma$ decays. Direct CP violation in $b\to s \gamma$, mixing induced CP violation in radiative $B_{d,s}$…

High Energy Physics - Phenomenology · Physics 2016-08-25 Chun-Khiang Chua , Xiao-Gang He , Wei-Shu Hou

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 T' group as the family symmetry. The complex CG coefficients in T' lead…

High Energy Physics - Phenomenology · Physics 2009-11-19 Mu-Chun Chen , K. T. Mahanthappa

Several topics on CP violation in the lepton sector are reviewed. A few theoretical aspects concerning neutrino masses, leptonic mixing, and CP violation will be covered, with special emphasis on seesaw models. A discussion is provided on…

High Energy Physics - Phenomenology · Physics 2015-06-03 G. C. Branco , R. Gonzalez Felipe , F. R. Joaquim

We argue that CP violation has rather dramatic impact on the "gravity as the weakest force" conjecture. Namely we find that new ultraviolet scale must be $\Lambda \lesssim \theta g^3 M_P$, where $\theta$ is an effective parameter describing…

High Energy Physics - Theory · Physics 2008-07-05 Archil Kobakhidze

In a recent paper[1] Kundu and one of the present authors showed that there were transient but observable CP violating effects in the decay of classical currents on the horizon of a black hole, if the Lagrangian of the Maxwell field…

High Energy Physics - Theory · Physics 2015-05-19 Tom Banks , Willy Fischler

We review CP properties of the Two-Higgs-Doublet model. In particular, we show that spontaneous CP violation occurs in the parameter space on the border between regions allowing explicit CP violation and those where there is another…

High Energy Physics - Phenomenology · Physics 2015-04-28 B. Grzadkowski , O. M. Ogreid , P. Osland

We review and clarify some cases of geometrical CP violation, the framework of spontaneous CP violation through complex phases with values that are independent of parameters of the potential. We present a flavour model based on Delta(27)…

High Energy Physics - Phenomenology · Physics 2013-02-19 Ivo de Medeiros Varzielas

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

In this chapter we introduce the $\theta$-dependence and the topological properties of QCD, features of the strongly interacting sector which give rise to the strong CP problem in the more general context of the Standard Model of particle…

High Energy Physics - Lattice · Physics 2026-03-27 Claudio Bonanno , Claudio Bonati , Massimo D'Elia

These lecture notes provide a self-contained, graduate-level introduction to the strong $CP$ problem and QCD axion physics from an effective field theory (EFT) viewpoint. We review the construction of the chiral EFT of QCD yielding a…

High Energy Physics - Phenomenology · Physics 2026-02-05 Francesco Sannino

The non-perturbative implications of BRST quantization are examined for $\theta$ vacua and related issues. Strong CP violation is shown to be absent for QCD in the BRST formalism. Previous evidence for CP violation is reexamined, and much…

High Energy Physics - Phenomenology · Physics 2007-05-23 Hidenaga Yamagishi , Ismail Zahed

Axions are introduced to explain the observed smallness of the $\bar \theta $ term of QCD. Standard Model extensions typically contain new sources of CP violation, for instance to account for the baryon asymmetry of the universe. In the…

High Energy Physics - Phenomenology · Physics 2022-07-13 W. Dekens , J. de Vries , S. Shain

We review the present status of CP violating problem in supersymmetric extensions of the standard model. We analyze the constraints imposed by the experimental limits of the electron, neutron, and mercury electric dipole moments on the…

High Energy Physics - Phenomenology · Physics 2014-11-17 Shaaban Khalil

The consideration of chirality-preserving 2-fermion order parameters may shed new light on the strong CP problem and the breakdown of flavor symmetries. We describe two situations, one having the standard KM picture for weak CP violation…

High Energy Physics - Phenomenology · Physics 2009-12-30 B. Holdom

The role of a chiral U(1) phase in the quark mass in QCD is analysed from first principles. In operator formulation, there is a parity symmetry and the phase can be removed by a change in the representation of the Dirac gamma matrices.…

High Energy Physics - Phenomenology · Physics 2015-06-25 H. Banerjee , D. Chatterjee , P. Mitra