English

A dynamical CP source for CKM, PMNS and Leptogenesis

High Energy Physics - Phenomenology 2013-09-03 v3

Abstract

We propose a simple model for the spontaneous CP violation based on SU(2)L×U(1)Y×A4×CP×Z2SU(2)_{L}\times U(1)_{Y}\times A_{4}\times CP\times Z_{2} symmetry for quarks and leptons in a seesaw framework. In our model CP is spontaneously broken at high energies, after breaking of flavor symmetry, by a complex vacuum expectation value of A4A_{4}-triplet and gauge singlet scalar field. And, certain effective dimension-5 operators are introduced in the quark Lagrangian as an equal footing, which lead the quark mixing matrix to the Cabibbo-Kobayashi-Maskawa (CKM) one in the form, while the lepton Lagrangian is renormalizable, which gives rise to a non-degenerate Dirac neutrino Yukawa matrix and an unique CP-phase, and which in turn explains the non-zero value of θ139\theta_{13}\simeq9^{\circ} and two large mixing angles θ12,θ23\theta_{12}, \theta_{23}. We show that the spontaneously generated CP phase "ξ\xi" could become a natural source of leptogenesis as well as CP violations in the CKM and Pontecorvo-Maki-Nakagawa-Sakata (PMNS). Moreover, we provide a solution for the strong CP problem. Interestingly enough, we show that, for around ξ120\xi\simeq120^{\circ}, the quarks lead to the correct CKM CP-phase corresponding to δCPq67\delta^{q}_{CP}\simeq67^{\circ}, while the leptons with the measured value of θ13\theta_{13} favor δCP=\delta_{CP}=, θ23450|\theta_{23}-45^{\circ}|\rightarrow0 for normal mass hierarchy and δCP=\delta_{CP}=, θ23455|\theta_{23}-45^{\circ}|\rightarrow5^{\circ} for inverted one. As a numerical study in the lepton sector, we show low-energy phenomenologies and leptogenesis for the normal and inverted case, respectively, and a link between them.

Keywords

Cite

@article{arxiv.1306.4138,
  title  = {A dynamical CP source for CKM, PMNS and Leptogenesis},
  author = {Y. H. Ahn and Seungwon Baek},
  journal= {arXiv preprint arXiv:1306.4138},
  year   = {2013}
}

Comments

40 pages, 11 figures; version published in Phys. Rev. D. arXiv admin note: substantial text overlap with arXiv:1207.1229, arXiv:1304.0921, arXiv:1303.4863

R2 v1 2026-06-22T00:35:41.358Z