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Related papers: Nelson-Barr Models with Vector-Like Quark Doublets

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Scalar triplet extensions of the Standard Model provide an interesting playground for the explanation of neutrino mass suppression through the type-II seesaw mechanism. Propelled by the possible connections with leptonic CP violation, we…

High Energy Physics - Phenomenology · Physics 2022-06-08 P. M. Ferreira , B. L. Gonçalves , F. R. Joaquim

Models which solve the strong CP problem by employing discrete spacetime symmetries generically suffer fine-tuning and quality problems. We demonstrate that these issues are greatly ameliorated when the only source of spontaneous CP…

High Energy Physics - Phenomenology · Physics 2026-03-27 Csaba Csáki , Samuel Homiller , Taewook Youn

We investigate a composite model of spontaneous CP violation based on a new supersymmetric QCD as a solution to the strong CP problem. The scalar components of the meson chiral superfields obtain complex vacuum expectation values to break…

High Energy Physics - Phenomenology · Physics 2024-06-04 Shota Nakagawa , Yuichiro Nakai , Yaoduo Wang

We build a model containing two scalar doublets and a scalar singlet with a specific discrete symmetry. After spontaneous symmetry breaking, the model has Standard Model-like phenomenology, as well as a hidden scalar sector which provides a…

High Energy Physics - Phenomenology · Physics 2018-12-05 Duarte Azevedo , P. M. Ferreira , M. Margarete Muhlleitner , Shruti Patel , Rui Santos , Jonas Wittbrodt

CP invariance is a very attractive solution to the strong CP problem in QCD. This solution requires the vanishing ${\rm arg}\,[{\rm det}\, M_d\, {\rm det} M_u]$, where the $M_d$ and $M_u$ are the mass matrices for the down- and up-type…

High Energy Physics - Phenomenology · Physics 2025-10-22 Morimitsu Tanimoto , Tsutomu T. Yanagida

We propose a new mechanism called "real CP violation" to originate spontaneous CP violation. Starting with a CP conserving theory with scalar fields in the adjoint representation of a global or local non-abelian symmetry, we show that even…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Masiero , T. Yanagida

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

CP violation of the SM is insufficient to explain the baryon asymmetry in the universe and therefore an additional source of CP violation is needed. Here the extension of the SM by a neutral complex scalar singlet with a nonzero vacuum…

High Energy Physics - Phenomenology · Physics 2017-10-03 Neda Darvishi

We investigate the possibilities of searching for non-standard CP violation in $pp\to t\bar{t}X$ at multiple TeV collision energies. A general kinematic analysis of the underlying partonic production processes $gg\to t\bar{t}$ and…

High Energy Physics - Phenomenology · Physics 2014-11-17 W. Bernreuther , A. Brandenburg

We propose a model of spontaneous CP violation to address the strong CP problem in warped extra dimensions that relies on sequestering flavor and CP violation. We assume that brane-localized Higgs Yukawa interactions respect a U(3) flavor…

High Energy Physics - Theory · Physics 2009-01-06 Clifford Cheung , A. Liam Fitzpatrick , Lisa Randall

Violated mirror symmetry (MS) is capable of reproducing observed qualitative properties of weak mixing for quarks and leptons. In violated MS, lepton phenomenology, that is, small neutrino masses and mixing properties different from those…

High Energy Physics - Phenomenology · Physics 2017-05-24 Igor T. Dyatlov

We study on the electroweak baryogenesis problem in the vector-like quark model. This model can add to the minimal standard model the extra CP-violation source which breaks CP spontaneously. Using charge transport mechanism suggested by…

High Energy Physics - Phenomenology · Physics 2007-05-23 Tomoko Uesugi

We find a solution to the Strong CP problem that may be testable at the LHC and future colliders. In this solution CP is broken by parity conserving terms, while parity breaking VEVs conserve CP. The quark mass matrix is Hermitian at the…

High Energy Physics - Phenomenology · Physics 2011-01-05 Ravi Kuchimanchi

We analyse the general constraints on unified gauge models with spontaneous CP breaking that satisfy the conditions that (i) CP violation in the quark sector is described by a realistic complex CKM matrix, and (ii) there is no significant…

High Energy Physics - Phenomenology · Physics 2008-11-26 G. C. Branco , R. N. Mohapatra

We readdress the issue of strong CP violation both in the Standard Model and in the Minimal Left-Right Symmetric Model and try to clear the confusion that seems to still pervade the field. We argue that the smallness of strong CP violation,…

High Energy Physics - Phenomenology · Physics 2020-06-15 Goran Senjanovic , Vladimir Tello

The spontaneous CP-violation in three kinds of extension of the standard model are investigated. We find that if no additional symmetry is introduced to reduce the number of coefficients, then all three extended models possess the…

High Energy Physics - Phenomenology · Physics 2010-11-01 Chilong Lin , Chien-er Lee , Yeou-Wei Yang

We propose a minimal modification of the standard model, remarkable in its simplicity, which may solve the strong CP problem. It employs three Higgs doublets with interactions taken to be invariant under a flavor symmetry. Both CP and the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Sheldon Lee Glashow

In multi-Higgs-doublet models, requiring simultaneously that (i) CP violation only arises spontaneously, (ii) tree level scalar flavour changing couplings are absent and (iii) the fermion mixing matrix is CP violating, can only be achieved…

High Energy Physics - Phenomenology · Physics 2023-10-20 João M. Alves , Francisco J. Botella , Carlos Miró , Miguel Nebot

We explore a concrete realization of a Nelson-Barr model addressing the strong CP problem with suppressed unfavorable corrections. This model has a scalar field that spontaneously breaks discrete symmetry, and its phase component can…

High Energy Physics - Phenomenology · Physics 2024-12-30 Kai Murai , Kazunori Nakayama

Three symmetry constraints on the CP violations in QCD are discussed in this paper. In order to generate CP violating observables from QCD, these constraints require: (1) spontaneous chiral symmetry breaking, (2) explicit chiral symmetry…

High Energy Physics - Phenomenology · Physics 2007-05-23 Chuan-Tsung Chan