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Related papers: Strong CP, Flavor, and Twisted Split Fermions

200 papers

We present a top-condensation model in which the CP symmetry is spontaneously broken at the electroweak scale due to the condensation of two composite Higgs doublets. In particular the CP-violating phase of the CKM matrix is generated. A…

High Energy Physics - Phenomenology · Physics 2009-11-11 Cristian Valenzuela

We study the contributions of supersymmetric models with a $U(1)$ horizontal symmetry and only spontaneous CP breaking to various lepton flavor observables, such as $\mu \to e\gamma$ and the electron electric dipole moment. We show that…

High Energy Physics - Phenomenology · Physics 2021-12-16 Daniel Aloni , Pouya Asadi , Yuichiro Nakai , Matthew Reece , Motoo Suzuki

CP violation is observed to date only in K^0 decays and is parameterizable by a single quantity epsilon. Because it is one of the least understood phenomena in the Standard Model and holds a clue to baryogenesis, it must be investigated…

High Energy Physics - Phenomenology · Physics 2008-11-26 Isard Dunietz

As we pointed out recently, the neutral decays $B_d\to\pi^\mp K^\pm$ and $B_d\to\pi^0K$ may provide non-trivial bounds on the CKM angle $\gamma$. In this paper, we reconsider this approach in the light of recent CLEO data, which look very…

High Energy Physics - Phenomenology · Physics 2008-11-26 Andrzej J. Buras , Robert Fleischer

In this manuscript, a way solves the FCNC problem in 2HDM radically and leads to CP violation explicitly is demonstrated. The derivation starts from a most general $3 \times 3$ mass matrix $M$ containing eighteen parameters, which applies…

High Energy Physics - Phenomenology · Physics 2018-11-08 Chilong Lin

The Nelson-Barr (NB) mechanism to solve the strong CP problem assumes CP conservation, arranges vanishing $\bar{\theta}$ at tree-level and requires vector-like quarks (VLQs) to transmit the CP breaking to the SM. We analyze the flavor…

High Energy Physics - Phenomenology · Physics 2021-11-19 A. L. Cherchiglia , G. De Conto , C. C. Nishi

We analyze possible interpretations of the recent LHCb evidence for CP violation in D meson decays in terms of physics beyond the Standard Model. On general grounds, models in which the primary source of flavor violation is linked to the…

High Energy Physics - Phenomenology · Physics 2015-06-04 Gian Francesco Giudice , Gino Isidori , Paride Paradisi

We argue that the Nelson-Barr solution to the Strong CP Problem can be naturally realized in an E$_6$ Grand-Unified Theory. The chiral SM fermions reside in three generations of E$_6$ fundamentals together with heavy vectorlike down quarks,…

High Energy Physics - Phenomenology · Physics 2018-12-05 Jakob Schwichtenberg , Paul Tremper , Robert Ziegler

The possibility of spontaneous breaking of CP symmetry by the expectation values of orbifold moduli is investigated with particular reference to $CP$ violating phases in soft supersymmetry breaking terms. The effect of different mechanisms…

High Energy Physics - Theory · Physics 2014-11-18 D. Bailin , G. V. Kraniotis , A. Love

We discussed the scenario that a discrete flavor group combined with CP symmetry is broken to $Z_2\times CP$ in both neutrino and charged lepton sectors. All lepton mixing angles and CP violation phases are predicted to depend on two free…

High Energy Physics - Phenomenology · Physics 2018-04-04 Cai-Chang Li , Jun-Nan Lu , Gui-Jun Ding

The strong CP problem is one of many puzzles in the theoretical description of elementary particle physics that still lacks an explanation. While top-down solutions to that problem usually comprise new symmetries or fields or both, we want…

High Energy Physics - Phenomenology · Physics 2018-05-17 J. L. Díaz-Cruz , W. G. Hollik , U. J. Saldaña-Salazar

Models that combine Abelian horizontal symmetries and spontaneous CP violation can (i) explain the smallness and hierarchy in quark parameters; (ii) satisfactorily suppress supersymmetric contributions to flavor changing neutral current…

High Energy Physics - Phenomenology · Physics 2009-10-28 Yosef Nir , Riccardo Rattazzi

In the simplest version of a $\mathbf{Q}_{6}$ flavored supersymmetric model, we analyze the leptonic masses and mixings in the framework of a soft breaking of the $\mu \leftrightarrow \tau$ symmetry. This breaking is controlled by the…

High Energy Physics - Phenomenology · Physics 2017-10-18 Juan Carlos Gómez-Izquierdo , F. Gonzalez-Canales , M. Mondragón

We discuss the phenomenology of effective field theories with new scalar or vector representations of the Standard Model quark flavor symmetry group, allowing for large flavor breaking involving the third generation. Such field content can…

High Energy Physics - Phenomenology · Physics 2015-05-30 Benjamin Grinstein , Alexander L. Kagan , Michael Trott , Jure Zupan

We suggest a new solution to the strong CP problem. The solution is based on the proper use of the boundary conditions for the QCD generating functional integral. We expand the perturbative boundary conditions to both perturbative and…

High Energy Physics - Phenomenology · Physics 2023-12-19 S. A. Larin

We propose a phenomenological model of lepton mixing and CP violation based on the flavor democracy of charge leptons and the mass degeneracy of neutrinos. A nearly bi-maximal flavor mixing pattern, which is favored by current data on…

High Energy Physics - Phenomenology · Physics 2007-05-23 Harald Fritzsch , Zhi-zhong Xing

We propose that the flavor structure of the quark sector of the Standard Model is determined by a vectorial SU(2) flavor symmetry, which we dub Flavorspin, under which quarks transform as triplets. The fundamental Yukawa couplings are real…

High Energy Physics - Phenomenology · Physics 2015-07-03 Jeffrey Berryman , Daniel Hernández

In this talk we report on a study on the mixing of neutral charmed mesons and argue that, at the present stage, a CP violating weak phase of the order of some per mille can not be excluded in the Standard Model. It is shown how some,…

High Energy Physics - Phenomenology · Physics 2011-04-22 Markus Bobrowski , Alexander Lenz

We show that string models with low energy supersymmetry which accommodate the fermion mass hierarchy generally give non-universal soft trilinear couplings (A-terms). In conjunction with the apparently large Cabibbo-Kobayashi-Maskawa (CKM)…

High Energy Physics - Phenomenology · Physics 2009-12-04 S. Abel , S. Khalil , O. Lebedev

It is well known that the CP violating theta term of QCD can be converted to a phase in the quark mass term. However, a theory with a complex mass term for quarks can be regularized so as not to violate CP, for example through a zeta…

High Energy Physics - Theory · Physics 2008-11-26 P. Mitra