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Related papers: Quarks at the modular $S_4$ cusp

200 papers

We build a class of two-Higgs-doublet models in which the flavour-changing couplings of the neutral scalars are related in an exact way to elements of the quark mixing matrix. In this framework, we explore the different possibilities for CP…

High Energy Physics - Phenomenology · Physics 2009-10-28 G. C. Branco , W. Grimus , L. Lavoura

In view of the observed strong hierarchy of quark masses, we propose a new description of flavor mixing which is particularly suited for models of quark mass matrices based on flavor symmetries. The necessary and sufficient conditions for…

High Energy Physics - Phenomenology · Physics 2010-11-23 Harald Fritzsch , Zhi-zhong Xing

In view of the observed strong hierarchy of the quark and lepton masses and of the flavor mixing angles it is argued that the description of flavor mixing must take this into account. One particular interesting way to describe the flavor…

High Energy Physics - Phenomenology · Physics 2007-05-23 Harald Fritzsch

We study quark and lepton flavor structures on magnetized $T^2/\mathbb{Z}_2$ twisted orbifold model. There are 6,460 number of flavor models but most of them cannot lead to realistic flavor observables because of the difficulties on…

High Energy Physics - Phenomenology · Physics 2024-03-27 Shota Kikuchi

We propose models in which the hierarchical structures of the masses and mixing in both quark and lepton sectors are explained by the $S_4^\prime$ modular flavor symmetry near the fixed point $\tau \sim i\infty$. The model provides the…

High Energy Physics - Phenomenology · Physics 2023-06-14 Yoshihiko Abe , Tetsutaro Higaki , Junichiro Kawamura , Tatsuo Kobayashi

We study the hierarchy of quark masses and mixings in a model based on a 5-dimensional spacetime with constant curvature of Randall-Sundrum type with two branes, where the Electroweak Symmetry Breaking is caused dynamically by the…

High Energy Physics - Phenomenology · Physics 2015-06-03 A. E. Carcamo Hernandez , Claudio O. Dib , Nicolás Neill H. , Alfonso R. Zerwekh

We propose a spontaneous A4 flavor symmetry breaking scheme implemented in a warped extra dimensional setup to explain the observed pattern of quark and lepton masses and mixings. The main advantages of this choice are the explanation of…

High Energy Physics - Phenomenology · Physics 2011-02-25 A. Kadosh , E. Pallante

In view of the observed strong hierarchy of the quark and lepton masses and of the flavor mixing angles it is argued that the description of flavor mixing must take this into account. One particular interesting way to describe the flavor…

High Energy Physics - Phenomenology · Physics 2007-05-23 Harald Fritzsch

We study the problem of modulus stabilisation in the framework of the modular symmetry approach to the flavour problem. By analysing simple UV-motivated CP-invariant potentials for the modulus $\tau$ we find that a class of these potentials…

High Energy Physics - Phenomenology · Physics 2022-04-15 P. P. Novichkov , J. T. Penedo , S. T. Petcov

The modular $A_4$ symmetry with three moduli is investigated. We assign different moduli to charged leptons, neutrinos, and quarks. We analyze these moduli at their fixed points where a residual symmetry exists. We consider two…

High Energy Physics - Phenomenology · Physics 2024-12-30 Mohammed Abbas , Shaaban Khalil

We study quark and lepton mass matrices derived from magnetized $T^2/\mathbb{Z}_2$ orbifold models. Quark and lepton masses have a large hierarchy. In addition, mixing angles are large in the lepton sector, while those are small in the…

High Energy Physics - Phenomenology · Physics 2022-12-14 Kouki Hoshiya , Shota Kikuchi , Tatsuo Kobayashi , Hikaru Uchida

In view of the observed strong hierarchy of quark masses, we discuss a new description of flavor mixing which is particularly suited for models of quark mass matrices based on flavor symmetries. The necessary and sufficient conditions for…

High Energy Physics - Phenomenology · Physics 2007-05-23 Harald Fritzsch

Recently, it was shown that modular symmetry may solve the strong CP problem without axions, by producing a vanishing QCD angle while generating a large quark CP violation phase. We extend this framework to finite modular groups,…

High Energy Physics - Phenomenology · Physics 2024-10-25 J. T. Penedo , S. T. Petcov

We show how quark and lepton mass hierarchies can be reproduced in the framework of modular symmetry. The mechanism is analogous to the Froggatt-Nielsen (FN) mechanism, but without requiring any Abelian symmetry to be introduced, nor any…

High Energy Physics - Phenomenology · Physics 2020-09-29 Simon J. D. King , Stephen F. King

We present simple effective theory of quark masses, mixing and CP violation with level $N=3$ ($A_4$) modular symmetry, which provides solution to the strong CP problem without the need for an axion. The vanishing of the strong CP-violating…

High Energy Physics - Phenomenology · Physics 2024-07-03 S. T. Petcov , M. Tanimoto

It is shown that the deconstruction of $[SU(2)\times U(1)]^N$ into $[SU(2)\times U(1)]$ is capable of providing all necessary ingredients to completely impliment the complex CKM mixing of quark flavors. The hierarchical structure of quark…

High Energy Physics - Phenomenology · Physics 2009-11-10 P. Q. Hung , A. Soddu , Ngoc-Khanh Tran

It is argued taking into account the observed mass spectra of the leptons and quarks that the phenomenon of flavor mixing is intimately related to the mass spectra. We discuss a particularly interesting way to describe the flavor mixing…

High Energy Physics - Phenomenology · Physics 2007-05-23 Harald Fritzsch

We extend the standard model with two extra Higgs doublets. Making use of a symmetry principle, we present flavour symmetries based on cycle groups $Z_N$ that oblige each Higgs doublet to contribute to the mass of only one generation, thus…

High Energy Physics - Phenomenology · Physics 2017-10-30 Nuno Rosa Agostinho , David Emmanuel-Costa , J. I. Silva-Marcos

CP violation in the CKM mixing is discussed for the case of quark mass degeneracy that is approximate in the quark mass hierarchy limit. Differing from the traditional understanding of CP vanishing for degenerate masses, we find degenerate…

High Energy Physics - Phenomenology · Physics 2024-04-30 Ying Zhang

Considered as a function of the quark mases, two-flavor QCD depends on three parameters, including one that is CP violating. As the masses vary to unphysical values, regions of both first- and second-order phase transitions are expected.…

High Energy Physics - Phenomenology · Physics 2011-10-20 Michael Creutz