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Related papers: Flavour physics without flavour symmetries

200 papers

In multi-Higgs-doublet models, the alignment in flavour space of all Yukawa matrices coupling to a given right-handed fermion guarantees the absence of tree-level flavour-changing neutral couplings, while introducing new sources of CP…

High Energy Physics - Phenomenology · Physics 2011-04-05 Antonio Pich

To explain quark and lepton masses and mixing angles, one has to extend the standard model, and the usual practice is to put the quarks and leptons into irreducible representations of discrete groups. We argue that discrete flavor…

High Energy Physics - Phenomenology · Physics 2016-04-27 Carl H. Albright , Robert P. Feger. , Thomas W. Kephart

We explore the possibility that lepton family numbers and baryon number are such good symmetries of Nature because they are the global remnant of a spontaneously broken gauge symmetry. An almost arbitrary linear combination of these…

High Energy Physics - Phenomenology · Physics 2020-01-15 Wolfgang Altmannshofer , Joe Davighi , Marco Nardecchia

We derive predictions for Yukawa coupling ratios within GUTs generated from operators with mass dimension four and five. These relations are a characteristic property of unified flavour models and can reduce the large number of free…

High Energy Physics - Phenomenology · Physics 2010-09-15 Martin Spinrath

We propose that the electroweak and flavour quantum numbers of the Standard Model (SM) could be unified at high energies in an $SU(4)\times Sp(6)_L \times Sp(6)_R$ anomaly-free gauge model. All the SM fermions are packaged into two…

High Energy Physics - Phenomenology · Physics 2022-10-19 Joe Davighi , Joseph Tooby-Smith

The Standard Model lacks an organizing principle to describe quark and lepton ``flavours''. Neutrino oscillation experiments show that leptons mix very differently from quarks, adding a major challenge to the flavour puzzle. We briefly…

High Energy Physics - Phenomenology · Physics 2025-02-04 Gui-Jun Ding , Jose W. F. Valle

We examine possibilities for the radiative generation of the Yukawa couplings and flavour structure in supersymmetric models in the supersymmetric phase. Not withstanding the non-renormalisation of the Wilsonian superpotential, this can…

High Energy Physics - Theory · Physics 2015-05-30 Joseph P. Conlon , Francisco G. Pedro

A general operator expansion is presented for quark and lepton mass matrices in unified theories based on a U(2) flavor symmetry, with breaking parameter of order $V_{cb} \approx m_s/m_b \approx \sqrt{m_c/m_t}$. While solving the…

High Energy Physics - Phenomenology · Physics 2009-10-30 R. Barbieri , L. J. Hall , S. Raby , A. Romanino

The quark sector of the Standard Model exhibits an approximate U(2)^3 flavour symmetry. This symmetry, broken in specific directions dictated by minimality, can explain the success of the Cabibbo-Kobayashi-Maskawa picture of flavour mixing…

High Energy Physics - Phenomenology · Physics 2017-08-23 Riccardo Barbieri , Dario Buttazzo , Filippo Sala , David M. Straub

Beyond Standard Model physics frequently connects flavor symmetry with a discrete group. If the discrete symmetry arises spontaneously from a gauge theory, one can maintain compatibility with quantum gravity and avoid anomalies. We provide…

High Energy Physics - Phenomenology · Physics 2018-12-18 Bradley L. Rachlin , Thomas W. Kephart

In the formalism of the non-supersymmetric modular invariance approach to the flavour problem the elements of the Yukawa coupling and fermion mass matrices are expressed in terms of polyharmonic Maa{\ss} modular forms of level $N$ in…

High Energy Physics - Phenomenology · Physics 2024-08-29 Gui-Jun Ding , Jun-Nan Lu , S. T. Petcov , Bu-Yao Qu

We study the implications of single leptoquark extensions of the Standard Model (SM) under the assumption that their enhanced Yukawa sectors are invariant under global Abelian flavour symmetries already present in SM mass terms. Such…

High Energy Physics - Phenomenology · Physics 2022-10-19 Ivo de Medeiros Varzielas , Jim Talbert

The combination of flavor symmetries with grand unification is considered: GUT $ \times$ flavor . To accommodate three generations the flavor group SO(3) is used. All fermions transform as 3-vectors under this group. The Yukawa couplings…

High Energy Physics - Phenomenology · Physics 2011-01-07 Berthold Stech

The Yukawa interactions of the SO(10) GUT with fermions in 16-plets (as well as with singlets) have certain intrinsic ("built-in") symmetries which do not depend on the model parameters. Thus, the symmetric Yukawa interactions of the 10 and…

High Energy Physics - Phenomenology · Physics 2016-07-20 Borut Bajc , Alexei Yu. Smirnov

Flavour symmetries have been used to constrain both quark and lepton mixing parameters. In particular, they can be used to completely fix the mixing angles. For the lepton sector, assuming that neutrinos are Majorana particles, we have…

High Energy Physics - Phenomenology · Physics 2014-10-16 Renato M. Fonseca , Walter Grimus

Based on a new approach to quark and lepton masses, where the mass spectra originate in vacuum expectation values of O(3)-flavor 1+5 (gauge singlet) scalars, a neutrino mass matrix of a new type is speculated. The mass matrix is described…

High Energy Physics - Phenomenology · Physics 2009-11-13 Yoshio Koide

The gauge interactions of any supersymmetric extension of the standard model involve new flavor mixing matrices. The assumptions involved in the construction of minimal supersymmetric models, both $SU(3) \times SU(2) \times U(1)$ and grand…

High Energy Physics - Phenomenology · Physics 2009-10-28 Nima Arkani-Hamed , Hsin-Chia Cheng , L. J. Hall

We investigate a model that the Yukawa coupling form is constructed by two kinds of matrix (M_0 and M_1). For example, in the SO(10) GUT model, M_0 and M_1 are Yukawa couplings generated by the 10 and 126 Higgs scalars. We study how this…

High Energy Physics - Phenomenology · Physics 2009-11-10 K. Matsuda

We propose a new model of leptons and quarks based on the discrete flavor symmetry $T'$, the double covering of $A_4$, in which the hierarchies of charged fermion masses and the mildness of neutrino masses are responsible for Higgs scalars.…

High Energy Physics - Phenomenology · Physics 2013-07-17 Y. H. Ahn

In the context of the 2HDM, and assuming that neutrinos acquire masses via the Weinberg operator, we perform a systematic analysis to determine the minimal quark and lepton flavour patterns, compatible with masses, mixing and CP violation…

High Energy Physics - Phenomenology · Physics 2025-12-03 J. R. Rocha , H. B. Câmara , R. G. Felipe , F. R. Joaquim