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Related papers: An A_5 Model of Four Lepton Generations

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We propose a renormalisable model based on $A_4$ family symmetry with an $SU(5)$ grand unified theory (GUT) which leads to the minimal supersymmetric standard model (MSSM) with a two right-handed neutrino seesaw mechanism. Discrete…

High Energy Physics - Phenomenology · Physics 2015-07-01 Fredrik Björkeroth , Francisco J. de Anda , Ivo de Medeiros Varzielas , Stephen F. King

We argue that the A_4 symmetry as required by three flavors of fermions may well-embed in the SU(3)_C X SU(3)_L X U(1)_X gauge model. The new neutral fermion singlets as introduced in a canonical seesaw mechanism can be combined with the…

High Energy Physics - Phenomenology · Physics 2015-03-13 P. V. Dong , L. T. Hue , H. N. Long , D. V. Soa

We present an $S_4$ flavor model to unify quarks and leptons in the framework of the SU(5) GUT. Three generations of $\bar 5$-plets in SU(5) are assigned $3_1$ of $S_4$ while the first and the second generations of 10-plets in SU(5) are…

High Energy Physics - Phenomenology · Physics 2010-01-15 Hajime Ishimori , Yusuke Shimizu , Morimitsu Tanimoto

We study a three-loop induced neutrino mass scenario from a non-holomorphic modular $A_4$ flavor symmetry and reach the minimum scenario leading predictions of the lepton masses, mixing angles, and Dirac and Majorana phases, which are shown…

High Energy Physics - Phenomenology · Physics 2025-12-04 Takaaki Nomura , Hiroshi Okada

We consider the neutrino physics of models with a sequentially broken U(2) flavor symmetry. Such theories yield the observed pattern of quark and lepton masses, while maintaining sufficient degeneracies between superparticles of the first…

High Energy Physics - Phenomenology · Physics 2014-11-17 Christopher D. Carone , Lawrence J. Hall

We propose a simple model to simultaneously explain four observed flavor anomalies while generating the neutrino mass at the one-loop level. Specifically, we address the measured anomalous magnetic dipole moments of the muon, $\Delta a_\mu$…

High Energy Physics - Phenomenology · Physics 2021-09-13 We-Fu Chang

In this paper we study an SU(5) x A5 flavour model which exhibits a neutrino mass sum rule and golden ratio mixing in the neutrino sector which is corrected from the charged lepton Yukawa couplings. We give the full renormalizable…

High Energy Physics - Phenomenology · Physics 2014-12-15 Julia Gehrlein , Jens P. Oppermann , Daniela Schäfer , Martin Spinrath

We study a second CP symmetry compatible with the $A_4$ flavor group, which interchanges the representations $\mathbf{1}'$ and $\mathbf{1}"$. We analyze the lepton mixing patterns arising from the $A_4$ and CP symmetry broken to residual…

High Energy Physics - Phenomenology · Physics 2016-11-23 Cai-Chang Li , Jun-Nan Lu , Gui-Jun Ding

We analyse in detail the phenomenological implications for lepton masses and mixing derived by the breaking of the discrete symmetries $A_5 \times CP$ into the subgroups $Z_2 \times CP$ in the neutrino sector and $Z_5$ in the charged lepton…

High Energy Physics - Phenomenology · Physics 2020-01-08 Andrea Di Iura , M. L. López-Ibáñez , Davide Meloni

We propose a spontaneous A_4 flavour symmetry breaking scheme to understand the observed pattern of quark and neutrino mixing. The fermion mass eigenvalues are arbitrary, but the mixing angles are constrained in such a way that the overall…

High Energy Physics - Phenomenology · Physics 2010-04-06 Xiao-Gang He , Yong-Yeon Keum , Raymond R. Volkas

The neutrino oscillation data are well explained by the tri-bimaximal pattern. Recently a paper appeared showing that also the bimaximal pattern could be a very good starting point in order to describe the lepton mixing. In this paper I…

High Energy Physics - Phenomenology · Physics 2015-05-14 Luca Merlo

Very little is known about the mass spectrum of fermions in the standard model. In this talk, I point out that in the simplest extension of the standard model, in which all right-handed fields are singlets, it is quite possible that a…

High Energy Physics - Phenomenology · Physics 2007-05-23 Marc Sher

Tribimaximal lepton mixing can be obtained assuming A4 flavour symmetry. Many possibilities have been explored in the literature and we give a classification in terms of A4 representations. We propose some phenomenological and theoretical…

High Energy Physics - Phenomenology · Physics 2010-11-11 S. Morisi

Recent T2K results indicate a sizeable reactor angle theta_13 which would rule out exact tri-bimaximal lepton mixing. We study the vacuum alignment of the Altarelli-Feruglio A4 family symmetry model including additional flavons in the 1'…

High Energy Physics - Phenomenology · Physics 2011-09-13 Stephen F. King , Christoph Luhn

We speculate that the mass spectrum of three neutrinos might have a normal hierarchy as that of three charged leptons or that of three up-type (or down-type) quarks. In this spirit, we propose a novel parametrization of the $3\times 3$…

High Energy Physics - Phenomenology · Physics 2009-11-11 Harald Fritzsch , Zhi-zhong Xing

We present the lepton flavor model with $\Delta (54)$, which appears typically in heterotic string models on the $T^2/Z_3$ orbifold. Our model reproduces the tri-bimaximal mixing in the parameter region around degenerate neutrino masses or…

High Energy Physics - Phenomenology · Physics 2010-04-30 Hajime Ishimori , Tatsuo Kobayashi , Hiroshi Okada , Yusuke Shimizu , Morimitsu Tanimoto

We investigate the texture structures of lepton mass matrices with four (five) non-zero elements in the charged lepton mass matrix and three (four) vanishing cofactors in the neutrino mass matrix. Using weak basis transformations, all…

High Energy Physics - Phenomenology · Physics 2017-11-28 S. Dev , Desh Raj , Radha Raman Gautam

We study neutrino masses and mixing in the context of flavor models with A4 symmetry, three scalar doublets in the triplet representation, and three lepton families. We show that there is no representation assignment that yields a…

High Energy Physics - Phenomenology · Physics 2013-09-10 R. Gonzalez Felipe , H. Serodio , Joao P. Silva

Given the absence of a definitive top-down indication for understanding the peculiar structure of the lepton sector, discrete flavor symmetries offer a profound perspective for examining the intricate patterns of lepton masses and mixings.…

High Energy Physics - Phenomenology · Physics 2024-12-03 Ajdin Palavrić

We construct a supersymmeterized version of the model presented by Grimus and Lavoura (GL) in [1] which predicts theta_{23} maximal and theta_{13}=0 in the lepton sector. For this purpose, we extend the flavor group, which is D4 x…

High Energy Physics - Phenomenology · Physics 2010-04-14 A. Adulpravitchai , A. Blum , C. Hagedorn