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Related papers: A new A4 model for lepton mixing

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Neutrino oscillation experiments have confirmed that neutrinos are massive particles and lepton flavors are mixed. To explain the observed lepton mass spectra and flavor mixing patterns, flavor symmetry plays a crucial and unique role. In…

High Energy Physics - Phenomenology · Physics 2025-12-10 Chang-Qi Hu , Chun-Yuan Li , Xiao Liang , Xing-Hua Yang , Dai-Xing Zhang

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

We study a double covering of modular $A_4$ flavor symmetry in which we construct lepton models in cases of canonical seesaw and radiative seesaw models. Through $\chi$ square numerical analysis, we show some predictions for the cases,…

High Energy Physics - Phenomenology · Physics 2022-12-07 Hiroshi Okada , Yuta Orikasa

We furnish a supersymmetric extension of the Standard Model with a flavour discrete symmetry $A_5$ under which the lepton fields transform as an irreducible triplet. Additional (`flavon') superfields are used to break $A_5$ into a…

High Energy Physics - Phenomenology · Physics 2015-06-18 I. de Medeiros Varzielas , L. Lavoura

It has been recently claimed that the symmetry group S4 yields to the Tri-bimaximal neutrino mixing in a "natural" way from the group theory point of view. Approving of this feature as an indication, we build a supersymmetric model of…

High Energy Physics - Phenomenology · Physics 2010-05-12 Federica Bazzocchi , Luca Merlo , Stefano Morisi

Current experimental data on the neutrino parameters is in good agreement with tribimaximal mixing and may indicate the presence of an underlying family symmetry. For 76 flavor groups, we perform a systematic scan for models: The particle…

High Energy Physics - Phenomenology · Physics 2011-08-11 Krishna Mohan Parattu , Akin Wingerter

In the three-Higgs doublet model (3HDM) frame, we search for discrete flavour symmetries that give relations among the lepton masses and their mixing angles. We explore discreet non-Abelian groups of order less than 1035, treating neutrinos…

High Energy Physics - Phenomenology · Physics 2023-09-18 Joris Vergeest , Marek Zrałek , Bartosz Dziewit , Piotr Chaber

Including the generalized CP symmetry, we have performed a comprehensive scan of leptonic mixing patterns which can be obtained from finite discrete groups with order less than 2000. Both the semidirect approach and its variant are…

High Energy Physics - Phenomenology · Physics 2016-11-02 Chang-Yuan Yao , Gui-Jun Ding

In this paper, we present a systematic investigation on simple inverse seesaw models for neutrino masses and flavor mixing based on the modular $S^{}_4$ symmetry. Two right-handed neutrinos and three extra fermion singlets are introduced to…

High Energy Physics - Phenomenology · Physics 2021-10-01 Xinyi Zhang , Shun Zhou

We propose and discuss a new Littlest Seesaw model, realised in the tri-direct CP approach, in which the couplings of the two right-handed neutrinos to the lepton doublets are proportional to $(0,-1,1)$ and $(1,5/2,-1/2)$ respectively with…

High Energy Physics - Phenomenology · Physics 2020-06-24 Ping-Tao Chen , Gui-Jun Ding , Stephen F. King , Cai-Chang Li

We propose a flavour model based on an $A_4$ symmetry combined with a type-II seesaw mechanism for neutrino mass generation. The resulting neutrino mass matrix obeys a sum rule that, together with the measured mass-squared differences,…

High Energy Physics - Phenomenology · Physics 2026-03-16 Salvador Centelles Chuliá , Ranjeet Kumar

We construct two flavor models based on $S_4$ family symmetry and generalised CP symmetry. In both models, the $S_4$ family symmetry is broken down to the $Z^{SU}_2$ subgroup in the neutrino sector, as a consequence, the trimaximal…

High Energy Physics - Phenomenology · Physics 2014-02-19 Cai-Chang Li , Gui-Jun Ding

Realistic quark masses and mixing angles are obtained applying the successful $A_4$ family symmetry for leptons, motivated by the quark-lepton assignments of SU(5). The $A_4$ symmetry is suitable to give tri-bimaximal neutrino mixing matrix…

High Energy Physics - Phenomenology · Physics 2008-11-26 H. Sawanaka

In the light of recent discovery of nonzero $\theta_{13}$, we have analyzed the Altarelli-Feruglio $A_4$ flavor symmetry model extended with additional flavon. The inclusion of the new field leads to the deviation from exact tri-bimaximal…

High Energy Physics - Phenomenology · Physics 2015-06-22 Biswajit Karmakar , Arunansu Sil

Following the newly formulated notion of form invariance of the neutrino mass matrix, a complete model of leptons is constructed. It is based on a specific unitary 3 X 3 matrix U in family space, such that U^2 is the simple discrete…

High Energy Physics - Phenomenology · Physics 2009-11-10 Ernest Ma , G. Rajasekaran

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 a flavor model with $A_4$ symmetry which originates from $S_4$ modular group. In $S_4$ symmetry, $Z_2$ subgroup can be anomalous, and then $S_4$ can be violated to $A_4$. Starting with a $S_4$ symmetric Lagrangian at the tree…

High Energy Physics - Phenomenology · Physics 2020-03-18 Tatsuo Kobayashi , Yusuke Shimizu , Kenta Takagi , Morimitsu Tanimoto , Takuya H. Tatsuishi

We address two fundamental aspects of flavor physics: the mass hierarchy and the large lepton mixing angles. On one side, left-right flavor symmetry realizes the democratic mass matrix patterns and explains why one family is much heavier…

High Energy Physics - Phenomenology · Physics 2008-11-26 Federica Bazzocchi , Stefano Morisi , Marco Picariello

Contrary to the quark mixing matrix, the lepton mixing matrix could be symmetric. We study the phenomenological consequences of this possibility. In particular, we find that symmetry would imply that |U_{e3}| is larger than 0.16, i.e.,…

High Energy Physics - Phenomenology · Physics 2008-11-26 Kathrin A. Hochmuth , Werner Rodejohann

We present a systematic group space scan of discrete Abelian flavor symmetries for lepton mass models that produce nearly tribimaximal lepton mixing. In our models, small neutrino masses are generated by the type-I seesaw mechanism. The…

High Energy Physics - Phenomenology · Physics 2008-11-26 Florian Plentinger , Gerhart Seidl , Walter Winter