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Related papers: Neutrino Mixing: $A_4$ Variations

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Discrete non-abelian flavor symmetries give in a natural way tri-bimaximal (TBM) mixing as showed in a prototype model. However neutrino mass matrix pattern may be very different from the tri-bimaximal one if small deviations of TBM will be…

High Energy Physics - Phenomenology · Physics 2015-05-20 S. Morisi

We present a see-saw $A_4$ model for Tri-Bimaximal mixing which is based on a very economical flavour symmetry and field content and still possesses all the good features of $A_4$ models. In particular the charged lepton mass hierarchies…

High Energy Physics - Phenomenology · Physics 2009-08-20 Guido Altarelli , Davide Meloni

We explore the possibility of generating a non-zero $U_{e3}$ element of the neutrino mixing matrix from tribimaximal neutrino mixing by adding a light sterile neutrino to the active neutrinos. Small active-sterile mixing can provide the…

High Energy Physics - Phenomenology · Physics 2016-10-11 S. Dev , Desh Raj , Radha Raman Gautam

This work proposes two models of neutrino masses that predict non-zero $\theta_{13}$ under the non-Abelian discrete flavor symmetry $\mathbb{S}_3\otimes\mathbb{Z}_2$. We advocate that the size of $\theta_{13}$ is understood as a group…

High Energy Physics - Phenomenology · Physics 2012-08-14 Kim Siyeon

The observed neutrino mixing, having a near maximal atmospheric neutrino mixing angle and a large solar mixing angle, is close to tri-bi-maximal. We argue that this structure suggests a family symmetric origin in which the magnitude of the…

High Energy Physics - Phenomenology · Physics 2008-11-26 I. de Medeiros Varzielas , S. F. King , G. G. Ross

The present article is an endeavor to look into some fruitful frameworks based on "Bi-maximal" neutrino mixing, from a model independent stand. The possibilities involving the correction or attenuation of the original BM mixing matrix,…

High Energy Physics - Phenomenology · Physics 2016-03-28 Subhankar Roy , N. Nimai Singh

In this work, a flavour theory of a neutrino mass model based on $ A_{4} $ symmetry is considered to explain the phenomenology of neutrino mixing. The spontaneous symmetry breaking of $ A_{4} $ symmetry in this model leads to tribimaximal…

High Energy Physics - Phenomenology · Physics 2022-04-05 Gayatri Ghosh

We study a neutrino mass model with $A_4$ discrete flavor symmetry using a type-I seesaw mechanism. The inclusion of extra flavons in our model leads to the deviations from exact tribimaximal mixing pattern resulting in a nonzero…

High Energy Physics - Phenomenology · Physics 2023-07-10 Animesh Barman , Ng. K. Francis , Hrishi Bora

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

In light of the observation of a relatively large $\theta_{13}$, the ever popular Tri-Bimaximal (TBM) neutrino mixing which predicts a vanishing $\theta_{13}$ needs modifications. In this paper, we shall discuss the possibility of modifying…

High Energy Physics - Phenomenology · Physics 2015-06-19 Zhen-hua Zhao

The addition of an A_4 family symmetry and extended Higgs sector to the Standard Model can generate the tribimaximal mixing pattern for leptons, assuming the correct vacuum expectation value alignment of the Higgs scalars. Deviating this…

High Energy Physics - Phenomenology · Physics 2014-11-20 James Barry , Werner Rodejohann

We show that the A4 discrete symmetry that naturally leads to tri-bimaximal neutrino mixing can be simply obtained as a result of an orbifolding starting from a model in 6 dimensions. This particular orbifolding has four fixed points where…

High Energy Physics - Phenomenology · Physics 2010-04-06 Guido Altarelli , Ferruccio Feruglio , Yin Lin

The neutrino mixing matrix has been measured to be of a form consistent with tribimaximal mixing, while the quark mixing matrix is almost diagonal. A scheme based on flavour A_4 symmetry for understanding these patterns simultaneously is…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. R. Volkas

A new theoretical insight into the pattern of neutrino mixing and leptonic $CP$ violation is presented. It leads naturally and uniquely to a specific dark sector of three real neutral scalar singlets, with the radiative implementation of…

High Energy Physics - Phenomenology · Physics 2015-09-09 Ernest Ma

The long baseline neutrino experiment, T2K, and the reactor experiment, Double Chooz will soon present new data. If we expect $\sin\theta_{13}$ to be 0.1-0.2, which is close to the present experimental upper bound, we should not persist in…

High Energy Physics - Phenomenology · Physics 2011-08-30 Yusuke Shimizu , Morimitsu Tanimoto , Atsushi Watanabe

We present a model based on the A4 non-abelian discrete symmetry leading to a predictive five-parameter neutrino mass matrix and providing a stable dark matter candidate. We found an interesting correlation among the atmospheric and the…

High Energy Physics - Phenomenology · Physics 2011-04-20 D. Meloni , S. Morisi , E. Peinado

We formulate and discuss a 4-dimensional SUSY version of an A4 model for tri-bimaximal neutrino mixing which is completely natural. We also study the next-to-the-leading corrections and show that they are small, once the ratios of A4…

High Energy Physics - Phenomenology · Physics 2008-11-26 Guido Altarelli , Ferruccio Feruglio

The nonzero and relatively large $\theta_{13}$ have been reported by Daya Bay, T2K, MINOS, and Double Chooz Collaborations. In order to accommodate the nonzero $\theta_{13}$, we modified the tribimaximal (TB), bimaxima (BM), and democratic…

High Energy Physics - Phenomenology · Physics 2012-07-02 Asan Damanik

I review the construction of a model for lepton masses based on the flavour symmetry group A4 x U(1) reproducing the so-called tri-bimaximal lepton mixing scheme, in eccelent agreement with current data. The model predicts a neutrino…

High Energy Physics - Phenomenology · Physics 2009-04-25 Ferruccio Feruglio

The cubic symmetry S_4 contains A_4 and S_3, both of which have been used to study neutrino mass matrices. Using S_4 as the family symmetry of a complete supersymmetric theory of leptons, it is shown how the requirement of breaking S_4 at…

High Energy Physics - Phenomenology · Physics 2009-11-11 Ernest Ma