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Related papers: Non-Abelian Discrete Symmetries and Neutrino Masse…

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In this talk, I have reviewed few recent models on neutrino masses and mixing. Particularly, I have emphasised on $A_4$ symmetric models.

High Energy Physics - Phenomenology · Physics 2007-05-23 Ambar Ghosal

In the context of the non-Abelian discrete symmetry $A_4$, the neutrino mass matrix has been studied extensively. A brief update is presented to focus on the conceptual shift from tribimaximal mixing ($\theta_{13} = 0$, $\theta_{23} =…

High Energy Physics - Phenomenology · Physics 2015-12-02 Ernest Ma

The discrete non-Abelian symmetry $A_4$, valid at some high-energy scale, naturally leads to degenerate neutrino masses, without spoiling the hierarchy of charged-lepton masses. Realistic neutrino mass splittings and mixing angles (one of…

High Energy Physics - Phenomenology · Physics 2009-09-17 K. S. Babu , Ernest Ma , J. W. F. Valle

We review the application of non abelian discrete groups to the theory of neutrino masses and mixing, which is strongly suggested by the agreement of the Tri-Bimaximal mixing pattern with experiment. After summarizing the motivation and the…

High Energy Physics - Phenomenology · Physics 2015-05-18 Guido Altarelli , Ferruccio Feruglio

Recent progress is reviewed regarding the application of the non-Abelian symmetries S_3, D_4, and A_4 to the understanding of family structure in leptons and quarks.

High Energy Physics - Phenomenology · Physics 2007-05-23 Ernest Ma

A new idea for neutrino mass was proposed recently, where its smallness is not due to the seesaw mechanism, i.e. not inversely proportional to some large mass scale. It comes from a one-loop mechanism with dark matter in the loop consisting…

High Energy Physics - Phenomenology · Physics 2013-06-06 Subhaditya Bhattacharya , Ernest Ma , Alexander Natale , Ahmed Rashed

We present some recent developments on model building for neutrino masses and mixings. In particular, we review tri-bimaximal neutrino mixing derived from discrete groups, notably A4. We discuss the problems encountered with extending the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Guido Altarelli

In a new application of the discrete non-Abelian symmetry A_4 using the canonical seesaw mechanism, a three-parameter form of the neutrino mass matrix is derived. It predicts the following mixing angles for neutrino oscillations:…

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

In view of the fact that the data on neutrino mixing are still compatible with a situation where Bimaximal mixing is valid in first approximation and it is then corrected by terms of order of the Cabibbo angle, we present examples where…

High Energy Physics - Phenomenology · Physics 2015-05-27 Luca Merlo

Recent neutrino experiments have made very significant progresses and our knowledge of neutrino masses and mixing has considerably improved. In a model independent Monte Carlo approach, we have examined a very large class of textures, in…

High Energy Physics - Phenomenology · Physics 2007-06-22 V. Antonelli , F. Caravaglios , R. Ferrari , M. Picariello

We present a concise review of models for neutrino masses and mixings with particular emphasis on recent developments and current problems. We discuss in detail attempts at reproducing approximate tri-bimaximal mixing starting from discrete…

High Energy Physics - Phenomenology · Physics 2007-11-02 Guido Altarelli

Abelian family symmetries provide a predictive framework for neutrino mass models. In seesaw models based on an abelian family symmetry, the structures of the Dirac and the Majorana matrices are derived from the symmetry, and the neutrino…

High Energy Physics - Phenomenology · Physics 2009-02-16 Stéphane Lavignac

Restrictions on the neutrino masses and lepton mixing are reviewed. Solar, atmospheric and relic neutrinos give the indications of existence of nonzero neutrino masses and mixing. The data pick up two regions of mixing angles which are or…

High Energy Physics - Phenomenology · Physics 2009-09-25 Alexei Yu. Smirnov

The hypothesis of an additional abelian symmetry acting in a different way on the three families of leptons leads to interesting predictions in the neutrino sector. Contrary to what happens in most seesaw models, the structures of the Dirac…

High Energy Physics - Phenomenology · Physics 2007-05-23 Stéphane Lavignac

We discuss neutrino mass and mixing models based on discrete flavor symmetries. These models can include a variety of new interactions and non-standard particles such as sterile neutrinos, scalar Higgs singlets and multiplets. We point at…

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 review pedagogically non-Abelian discrete groups, which play an important role in the particle physics. We show group-theoretical aspects for many concrete groups, such as representations, their tensor products. We explain how to derive,…

High Energy Physics - Theory · Physics 2015-03-13 Hajime Ishimori , Tatsuo Kobayashi , Hiroshi Ohki , Hiroshi Okada , Yusuke Shimizu , Morimitsu Tanimoto

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

Recent atmospheric and solar neutrino experiments suggest that neutrinos have small but nonzero masses. They further suggest that mass eigenvalues have certain degree of hierarchical structures, and also some mixing angles are near-maximal…

High Energy Physics - Phenomenology · Physics 2007-05-23 Kiwoon Choi

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
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