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Related papers: A(4) Symmetry and Neutrinos

200 papers

The structure of the neutrino mixing matrix is indicative of an underlying family symmetry that interrelates the three generations of fermions in the Standard Model. We systematically scan the parameter space of 76 discrete non-Abelian…

High Energy Physics - Phenomenology · Physics 2011-11-01 Akin Wingerter , Krishna Mohan Parattu

In this talk I present my personal summary of the progress on the determination of the masses of the neutrinos and of the leptonic flavour mixing from the combined analysis of the experimental results.

High Energy Physics - Phenomenology · Physics 2019-02-14 M. C. Gonzalez-Garcia

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

We consider a model based on $A_4$ symmetry to explain the phenomenon of neutrino mixing. The spontaneous symmetry breaking of $A_4$ symmetry leads to a co-bimaximal mixing matrix at leading order. We consider the effect of higher order…

High Energy Physics - Phenomenology · Physics 2017-04-05 Sruthilaya M. , R. Mohanta

The observed quark hierarchies suggest a simple family symmetry. Generalized to leptons through grand-unified quantum numbers, it produces a neutrino mixing matrix with order-one \nu_{\mu} - \nu_{\tau} mixing, and order-\lambda^3 \nu_e -…

High Energy Physics - Phenomenology · Physics 2009-10-31 John K. Elwood , Nikolaos Irges , Pierre Ramond

We propose a unique lepton mixing scheme and its association with an exact hierarchy-philic neutrino mass matrix texture in the light of Type-I+Type-II seesaw mechanism under the framework of $A_4 \times Z_{10}$ discrete flavour symmetry.…

High Energy Physics - Phenomenology · Physics 2024-07-24 Manash Dey , Subhankar Roy

If neutrinos are Dirac, the conditions for cobimaximal mixing, i.e. $\theta_{23}=\pi/4$ and $\delta_{CP}=\pm \pi/2$ in the $3 \times 3$ neutrino mixing matrix, are derived. One example with $A_4$ symmetry and radiative Dirac neutrino masses…

High Energy Physics - Phenomenology · Physics 2021-04-07 Ernest Ma

Radiative Dirac neutrino masses and their mixing are linked to dark matter through the non-Abelian discrete symmetry $A_5$ of the 4-dimensional pentatope, softly broken to $A_4$ of the 3-dimensional tetrahedron. This unifying understanding…

High Energy Physics - Phenomenology · Physics 2022-04-20 Ernest Ma

It has recently been shown that the phenomenologically successful pattern of cobimaximal neutrino mixing ($\theta_{13} \neq 0$, $\theta_{23} = \pi/4$, and $\delta_{CP} = \pm \pi/2$) may be achieved in the context of the non-Abelian discrete…

High Energy Physics - Phenomenology · Physics 2018-01-17 Ernest Ma

Using the type II seesaw approach and properties of discrete flavor symmetry group representations, we build a supersymmetric $A_{4}\times A_{3}$\ neutrino model with $\theta_{13}\neq0$. After describing the basis of this model--which is…

High Energy Physics - Phenomenology · Physics 2016-06-22 R. Ahl Laamara , M. A Loualidi , E. H Saidi

Status of determination of the neutrino masses and mixing is formulated and possible uncertainties, especially due to presence of the sterile neutrinos, are discussed. The data hint an existence of special ``neutrino'' symmetries. If not…

High Energy Physics - Phenomenology · Physics 2009-11-11 Alexei Yu. Smirnov

Small discrete family symmetries such as S4, A4 or A5 may lead to simple leading-order predictions for the neutrino mixing matrix such as the bimaximal, tribimaximal or golden ratio mixing patterns, which may be brought into agreement with…

High Energy Physics - Phenomenology · Physics 2015-06-23 Peter Ballett , Stephen F. King , Christoph Luhn , Silvia Pascoli , Michael A. Schmidt

A group-theoretical connection between horizontal symmetry $\G$ and fermion mixing is established, and applied to neutrino mixing. The group-theoretical approach is consistent with a dynamical theory based on $U(1)\times \G$, but the…

High Energy Physics - Phenomenology · Physics 2011-05-27 C. S. Lam

The A4 x U(1) flavor model of He, Keum, and Volkas is extended to provide a minimal modification to tribimaximal mixing that accommodates a nonzero reactor angle theta13 ~ 0.1. The sequestering problem is circumvented by forbidding…

High Energy Physics - Phenomenology · Physics 2013-01-15 Yoni BenTov , Xiao-Gang He , A. Zee

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

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

Two new neutrino mass matrix textures exhibiting the \emph{mixed $\mu$-$\tau$ symmetry} are proposed. The mass matrices hint for a promising neutrino mixing schemes and find their connections with $\Delta(27)$ and $A_{4}$ discrete symmetry…

High Energy Physics - Phenomenology · Physics 2023-06-14 Pralay Chakraborty , Subhankar Roy

We construct phenomenologically viable models of lepton masses and mixing based on modular $A_4$ invariance broken to residual symmetries $\mathbb{Z}^{T}_3$ or $\mathbb{Z}^{ST}_3$ and $\mathbb{Z}^S_2$ respectively in the charged lepton and…

High Energy Physics - Phenomenology · Physics 2019-05-22 P. P. Novichkov , S. T. Petcov , M. Tanimoto

Over the last ten years tri-bimaximal mixing has played an important role in modeling the flavour problem. We give a short review of the status of flavour symmetry models of neutrino mixing. We concentrate on non-Abelian discrete…

High Energy Physics - Phenomenology · Physics 2015-06-05 S. Morisi , J. W. F. Valle

Tribimaximal leptonic mixing is a mass-independent mixing scheme consistent with the present solar and atmospheric neutrino data. By conveniently decomposing the effective neutrino mass matrix associated to it, we derive generic predictions…

High Energy Physics - Phenomenology · Physics 2011-03-09 I. de Medeiros Varzielas , R. Gonzalez Felipe , H. Serodio