English
Related papers

Related papers: A new A4 model for lepton mixing

200 papers

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

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

The observation of charged lepton flavor non-conservation would be a clear signature of physics beyond the Standard Model. In particular, supersymmetric (SUSY) models introduce mixings in the sneutrino and the charged slepton sectors which…

High Energy Physics - Phenomenology · Physics 2009-11-07 J. I. Illana , M. Masip

We introduce a scenario of lepton mixing in holographic composite Higgs models based on non-abelian discrete symmetries of the form G_f=X x Z_N, broken to Z_2 x Z_2 x Z_N in the elementary sector and to Z_N^(D) in the composite sector with…

High Energy Physics - Phenomenology · Physics 2015-05-30 Claudia Hagedorn , Marco Serone

In the formalism of the non-supersymmetric modular invariance approach to the flavour problem the elements of the Yukawa coupling and fermion mass matrices are expressed in terms of polyharmonic Maa{\ss} modular forms of level $N$ in…

High Energy Physics - Phenomenology · Physics 2024-08-29 Gui-Jun Ding , Jun-Nan Lu , S. T. Petcov , Bu-Yao Qu

Lepton mixing patterns from the modular group $PSL_2(7)$ with generalised CP symmetries are studied. The residual symmetries in both charged leptons and neutrinos sector are $Z_{2}\times CP$. Seven types of mixing patterns at the $3\sigma$…

High Energy Physics - Phenomenology · Physics 2020-02-04 Shu-Jun Rong

Flavour symmetries have been used to constrain both quark and lepton mixing parameters. In particular, they can be used to completely fix the mixing angles. For the lepton sector, assuming that neutrinos are Majorana particles, we have…

High Energy Physics - Phenomenology · Physics 2014-10-16 Renato M. Fonseca , Walter Grimus

We provide a systematic and thorough exploration of lepton flavor models in which the solar mixing angle is related to the golden ratio. For scenarios in which the solar mixing angle is given by the inverse cotangent of the golden ratio, we…

High Energy Physics - Phenomenology · Physics 2012-01-10 Gui-Jun Ding , Lisa L. Everett , Alexander J. Stuart

In this paper, we realize the tri-bimaximal mixing in the lepton sector in the context of minimal seesaw in which only two right-handed neutrinos are introduced, with the discrete group $S4$ as the family symmetry. In order to constrain the…

High Energy Physics - Phenomenology · Physics 2011-11-10 Zhen-hua Zhao

The neutrino oscillation data find a good approximation in the so-called tri-bimaximal pattern. Recently a paper appeared showing that also the bimaximal pattern, which is already ruled out by the measurements, could be a very good starting…

High Energy Physics - Phenomenology · Physics 2010-02-11 Luca Merlo

We present a concise review of the recent important experimental developments on neutrino mixing (hints for sterile neutrinos, large $\theta_{13}$, possible non maximal $\theta_{23}$, approaching sensitivity on $\delta_{CP}$) and their…

High Energy Physics - Phenomenology · Physics 2022-03-02 Guido Altarelli

We present minimalist constructions for lepton masses and mixing based on flavour symmetry under the modular group $\Gamma_N$ of lowest level $N=2$. As opposed to the only existing model of $\Gamma_2\cong S_3$ formulated in a SUSY…

High Energy Physics - Phenomenology · Physics 2023-09-11 Davide Meloni , Matteo Parriciatu

The neutrino oscillation data are in very good agreement with the tribimaximal mixing pattern: \sin^2\theta_{23}=1/2, \sin^2\theta_{12}=1/3, and \sin^2\theta_{13}=0. Attempts to generate this pattern based on finite family symmetry groups…

High Energy Physics - Phenomenology · Physics 2010-11-11 K. S. Babu , S. Gabriel

We propose a model based on modular $A_4$ symmetry containing a dark matter candidate, realizing radiatively induced neutrino mass at one-loop level. One finds that stability of dark matter candidate can be assured by nonzero value of…

High Energy Physics - Phenomenology · Physics 2019-08-07 Takaaki Nomura , Hiroshi Okada

In the supersymmetric seesaw model of neutrino masses, augmented by the non-Abelian discrete tetrahedral symmetry A_4, a specific pattern of neutrino mixing is automatically generated if one of the three heavy singlet neutrino superfields…

High Energy Physics - Phenomenology · Physics 2010-04-06 Ernest Ma

We propose a new scenario in a radiative seesaw model based on A_4 flavor symmetry. In this model, we explore a possibility of linking non-zero \theta_{13} to dark matter. And we analyze the lepton sector to predict the observed neutrinos…

High Energy Physics - Phenomenology · Physics 2015-06-03 Y. H. Ahn , Hiroshi Okada

We study the implications of an approximate $U(2)^5$ flavor symmetry at the TeV scale, under the assumption of new physics predominantly coupled to the third-generation fermions, focusing on the breaking of the $U(2)_\ell$ subgroup…

High Energy Physics - Phenomenology · Physics 2025-11-21 Sebastiano Covone , Pol Morell , Arianna Tinari

The data on neutrino mixing are at present compatible with Tri-Bimaximal (TB) mixing. If one takes this indication seriously then the models that lead to TB mixing in first approximation are particularly interesting and A4 models are…

High Energy Physics - Phenomenology · Physics 2009-05-15 Guido Altarelli

We propose a model of quark and lepton mixing based on the tetrahedral A(4) family symmetry with quark-lepton unification via the tetra-colour Pati-Salam gauge group SU(4)_{PS}, together with SU(2)_L x U(1)_R. The "tetra-model" solves many…

High Energy Physics - Phenomenology · Physics 2015-06-17 Stephen F. King

Flavour symmetries of Froggatt-Nielsen type can naturally reconcile the large quark and charged lepton mass hierarchies and the small quark mixing angles with the observed small neutrino mass hierarchies and their large mixing angles. We…

High Energy Physics - Phenomenology · Physics 2012-03-19 Wilfried Buchmüller , Valerie Domcke , Kai Schmitz