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Related papers: Two A4 modular symmetries for Tri-Maximal 2 mixing

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We perform a comprehensive study of the homogeneous finite modular group $A'_5$ which is the double covering of $A_5$. The integral weight and level 5 modular forms have been constructed up to weight 6 and they are decomposed into the…

High Energy Physics - Phenomenology · Physics 2021-05-26 Chang-Yuan Yao , Xiang-Gan Liu , Gui-Jun Ding

The tri-bimaximal mixing matrix is most likely the leading order term in the description of leptonic mixing. We derive deviations from tri-bimaximal mixing(TBM) due to corrections from the charged lepton sector. We assume a decoupled 2-3…

High Energy Physics - Phenomenology · Physics 2008-09-17 Alakabha Datta

The flavor structure of quarks and leptons and quark-lepton unification are studied in the framework of Pati-Salam models with $A_4$ modular symmetry. The three generations of the left-handed and right-handed fermions are assigned to be…

High Energy Physics - Phenomenology · Physics 2024-04-11 Gui-Jun Ding , Si-Yi Jiang , Stephen F. King , Jun-Nan Lu , Bu-Yao Qu

We determine the symmetry groups under which the charged-lepton and the Majorana-neutrino mass terms are invariant. We note that those two groups always exist trivially, i.e. independently of the presence of any symmetries in the…

High Energy Physics - Phenomenology · Physics 2009-10-02 W. Grimus , L. Lavoura , P. O. Ludl

We perform a systematical analysis of the $A_4$ modular models with generalized CP for the masses and flavor mixing of quarks and leptons, and the most general form of the quark and lepton mass matrices is given. The CP invariance requires…

High Energy Physics - Phenomenology · Physics 2021-06-02 Chang-Yuan Yao , Jun-Nan Lu , Gui-Jun Ding

We propose a non-holomorphic modular $A_4$ model under the assumption of universal couplings. In this framework, a charged lepton mass hierarchy is not created through parameter fine tuning or hierarchical Yukawa couplings, but instead is…

High Energy Physics - Phenomenology · Physics 2026-04-20 Mohammed Abbas

We present a supersymmetric model with the flavour symmetry S4 x Z3 and a CP symmetry which are broken to a Z3 subgroup of the flavour symmetry in the charged lepton sector and to Z2 x CP (x Z3) in the neutrino one at leading order. This…

High Energy Physics - Phenomenology · Physics 2014-02-18 Ferruccio Feruglio , Claudia Hagedorn , Robert Ziegler

Recently, many authors showed that if the solar and atmospheric neutrino data are both described by maximal mixing vacuum oscillations at the relevant mass scale, then there exists a unique bi-maximal lepton mixing matrix for three neutrino…

High Energy Physics - Phenomenology · Physics 2009-12-30 Sin Kyu Kang , C. S. Kim

The confirmation of the discrepancy with the Standard Model predictions in the anomalous magnetic moment by the Muon g-2 experiment at Fermilab points to a low scale of new physics. Flavour symmetries broken at low energies can account for…

High Energy Physics - Phenomenology · Physics 2021-11-10 Lorenzo Calibbi , M. L. López-Ibáñez , Aurora Melis , Oscar Vives

The Non-Abelian finite group PSL_2(7) is the only simple subgroup of SU(3) with a complex three-dimensional irreducible representation. It has two maximal subgroups, S_4 which, along with its own A_4 subgroup, has been successfully applied…

High Energy Physics - Phenomenology · Physics 2008-11-26 Christoph Luhn , Salah Nasri , Pierre Ramond

Effective Flavour Models do not address questions related to the nature of the fundamental renormalisable theory at high energies. We study the ultraviolet completion of Flavour Models, which in general has the advantage of improving the…

High Energy Physics - Phenomenology · Physics 2011-03-18 Ivo de Medeiros Varzielas , Luca Merlo

A multiplicity of quark-lepton families can naturally arise as zero-modes in flux compactifications. The flavour structure of quark and lepton mass matrices is then determined by the wave function profiles of the zero-modes. We consider a…

High Energy Physics - Phenomenology · Physics 2017-04-26 Wilfried Buchmuller , Julian Schweizer

We propose a lepton seesaw model to get the same mass-origin of charged-leptons and neutrinos introducing a modular $A_4$ symmetry. In this scenario, the mass matrix of charged-leptons is induced via seesaw-like mechanism while the mass…

High Energy Physics - Phenomenology · Physics 2026-04-02 Takaaki Nomura , Hiroshi Okada

We perform an exhaustive analysis of all possible breaking patterns arising from $S_4\rtimes H_{CP}$ in a new {\it tri-direct CP approach} to the minimal seesaw model with two right-handed neutrinos, and construct a realistic flavour model…

High Energy Physics - Phenomenology · Physics 2019-05-08 Gui-Jun Ding , Stephen F. King , Cai-Chang Li

The absence of direct evidence for new physics at current collider energies motivates the study of indirect effects within the framework of the Standard Model Effective Field Theory (SMEFT). In this work, we investigate the role of the…

High Energy Physics - Phenomenology · Physics 2025-05-06 Adrián Moreno-Sánchez , Ajdin Palavrić

We study $SU(4)_C \times SU(2)_L \times U(1)_R$ models with modular $A_4$ symmetry that provide unified description of the quark and lepton sector including the flavor structures. The models are distinguished by the assignments of the…

High Energy Physics - Phenomenology · Physics 2023-01-18 Takaaki Nomura , Hiroshi Okada , Yutaro Shoji

We study one-loop induced radiative seesaw model applying a modular $A_4$ flavor symmetry, in which the neutrino mass matrix is achieved by two different Yukawa couplings one of which also contributes to positive value of muon anomalous…

High Energy Physics - Phenomenology · Physics 2019-08-01 Hiroshi Okada , Yuta Orikasa

We discuss our recently proposed S3(down)xS3(up) flavour-permutation-symmetric mixing observables, giving expressions for them in terms of (moduli-squared) of the mixing matrix elements. We outline their successful use in providing…

High Energy Physics - Phenomenology · Physics 2008-05-23 P. F. Harrison , D. R. J. Roythorne , W. G. Scott

We develop a bottom-up approach to flavour models which combine modular symmetry with orbifold constructions. We first consider a 6d orbifold $\mathbb{T}^2/\mathbb{Z}_N$, with a single torus defined by one complex coordinate $z$ and a…

High Energy Physics - Phenomenology · Physics 2023-07-12 Francisco J. de Anda , Stephen F. King

We propose a lepton model under modular $A_4$ and gauged $U(1)_R$ symmetries, in which the neutrino masses are induced at one-loop level. Thanks to the modular $A_4$ symmetry, we have several predictions on the lepton sector, especially, on…

High Energy Physics - Phenomenology · Physics 2020-10-08 Keiko I. Nagao , Hiroshi Okada