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Related papers: A new A4 model for lepton mixing

200 papers

We study an extension of the standard model based on the flavor symmetry A4 only. Neutrino Majorana mass terms arise from dimension five operator and charged lepton masses from renormalizable Yukawa couplings. We introduce three Higgs…

High Energy Physics - Phenomenology · Physics 2010-01-07 S. Morisi , E. Peinado

A generalized CP symmetry for leptons is presented where CP transformations are part of an $S_4$ symmetry that connects different families. We study its implications for lepton mixings in a gauge model realization of the idea using type II…

High Energy Physics - Phenomenology · Physics 2012-10-17 R. N. Mohapatra , C. C. Nishi

Some properties of lepton mixing and neutrino masses can be computed under the assumption of A5 and CP as a symmetry in the leptonic sector. The results show that four mixing patterns accommodate well the oscillation data, i.e. all the…

High Energy Physics - Phenomenology · Physics 2016-04-29 Andrea Di Iura

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 recent discovery of a non-zero value of the mixing angle theta_13 has ruled out tri-bimaximal mixing as the correct lepton mixing pattern generated by some discrete flavor symmetry (barring large next-to-leading order corrections in…

High Energy Physics - Phenomenology · Physics 2013-04-03 Martin Holthausen , Kher Sham Lim , Manfred Lindner

We perform a systematic search for simple but viable lepton mixing patterns. Our main criterion is that the mixing matrix can be parameterized by three rotation angles, which are simple fractions of pi. These simple rotation angles possess…

High Energy Physics - Phenomenology · Physics 2015-05-28 Werner Rodejohann , He Zhang , Shun Zhou

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

Discrete flavour groups have been studied in connection with special patterns of neutrino mixing suggested by the data, such as Tri-Bimaximal mixing (groups A4, S4...) or Bi-Maximal mixing (group S4...) etc. We review the predictions for…

High Energy Physics - Phenomenology · Physics 2015-06-05 Guido Altarelli , Ferruccio Feruglio , Luca Merlo , Emmanuel Stamou

We provide an $A_4$ based flavor symmetric scenario to accommodate the inverse seesaw mechanism for explaining light neutrino masses and mixing. We find that the lepton mixing, in particular the tri-bimaximal mixing pattern and its…

High Energy Physics - Phenomenology · Physics 2017-08-07 Biswajit Karmakar , Arunansu Sil

We revisit the $A_4$ model for leptons in light of new result of NuFIT 3.2. We introduce a new flavon $\eta$ transforming as $A_4$ singlet $1'$ or $1"$ which couples to both charged leptons and neutrinos in next-leading order operators. The…

High Energy Physics - Phenomenology · Physics 2019-12-06 Sin Kyu Kang , Yusuke Shimizu , Kenta Takagi , Shunya Takahashi , Morimitsu Tanimoto

We propose a simple non-supersymmetric lepton flavor model with $A_4$ symmetry. The $A_4$ group is a minimal one which includes triplet irreducible representation. We introduce three Higgs doublets which are assigned as triplet of the $A_4$…

High Energy Physics - Phenomenology · Physics 2023-06-28 Yukimura Izawa , Yusuke Shimizu , Hironori Takei

We discuss a minimal lepton flavour model with two modular $A_4$ symmetries, one acting on neutrinos and the other acting on charged leptons. Two corresponding moduli fields are restricted at stabilisers. To avoid vanishing or degenerate…

High Energy Physics - Phenomenology · Physics 2024-03-07 Han Zhang , Ye-Ling Zhou

We present a model for leptonic mixing and the lepton masses based on flavor symmetries and higher-dimensional mass operators. The model predicts bilarge leptonic mixing (i.e., the mixing angles theta_{12} and theta_{23} are large and the…

High Energy Physics - Phenomenology · Physics 2009-11-07 Tommy Ohlsson , Gerhart Seidl

We suggest a low-scale model based on $A_4\times Z_4 \times Z_2$ symmetry and a global lepton number $U(1)_L$ symmetry capable of generating the current neutrino data. The neutrino mass smallness is reproduced by the linear seesaw…

High Energy Physics - Phenomenology · Physics 2023-02-08 V. V. Vien , H. N. Long

We present a model based on an O(3) flavor symmetry and a minimal extension of the scalar sector to induce hierarchical breaking, O(3) -> O(2) -> SO(2) -> nothing. The model naturally accounts for all the known lepton parameters and yields…

High Energy Physics - Phenomenology · Physics 2009-10-31 Gilad Perez

Assuming three generations of Majorana neutrinos, we study the different mixing patterns that arise from the non-trivial breaking of the flavor group A5 and CP to the residual symmetries Z3, Z5 or Z2 x Z2 in the charged lepton and to Z2 x…

High Energy Physics - Phenomenology · Physics 2015-09-30 Andrea Di Iura , Claudia Hagedorn , Davide Meloni

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

The Daya Bay Collaboration has recently observed neutrino oscillations in the nu_e-bar -> nu_e-bar disappearance channel, indicating that sin^2 theta_13 = 0.024 +(-) 0.005 (1 sigma) and theta_13 = 0 is already excluded at the 5.2 sigma…

High Energy Physics - Phenomenology · Physics 2012-05-04 Shun Zhou

Discrete non-Abelian Symmetries have been extensively used to reproduce the lepton mixings. In particular, the S4 group turned out to be suitable to describe predictive mixing patterns, such as the well-known Tri-Bimaximal and the Bimaximal…

High Energy Physics - Phenomenology · Physics 2015-06-05 Federica Bazzocchi , Luca Merlo

We revisit $A_4$ flavor symmetry for the lepton sector with minimal Higgs sector, namely just one $A_4-$triplet SU(2)-doublet scalar. To increase predictivity even further, we impose the constraint of renormalizability. A geometric…

High Energy Physics - Phenomenology · Physics 2008-10-30 Paul H. Frampton , Shinya Matsuzaki