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Related papers: CP violations in a predictive $A_4$ symmetry model

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Cyclic symmetry in the neutrino sector with the type-I seesaw mechanism in the mass basis of charged leptons and right chiral neutrinos ($N_{iR}$, $i=e,\mu,\tau$) generates two fold degenerate light neutrino and three fold degenerate heavy…

High Energy Physics - Phenomenology · Physics 2016-06-08 Biswajit Adhikary , Mainak Chakraborty , Ambar Ghosal

We consider the minimal seesaw model, the Standard Model extended by two right-handed neutrinos, for explaining the neutrino masses and mixing angles measured in oscillation experiments. When one of right-handed neutrinos is lighter than…

High Energy Physics - Phenomenology · Physics 2023-07-26 Takehiko Asaka , Hiroyuki Ishida , Kazuki Tanaka

We discuss the neutrino mass matrix based on the Occam's Razor approach in the framework of the seesaw mechanism. We impose four zeros in the Dirac neutrino mass matrix, which give the minimum number of parameters needed for the observed…

High Energy Physics - Phenomenology · Physics 2016-07-06 Yuya Kaneta , Yusuke Shimizu , Morimitsu Tanimoto , Tsutomu T. Yanagida

We suggest predictive scenarios for neutrino masses which provide a common origin for CP violation in early universe cosmology and in neutrino oscillations. Our setup is the seesaw mechanism in the context of MSSM with two quasi-degenerate…

High Energy Physics - Phenomenology · Physics 2008-12-24 K. S. Babu , Yanzhi Meng , Zurab Tavartkiladze

We propose an $A_4$ modular invariant flavor model of leptons, in which both CP and modular symmetries are broken spontaneously by the vacuum expectation value of the modulus $\tau$. The value of the modulus $\tau$ is restricted by the…

High Energy Physics - Phenomenology · Physics 2021-08-18 Hiroshi Okada , Yusuke Shimizu , Morimitsu Tanimoto , Takahiro Yoshida

To understand the mass spectra of charged lepton and neutrino $A_4$ symmetry has been proposed in addition with the Standard $SU(2)_L\times U(1)_Y$ model. We break $A_4$ symmetry softly and the deviation from the tri-bimaximal mixing arises…

High Energy Physics - Phenomenology · Physics 2008-11-26 Biswajit Adhikary , Ambar Ghosal

Heavy right handed neutrinos could not only explain the observed neutrino masses via the seesaw mechanism, but also generate the baryon asymmetry of the universe via leptogenesis due to their CP-violating interactions in the early universe.…

High Energy Physics - Phenomenology · Physics 2016-11-28 Marco Drewes , Bjorn Garbrecht , Dario Gueter , Juraj Klaric

Leptogenesis in a left-right symmetric model is investigated for all possible neutrino mass hierarchies. The predictions of the model for low energy parameters as measured in neutrinoless double beta decay and in oscillation experiments are…

High Energy Physics - Phenomenology · Physics 2010-04-05 Werner Rodejohann

Motivated by the fact that, in some realistic models combining SO(10) GUTs and flavour symmetries, it is not possible to achieve the required baryon asymmetry through the CP asymmetry generated in the decay of right-handed neutrinos, we…

High Energy Physics - Phenomenology · Physics 2009-01-06 E. J. Chun , L. Velasco-Sevilla

The observed neutrino oscillations and baryon asymmetry, unexplained by the Standard Model (SM), can both be accounted for by extending the SM to include Majorana right-handed neutrinos (RHNs). Tiny neutrino masses naturally arise through…

High Energy Physics - Phenomenology · Physics 2025-06-26 Nobuchika Okada , Digesh Raut

We consider left-right symmetric model with spontaneous CP-violation. The Lagrangian of this model is CP invariant and the Yukawa couplings are real. Due to spontaneous breaking of the gauge symmetry, some of the neutral Higgses acquire…

High Energy Physics - Phenomenology · Physics 2014-11-18 Narendra Sahu , S. Uma Sankar

We study the connection between absolute neutrino mass and neutrino mixing parameters within $SO(10)$-inspired leptogenesis. We show that current favoured values of the unknown neutrino mixing parameters point toward values of the absolute…

High Energy Physics - Phenomenology · Physics 2021-06-04 Pasquale Di Bari , Rome Samanta

We consider the possibility of simultaneously addressing the baryon asymmetry of the Universe, the dark matter problem and the neutrino mass generation in minimal extensions of the Standard Model via sterile fermions with (small) total…

High Energy Physics - Phenomenology · Physics 2018-03-20 Asmaa Abada , Giorgio Arcadi , Valerie Domcke , Michele Lucente

We study the model with three right-handed neutrinos which masses are smaller than the weak scale ${\cal O}(10^2)$ GeV (called as the $\nu$MSM). The model can explain the origin of neutrino masses by the seesaw mechanism, offer a candidate…

High Energy Physics - Phenomenology · Physics 2015-06-02 Takehiko Asaka , Shintaro Eijima , Kazuhiro Takeda

The generation of the right amount of baryon asymmetry $\eta$ of the Universe from supersymmetric leptogenesis is studied within the type-I seesaw framework with three heavy singlet Majorana neutrinos $N_i\,\,(i = 1,2,3)$ and their…

High Energy Physics - Phenomenology · Physics 2011-01-28 Biswajit Adhikary , Ambar Ghosal , Probir Roy

Baryogenesis via leptogenesis is investigated in a specific model of light neutrino masses and mixing angles. The latter was proposed on the basis of an assumed complex-extended scaling property of the neutrino Majorana mass matrix $M_\nu$,…

High Energy Physics - Phenomenology · Physics 2017-03-22 Rome Samanta , Mainak Chakraborty , Probir Roy , Ambar Ghosal

The effective Majorana mass which determines the rate of the neutrinoless double beta decay, |<m>|, is considered in the case of three-neutrino mixing and massive Majorana neutrinos. Assuming a rather precise determination of the parameters…

High Energy Physics - Phenomenology · Physics 2011-04-20 S. Pascoli , S. T. Petcov , L. Wolfenstein

The usual see-saw formula is modified by the presence of two Higgs triplets in left-right symmetric theories. The contribution from the left-handed Higgs triplet to the see-saw formula can dominate over the conventional one when the…

High Energy Physics - Phenomenology · Physics 2010-02-03 A. S. Joshipura , E. A. Paschos , W. Rodejohann

We investigate under which circumstances one can show the existence of leptonic CP violation with the help of a positive or negative signal in neutrinoless double beta decay. The possibilities of cancellations are investigated for special…

High Energy Physics - Phenomenology · Physics 2007-05-23 W. Rodejohann

A detailed analytic and numerical study of baryogenesis through leptogenesis is performed in the framework of the standard model of electroweak interactions extended by the addition of three right-handed neutrinos, leading to the seesaw…

High Energy Physics - Phenomenology · Physics 2011-07-19 G. C. Branco , R. Gonzalez Felipe , F. R. Joaquim , M. N. Rebelo