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Related papers: Cobimaximal Mixing with Dirac Neutrinos

200 papers

We consider a class of models of neutrino mixing with $S_4$ flavour symmetry and generalised CP symmetry, broken to $Z_2$ and $Z_2 \times {\rm CP}$ residual symmetries in the charged lepton and neutrino sectors, respectively. In this…

High Energy Physics - Phenomenology · Physics 2018-03-30 J. T. Penedo , S. T. Petcov , A. V. Titov

The Tri-Bi-Maximal pattern has been long investigated as the symmetric scenario that lies behind the neutrino mixing matrix. It predicts a null reactor angle and hence forbids $CP$ violation in the lepton sector, which is in contrast to the…

High Energy Physics - Phenomenology · Physics 2021-03-17 Diana C. Rivera-Agudelo , S. L. Tostado

We propose a simple framework based on $\Delta(27)$ that leads to the successful cobimaximal lepton mixing ansatz, thus providing a predictive explanation for leptonic mixing observables. We explore first the effective neutrino mass…

High Energy Physics - Phenomenology · Physics 2020-05-20 A. E. Cárcamo Hernández , Ivo de Medeiros Varzielas

The compelling experimental evidences for oscillations of solar, atmospheric and reactor neutrinos imply the existence of 3-neutrino mixing in vacuum. We review the phenomenology of 3-neutrino mixing, and the current data on the 3-neutrino…

High Energy Physics - Phenomenology · Physics 2009-11-10 S. T. Petcov

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

We study mixing of the Dirac neutrinos in the residual symmetries approach. The key difference from the Majorana case is that the Dirac mass matrix may have larger symmetries: $G_\nu=\mathbf{Z}_{n}$ with $n\geq3$. The symmetry group…

High Energy Physics - Phenomenology · Physics 2015-12-02 Arman Esmaili , Alexei Yu. Smirnov

We propose a democratic-type neutrino mass matrix based on $Z_3$ symmetry. This mass matrix predicts the CP violation phase, $\delta=\pi/2$, and the mixing angle between the mass eigenstates $\nu_2$ and $\nu_3$, $\sin^2 \theta_{23}= \cos^2…

High Energy Physics - Phenomenology · Physics 2009-10-31 Kiko Fukuura , Takahiro Miura , Eiichi Takasugi , Masaki Yoshimura

Possible alternatives to tri-bimaximal mixing are presented based on other symmetry principles, and their predictions for |U_{e3}|, sin^2 theta_{12} and sin^2 theta_{23} are compared to the present neutrino mixing data. In some cases…

High Energy Physics - Phenomenology · Physics 2010-12-15 Carl H. Albright , Alexander Dueck , Werner Rodejohann

We present a model where Majorana neutrino mass terms are forbidden by the flavor symmetry group Delta(27). Neutrinos are Dirac fermions and their masses arise in the same way as that of the charged fermions, due to very small Yukawa…

High Energy Physics - Phenomenology · Physics 2014-04-17 Alfredo Aranda , Cesar Bonilla , S. Morisi , E. Peinado , J. W. F. Valle

Model-independent consequences of applying a generalized hidden horizontal Z_2 symmetry to the neutrino mass matrix are explored. The Dirac CP phase delta_D can be expressed in terms of the three mixing angles as 4 c_a s_a c_s s_s s_x cos…

High Energy Physics - Phenomenology · Physics 2011-08-11 Shao-Feng Ge , Duane A. Dicus , Wayne W. Repko

The near maximal value for the atmospheric neutrino mixing angle together with the fact that the solar mixing angle satisfies the relation $\sin^2\theta_\odot\simeq {1/3}$ is the basis for the so called tri-bimaximal mixing (tbm) when…

High Energy Physics - Phenomenology · Physics 2010-04-06 R. N. Mohapatra , S. Nasri , Hai-Bo Yu

It is argued that data from atmospheric and solar neutrino experiments point strongly to tri-maximal or bi-maximal lepton mixing. While (`optimised') bi-maximal mixing gives an excellent a posteriori fit to the data, tri-maximal mixing is…

High Energy Physics - Phenomenology · Physics 2009-10-31 W. G. Scott

We show that in a recently proposed $S_3$ model for tri-bimaximal mixing pattern for neutrinos, CP violating phases in neutrino mixings are directly responsible for lepton asymmetry $\epsilon_\ell$. In the exact tri-bimaximal limit,…

High Energy Physics - Phenomenology · Physics 2008-11-26 R. N. Mohapatra , Hai-Bo Yu

Suppose the geometrical explaination to the weak CP phase in quark sector is also valid for neutrinos, the mixing and CP violation in neutrino system are discussed. We find a larger $J_{CP}$ than $3\times 10^{-3}$ implys the large-mixing…

High Energy Physics - Phenomenology · Physics 2018-01-17 Yong Liu , Utpal Sarkar

The Majorana neutrino mass textures with a texture zero and a vanishing cofactor are reconsidered in the light of current experimental results. A numerical and systematic analysis is carried out for all viable patterns. In particular, we…

High Energy Physics - Phenomenology · Physics 2014-05-21 Weijian Wang , Dong-Jiang Zhang

We present neutrino mass matrices which predict the atmospheric neutrino mixing to be almost maximal, $\sin^2 2\theta_{atm}>0.999$, as well as the large solar neutrino mixing, $8/9>\sin^2 2\theta_{sol}>0.87$, and the large CP violation (the…

High Energy Physics - Phenomenology · Physics 2009-12-31 Takahiro Miura , Eiichi Takasugi , Masaki Yoshimura

The basic characteristics used for the description of both Dirac and Majorana massive neutrinos are studied. Currently available experimental data for these characteristics are presented with an evidence of possible anomalies beyond the…

High Energy Physics - Phenomenology · Physics 2013-10-23 N. Yu. Zysina , S. V. Fomichev , V. V. Khruschov

The status of the problem of neutrino masses and mixing is shortly reviewed. Different schemes of mixing of (Dirac or Majorana) massive neutrinos are considered. The theory of neutrino oscillations in vacuum and in matter is presented.…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. M. Bilenky

A model of a neutrino mixing with an $A_4\times Z_3\times Z_4$ flavour symmetry is suggested. In addition to the standard model fields, the present model contains six new fields which transform under different representations of $A_4\times…

High Energy Physics - Phenomenology · Physics 2016-11-23 Nguyen Anh Ky , Phi Quang Van , Nguyen Thi Hong Van

We propose a scheme of lepton mixing in which the unitary matrix that diagonalizes the neutrino mass matrix is bimaximal and the deviation from bimaximal of the lepton mixing matrix is due to the unitary matrix that diagonalizes the…

High Energy Physics - Phenomenology · Physics 2009-11-07 C. Giunti , M. Tanimoto