Related papers: U_{PMNS} = U_ell^dagger U_nu
Non-vanishing U_{e3} has been theoretically related to a certain flavor symmetry breaking in the neutrino sector. We propose a scenario to break the mu-tau symmetry so as to accommodate the non-vanishing U_{e3}. Our scenario is constructed…
We discuss a minimal predictive see-saw model in which the right-handed neutrino mainly responsible for the atmospheric neutrino mass has couplings to (nu_e, nu_mu, nu_tau) proportional to (0,1,1) and the right-handed neutrino mainly…
The recent measurement of the third lepton mixing angle, \theta_{13}, has shown that, although small compared to \theta_{12} and \theta_{23}, it is much larger than anticipated in schemes that generate Tri-Bi-Maximal (TBM) or Golden Ratio…
Experimental data have provided stringent constraints on neutrino mixing parameters. In the standard parameterization the mixing angle $\theta_{23}$ is close to $\pi/4$. There are also evidences show that the CP violating phase is close to…
We propose a seesaw scenario that possible corrections to the tribimaximal pattern of lepton mixing are due to the small phase splitting of the right-handed neutrino mass matrix. we show that the small deviations can be expressed…
We show that a modification of a recently proposed model by Altarelli and Feruglio with softly broken $A_4$ symmetry leads naturally to nonvanishing $U_{e3}$ with $\theta_{13}\simeq 2^o - 4^o$. The observed mass squared differences for…
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…
We discuss consequences of assuming that the (Majorana) neutrino mass matrix $M_\nu$ and the charged lepton mass matrix $M_l$ satisfy, $S_\nu^T M_\nu S_\nu=-M_\nu~,T_l^\dagger M_lM_l^\dagger T_l=M_lM_l^\dagger$ with respect to some discrete…
We study the effects of breaking S3 symmetry in the neutrino mass matrix for the masses and mixing matrix of neutrinos. At zeroth order the model gives degenerate neutrino masses and accommodates tribimaximal mixing. We introduce…
Using data from atmospheric neutrino mixing, and a simple functional form for mixing angles, the absolute values of three neutrino masses are calculated: $m_3\cong 5.37\times 10^{-2} eV$, $m_2\cong 1.94\times 10^{-2} eV$, $m_1\cong…
Large neutrino mixing angles suggest that the Yukawa sector is invariant under permutations of the fermion families. This S_{3} permutation symmetry is broken at a large energy scale but much below the unification scale. Assuming that the…
It has been said that the measurements of $U_{e3}$ in the lepton flavor mixing matrix would help discriminate between the possible solar neutrino solutions under the natural conditions with the neutrino mass hierarchies of $m_1 \ll m_2 \ll…
Harrison, Perkins and Scott have proposed simple charged lepton and neutrino mass matrices that lead to the tribimaximal mixing $U_{\rm TBM}$. We consider in this work an extension of the mass matrices so that the leptonic mixing matrix…
It is shown that the neutrino mass matrices in the flavour basis yielding a vanishing $U_{e3}$ are characterized by invariance under a class of $Z_2$ symmetries. A specific $Z_2$ in this class also leads to a maximal atmospheric mixing…
We reexamine the democratic neutrino mixing ansatz, in which the mass matrices of charged leptons and Majorana neutrinos arise respectively from the explicit breaking of S(3)_L x S(3)_R and S(3) flavor symmetries. It is shown that a…
The observed neutrino mixing, having a near maximal atmospheric neutrino mixing angle and a large solar mixing angle, is close to tri-bi-maximal, putting leptonic mixing in contrast with the small mixing of the quark sector. We discuss a…
We re-analyze charged lepton corrections to neutrino mixing angles and CP phases, carefully including CP phases from the charged lepton sector. We present simple analytical formulae for including the charged lepton corrections and derive…
The simplest unified extension of the MSSM with bi-linear R--Parity violation naturally predicts a hierarchical neutrino mass spectrum, in which one neutrino acquires mass by mixing with neutralinos, while the other two get mass…
We consider the possibility to gain information on the lepton mixing matrix element |U_{e3}| from an improved experimental limit on the effective neutrino mass governing neutrino-less double beta decay. We show that typically a lower limit…
The smallness of the $\theta_{13}$ mixing angle as observed in neutrino oscillation experiments can be understood through an approximated $\mu - \tau$ exchange symmetry in the neutrino mass matrix. Using recent oscillation neutrino data,…