Related papers: A three-parameter model for the neutrino mass matr…
We apply the discrete S_3 flavor symmetry to both lepton and quark sectors of the standard model extended by introducing one Higgs triplet and realizing the type-II seesaw mechanism for finite neutrino masses. The resultant mass matrices of…
We suggest a simple model, based on the type-I seesaw mechanism, for the lepton mass matrices. The model hinges on an Abelian symmetry which leads to mass matrices with some vanishing matrix elements. The model predicts one massless…
We consider the problem of neutrino masses and mixing angles in a supersymmetric model based on the gauge group SU(4)$\otimes$SU(2)$_L\otimes$SU(2)$_R$ broken at the scale $M_X\approx 10^{16}$ GeV. We extend a previous operator analysis of…
We propose a viable theory based on the $SU(3)_C\times SU(3)_L\times U(1)_X$ gauge group supplemented by the $S_4$ discrete group together with other various symmetries, whose spontaneous breaking gives rise to the current SM fermion mass…
Seesaw models with a slightly broken lepton number symmetry can explain small neutrino masses, and allow for low-scale leptogenesis. We make a thorough analysis of leptogenesis within the simplest model with two right-handed (RH) neutrinos…
We propose a renormalizable $T'$ flavor model based on the $SU(3)_C\times SU(3)_L\times U(1)_X\times U(1)_{\mathcal{L}}$ gauge symmetry, consistent with the observed pattern of lepton masses and mixings. The small masses of the light active…
As neutrino experiments are starting to probe the detailed structure of the neutrino mass matrix, we present sumrules relating its matrix elements for a class of models with approximate $L_e-L_{\mu}-L_{\tau}$ symmetry and the observables in…
We analyze the structure of quark and lepton mass matrices under the hypothesis that they are determined from a minimum principle applied to a generic potential invariant under the $\left[U(3)\right]^5\otimes {\mathcal O}(3)$ flavor…
Stimulated by a successful quark mass matrix model based on U(3)$\times$U(3)$'$ family symmetry, a phenomenological neutrino mass matrix for the Majorana neutrinos $(\nu_L, \nu_R^c, N_L, N_R^c)$ is proposed. The model has only three…
A natural extension of the standard $SU(2)_{\rm L} \times U(1)_{\rm Y}$ gauge model to accommodate massive neutrinos is to introduce one Higgs triplet and three right-handed Majorana neutrinos, leading to a $6\times 6$ neutrino mass matrix…
We provide the first systematic study of the viable parameter space for leptogenesis in the type-I seesaw model with three right-handed neutrinos whose Majorana masses lie below the electroweak scale. We highlight the very rich…
We develop a see-saw model for neutrino masses and mixing with an S3\times Z3 symmetry. It involves an interplay of Type-I and Type-II see-saw contributions of which the former is subdominant. The S3 \times Z3 quantum numbers of the fermion…
We study the implications of having a similarity between quark and lepton mixing in the Dirac sector of the Standard Model plus the right-handed neutrino. This enable us to describe all masses and mixings in the Dirac sector in terms of…
Plausible phenomenological consequences of the well-known Pisano-Pleitez- Frampton 3-3-1 model - such as the neutrino masses - are analyzed within the solution provided by the exact algebraical approach - proposed several years ago by…
We construct a model that allows us to determine the three neutrino masses directly from the experimental mass squared differences, $\Delta_{\rm atm}$ and $\Delta_{\rm sol}$, together with the assumption that $\Lambda = \surd (1/6) = \surd…
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…
An elegant model is proposed by extending the Standard Model using the $\Delta(27)\times Z_3 \times Z_{10}$ symmetry within the framework of the Type-I + Type-II seesaw mechanism. This model is particularly noteworthy for its ability to…
A special form of the $3 \times 3$ Majorana neutrino mass matrix derivable from $\mu - \tau$ interchange symmetry accompanied by a generalized $CP$ transformation was obtained many years ago. It predicts $\theta_{23} = \pi/4$ as well as…
We discuss the possibility of flavor symmetries to explain the pattern of charged lepton and neutrino masses and mixing angles. We emphasize what are the obstacles for the generation of an almost maximal atmospheric mixing and what are the…
Neutrino oscillations data indicates that neutrino mixings are consistent with an apparent $\nu_\mu - \nu_\tau$ exchange symmetry in neutrino mass matrix. We observe that in the mininimally extended standard model with the see-saw…