Related papers: High Scale Mixing Unification for Dirac Neutrinos
Typically in unified theories the neutrino mixing angles, like the Cabibbo-Kobayashi-Maskawa (CKM) angles of the quarks, are related to the small mass ratios between fermions of different generations and are therefore quite small. A new…
We study leptogenesis in two seesaw models where maximal atmospheric neutrino mixing and $U_{e3} = 0$ result from symmetries. Salient features of those models are the existence of three Higgs doublets and a twofold degeneracy of the…
Unlike the standard model where neutrino masses can be made arbitrarily small, we find in the minimal left-right symmetric model that Dirac type Yukawa coupling $h_D \sim 10^{-4.2}$ for $\nu_\tau$ is generated from charged fermion Yukawa…
As an extension of our previous work in the seesaw mechanism, we analyze the influence of $U_{e3}$ on the properties (masses and mixing) of the RH Majorana neutrinos in three flavors. The quasidegenerate light neutrinos case is also…
The implications of a large value of the effective Majorana neutrino mass for a class of two texture zero neutrino mass matrices have been studied in the flavor basis. It is found that these textures predict near maximal atmospheric…
In the light of the recent measurement of the leptonic mixing angle $\theta_{13}$, implications of the latest mixing data have been investigated for non-minimal textures of lepton mass matrices assuming the neutrinos to be Majorana like.…
Two general models with hierarchical and almost degenerate neutrino masses, which are able to explain the solar and atmospheric anomalies are investigated. We show how neutrinoless double beta decay experiments discern Dirac and Majorana…
We have studied mixing and masses of three left handed Majorana neutrinos in the model, which assumes exactly degenerate neutrino masses at some "neutrino unification" scale. Such a simple theoretical ansatz naturally leads to…
Guided by considerations of flavour symmetry, we construct a set of exact Standard Model (SM) renormalisation group evolution invariants which link quark masses and mixing parameters. We examine their phenomenological implications and infer…
In analogy to the mixing pattern of the pseudoscalar mesons in QCD we discuss the mixing of massive neutrinos. Unlike the quarks flavor mixing angles the leptonic mixing angles are large, nearly maximal. The three massive neutrinos are…
A simple mechanism to generate Dirac masses for the neutrinos in SU(5) supersymmetric grand unified theory is proposed. The tiny Dirac masses are induced by the small mixing between the Higgs fields and another superheavy fields. The mixing…
We discuss the conditions for a non-vanishing Dirac phase \delta and mixing angle \theta_{13}, sources of CP violation in neutrino oscillations, to be uniquely responsible for the observed matter-antimatter asymmetry of the universe through…
I demonstrate that neutrino large mixing between $\nu_\mu$ and $\nu_\tau$ are naturally reproduced using a novel mechanism called `E-twisting'in a supersymmetric $E_6$ grand unification model. This model explains all the characteristic…
We consider a neutrino mass model where all leptonic mixing is induced by a heavy Majorana sector through the seesaw type I mechanism, while the Dirac mass matrices are diagonal. Such a pattern occurs naturally in grand unified theories.…
In our previous paper, we proposed the democratic-type neutrino mass matrix which gives interesting predictions, $\theta_{23}=-\frac{\pi}4$, $|\tan \theta_{12}|=\sqrt{2-3\sin^2 \theta_{13}}$ and $\delta=\frac {\pi}2$, where $\theta_{ij}$ is…
Sum rules in the lepton sector provide an extremely valuable tool to classify flavour models in terms of relations between neutrino masses and mixing parameters testable in a plethora of experiments. In this manuscript we identify new…
A model is considered in which the scale of the heavy singlet neutrinos is a few orders of magnitude below the grand unification scale and where right-handed vector bosons play still a negligible role. In a basis with diagonal up-quark and…
We construct a class of renormalizable models for lepton mixing that generate predictions given in terms of the charged-lepton mass ratios. We show that one of those models leads, when one takes into account the known experimental values,…
We reconsider decays of pseudoscalar mesons (P) to neutrino pairs and possibly additional photons in presence of (light) Majorana neutrinos. For this purpose we derive a model-independent general parametrization of neutrino mass matrices…
We analyse, within the framework of universal strength for Yukawa couplings (USY), various structures for the Dirac and Majorana neutrino mass matrices giving rise, through the see-saw mechanism, to a degenerate mass spectrum. A specific…