Related papers: Bimaximal mixing from lopsided neutrinos
We consider the problem of neutrino masses and mixing within the framework of a non-minimal supersymmetric SU(5) model extended by adding a set of 1,24 chiral superfields accommodating three right-handed neutrinos. A Type I+III see-saw…
Minimal SO(10) grand unified models provide phenomenological predictions for neutrino mass patterns and mixing. These are the outcome of the interplay of several features, namely: i) the seesaw mechanism; ii) the presence of an intermediate…
This is a review article about neutrino mass models, particularly see-saw models involving three active neutrinos which are capable of describing both the atmospheric neutrino oscillation data, and the large mixing angle MSW solar solution,…
Based on a universal seesaw mass matrix model with three scalars \phi_i, and by assuming an S_3 flavor symmetry for the Yukawa interactions, the lepton masses and mixings are investigated systematically. In order to understand the observed…
In this talk, we discuss the implications of the renormalization group equations for the neutrino masses and mixing angles in a supersymmetric string-inspired SU(4) x SU(2)_L x SU(2)_R x U(1)_X model with matter in fundamental and…
If neutrino masses are obtained via the canonical seesaw mechanism, based on an underlying 2X2 mass matrix, unitarity violation of the neutrino mixing matrix is unavoidable, but its effect is extremely small. On the other hand, in the…
We consider a minimal formulation of SO(10) Grand Unified Theory wherein all the fermion masses arise from Yukawa couplings involving one 126 and one 10 of Higgs multiplets. It has recently been recognized that such theories can explain,…
We show that there exist six parallel textures of the charged lepton and neutrino mass matrices with six vanishing entries, whose phenomenological consequences are exactly the same. These {\it isomeric} lepton mass matrices are compatible…
We propose a simple model of the neutrino mass matrix which can explain the solar and atmospheric neutrino problems in a 3($\nu_L + \nu_R$) framework. Assuming that only two right-handed neutrinos are heavy and a Dirac mass matrix has a…
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 two Type-II seesaw scenarios for the neutrino mass matrix in the left-right symmetric model, in which the Higgs triplet Yukawa coupling matrix takes the appealing Friedberg-Lee texture. We show that the nearly tri-bimaximal…
We review the problem of neutrino masses and mixings in the context of Grand Unified Theories. After a brief summary of the present experimental status of neutrino physics, we describe how the see-saw mechanism can automatically account for…
We consider seesaw type-I models including at least one (mostly-)sterile neutrino with mass at the eV scale. Three distinct situations are found, where the presence of light extra neutrinos is naturally justified by an approximately…
In the minimal 3-3-1 model charged leptons come in a non-diagonal basis. Moreover the Yukawa interactions of the model lead to a non-hermitian charged lepton mass matrix. In other words, the minimal 3-3-1 model presents a very complex…
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…
I review promising approaches to neutrino mass models, focussing on three neutrino patterns of neutrino masses and mixing angles, and the corresponding Majorana mass matrices. I discuss the see-saw mechanism, and show how it may be applied…
We account for the solar and atmospheric neutrino problems by introducing maximal mixing between conventional and sterile neutrino partners. We achieve this by invoking a seesaw-like mechanism which not only provides us with maximally mixed…
We propose a simple but suggestive seesaw model with two phenomenological conjectures: three heavy (right-handed) Majorana neutrinos are degenerate in mass in the symmetry limit and three light Majorana neutrinos have the tri-bimaximal…
Restrictions on the neutrino masses and lepton mixing are reviewed. Solar, atmospheric and relic neutrinos give the indications of existence of nonzero neutrino masses and mixing. The data pick up two regions of mixing angles which are or…
We study models of neutrino masses which naturally give rise to an inverted mass hierarchy and bi-maximal mixing. The models are based on the see-saw mechanism with three right-handed neutrinos, which generates a single mass term of the…