Related papers: Models of maximal atmospheric neutrino mixing and …
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…
We propose a discrete non-abelian symmetry group which enforces maximal atmospheric neutrino mixing, while $\theta_{13} = 0$ and the solar mixing angle $\theta_{12}$ remains undetermined; without finetuning, $\theta_{12}$ will be large but…
We study the prediction for leptogenesis in two renormalizable supersymmetric $SO(10)\times A_4$ modular models in which the neutrino mass is dominantly generated by the type I seesaw mechanism. The evolution of the lepton asymmetries are…
If an exact $\mu\leftrightarrow \tau$ symmetry is the explanation of the maximal atmospheric neutrino mixing angle, it has interesting implications for origin of matter via leptogenesis in models where small neutrino masses arise via the…
We discuss a model for the lepton sector based on the seesaw mechanism and on a $D_4$ family symmetry. The model predicts the mixing angle $\theta_{13}$ to vanish. The solar mixing angle $\theta_{12}$ is free--it will in general be large if…
In this talk we show how a natural neutrino mass hierarchy can follow from the type I see-saw mechanism, and a natural neutrino mass degeneracy from the type II see-saw mechanism, where the bi-large mixing angles can arise from either the…
In the framework of type II seesaw mechanism we propose two simple but instructive ansatze for neutrino mixing and leptogenesis. In each ansatz, the effective Majorana neutrino mass matrix is composed of two parts -- the part with Z_2…
We consider the see-saw mechanism for hierarchical Dirac and Majorana neutrino mass matrices m_D and M_R, including the CP violating phases. Simple arguments about the structure of the neutrino mass matrix and the requirement of successful…
In the context of the seesaw mechanism, it is natural that the large solar and atmospheric neutrino mixing angles originate separately from large 2 by 2 mixings in the neutrino and charged-lepton sectors, respectively, and large mixing in…
We present an S$_4$ flavour symmetric model within a minimal seesaw framework resulting in mass matrices that leads to TM$_1$ mixing. Minimal seesaw is realized by adding two right-handed neutrinos to the Standard Model. The model predicts…
We address the issue of the neutrino masses and mixing in TeV scale $B-L$ extension of the Standard Model. We show that if Dirac neutrino masses are of order $10^{-4}$ Gev, then the measured neutrino masses are correctly obtained. We…
We discuss two types of neutrino mass matrices which both give $\theta_{23} = 45^\circ$, i.e., a maximal atmospheric mixing angle. We review three models, based on the seesaw mechanism and on simple extensions of the scalar sector of the…
We propose a renormalizable multi-Higgs model with $A_{4}\otimes Z_{2}\otimes Z^{\prime}_{2}$ symmetry, accounting for the experimental deviation from the tribimaximal mixing pattern of the neutrino mixing matrix. In this framework we study…
In this short review I discuss how high energy (type I) seesaw models can be nicely embedded within grand-unified models and reproduce the observed matter-antimatter asymmetry with leptogenesis. In particular, after discussing general…
It is well-known that, in the basis where the charged-lepton mass matrix is diagonal, there are seven cases of two texture zeros in Majorana neutrino mass matrices that are compatible with all experimental data. We show that two of these…
We consider the see-saw mechanism within a non-supersymmetric SO(10) model. By assuming the SO(10) quark-lepton symmetry, and after imposing suitable conditions that ensure that the right-handed (RH) neutrino masses are at most mildly…
We propose a unique lepton mixing scheme and its association with an exact hierarchy-philic neutrino mass matrix texture in the light of Type-I+Type-II seesaw mechanism under the framework of $A_4 \times Z_{10}$ discrete flavour symmetry.…
In the framework of the seesaw mechanism with three heavy right-handed Majorana neutrinos and no Higgs triplets we carry out a systematic study of the structure of the right-handed neutrino sector. Using the current low-energy neutrino data…
We consider a simple extension of the Standard Model providing dark matter and a TeV-scale seesaw mechanism that also allows for viable leptogenesis. In addition to the Standard Model degrees of freedom, the model contains a neutrinophilic…
We propose a predictive lepton model under a modular $S_4$ symmetry, where the neutrino mass matrix arises from a radiative seesaw at one-loop level. The tree-level mass matrix is forbidden by well-assigned modular weights, which also play…