Related papers: The standard HVM
We present a model that extends the standard model by incorporating the simplest discrete symmetry groups, $Z_2$ and $Z_3$. This model introduces vector-like leptons and a real scalar singlet. Based on this framework, we generate Dirac…
We develop an $A_4 \times Z_4 \times Z_2$ symmetry extension of Standard Model under the minimal extended seesaw (MES) mechanism which successfully predicts neutrino masses and mixings patterns. This model breaks $\mu-\tau$ symmetry of…
We formulate a predictive model of fermion masses and mixings based on a $\Delta(27)$ family symmetry. In the quark sector the model leads to the viable mixing inspired texture where the Cabibbo angle comes from the down quark sector and…
We phenomenologically build a neutrino mass matrix obeying $\mu-\tau$ symmetry with only two parameters, Cabibbo angle $(\lambda)$ and a flavour twister parameter $(\eta)$. For vanishing $\eta$, the model assumes TBM mixing. When…
We speculate that the mass spectrum of three neutrinos might have a normal hierarchy as that of three charged leptons or that of three up-type (or down-type) quarks. In this spirit, we propose a novel parametrization of the $3\times 3$…
An attempt is made to explore the possibility for deviations of solar mixing angle ($\theta_{12}$) from tri-bimaximal mixings, without sacrificing the predictions of maximal atmospheric mixing angle ($\theta_{23}=\pi/4$) and zero reactor…
We adopt a bottom-up approach to reconstruct the possible neutrino mass matrix patterns, in the hypothesis that $\lambda = \sin \theta_C$, where $\theta_C$ is the Cabibbo angle, is a useful expansion parameter in the neutrino sector as it…
We discuss a particularly symmetric model of neutrino mixings where, with good accuracy, the atmospheric mixing angle theta_{23} is maximal, theta_{13}=0 and the solar angle satisfies sin^2(theta_{12})=1/3 (Harrison-Perkins-Scott (HPS)…
CP violation in the lepton sector, and other aspects of neutrino physics, are studied within a high scale supersymmetry model. In addition to the sneutrino vacuum expectation values (VEVs), the heavy vector-like triplet also contributes to…
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…
A simple extension of the Standard Model providing TeV scale seesaw mechanism is presented. Beside the Standard Model particles and right-handed Majorana neutrinos, the model contains a singly charged scalar, an extra Higgs doublet and…
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…
We consider theories where the Standard Model (SM) neutrinos acquire masses through the seesaw mechanism at the weak scale. We show that in such a scenario, the requirement that any pre-existing baryon asymmetry, regardless of its origin,…
We propose a model of quark and lepton mixing based on the tetrahedral A(4) family symmetry with quark-lepton unification via the tetra-colour Pati-Salam gauge group SU(4)_{PS}, together with SU(2)_L x U(1)_R. The "tetra-model" solves many…
We propose a model where Dirac neutrino mass is obtained from small vacuum expectation value (VEV) of neutrino-specific Higgs doublet without fine-tuning problem. The small VEV results from a seesaw-like formula with the high energy scale…
Assuming lepton number conservation, hermiticity of the neutrino mass matrix and $\nu_{\mu} - \nu_{\tau}$ exchange symmetry, we show that we can determine the neutrino mass matrix completely from the existing data. Comparing with the…
Flavor symmetry ($T^{'} \times Z_2$) where $T^{'}$ is the binary tetrahedral group predicts for neutrino mixing angles $\theta_{13} = \sqrt{2} (\frac{\pi}{4} - \theta_{23})$ and, with one phenomenological input, provides upper and lower…
We consider a minimal condition that predicts the 1-3 lepton mixing angle $\theta_{13} \simeq \theta_{\rm C}/\sqrt{2}$ with $\theta_{\rm C}$ the Cabibbo angle, and give the improved prediction of $\theta_{13}$. In the case of normal mass…
We revisit the possibility of relating lepton mixing angles with lepton mass hierarchies in a model-independent way. Guided by the existence of such relations in the quark sector, we first consider all the mixing angles, both in charged…
We present a new realization of inverted neutrino mass hierarchy based on $S_3 \times {\cal U}(1)$ flavor symmetry. In this scenario, the deviation of the solar oscillation angle from $\pi/4$ is correlated with the value of $\theta_{13}$,…