Related papers: Constraining {\it CP} violation in a softly broken…
We propose a simple renormalizable model for the spontaneous CP violation based on $SU(2)_{L}\times U(1)_{Y}\times A_{4}$ symmetry in a radiative seesaw mechanism, which can be guaranteed by an extra $Z_{2}$ symmetry. In our model CP is…
Supersymmetric models with broken R-parity induced by lepton number violating terms provide a calculable framework for neutrino masses and mixings. Within models with bilinear R-parity breaking six new physical phases appear which are…
We study effects of CP violation in a modified bipair neutrino mixing scheme predicting $\sin^2\theta_{23}$ near both 0.4 and 0.6 currently consistent with experimentally allowed values. The source of CP violation is supplied by charged…
We propose a 3-3-1 model with neutral fermions based on $A_4$ flavor symmetry responsible for fermion masses and mixings with non-zero $\theta_{13}$. To get realistic neutrino mixing, we just add a new $SU(3)_L$ triplet being in…
Based on a neutrino mass matrix model in which a 2-3 symmetry is only broken by a phase parameter, it is investigated how the lepton mixing matrix can deviate from the so-called tribimaximal mixing under a condition that CP is maximally…
We discuss a simple model of lepton mixing and CP violation based on the flavor democracy of charge leptons and the mass degeneracy of neutrinos. A nearly bi-maximal flavor mixing pattern, which is favored by current data on atmospheric and…
I propose a model of radiative charged-lepton and neutrino masses with $A_4$ symmetry. The soft breaking of $A_4$ to $Z_3$ lepton triality is accomplished by dimension-three terms. The breaking of $Z_3$ by dimension-two terms allow…
We study a class of models for neutrino mass matrix in Type-II seesaw with $A_4$ family symmetry. The resulting neutrino mass matrix can be naturally made to respect a $\mu-\tau$ exchange plus CP conjugate symmetry (GLS) with the CP…
We show that the simultaneous determination of the leptonic CP-odd phase $\delta$ and the angle $\theta_{13}$ from the subleading transitions $\nu_e\to\nu_\mu$ and ${\bar\nu}_e\to{\bar\nu}_\mu$ results generically, at fixed neutrino energy…
We have shown that non-zero U_{e3} is generated in a see-saw type softly broken A_4 symmetric model through a single parameter perturbation in m_D in a single element. We have explored all possible 9 cases to study the neutrino mixing…
Recently Babu, Ma and Valle proposed a model of quark and lepton mixing based on $A_4$ symmetry. Within this model the lepton and slepton mixings are intimately related. We perform a numerical study in order to derive the slepton masses and…
The recent measurement of the third lepton mixing angle, \theta_{13}, has shown that, although small compared to \theta_{12} and \theta_{23}, it is much larger than anticipated in schemes that generate Tri-Bi-Maximal (TBM) or Golden Ratio…
We perform a comprehensive study of family symmetry models based on $A_4$ combined with the generalised CP symmetry $H_{\rm{CP}}$. We investigate the lepton mixing parameters which can be obtained from the original symmetry $A_4\rtimes…
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…
The $\mu$-$\tau$ exchange symmetry in the neutrino mass matrix and its breaking as a perturbation are discussed. The exact $\mu$-$\tau$ symmetry restricts the 2-3 and 1-3 neutrino mixing angles as $\theta_{23} = \pi/4$ and $\theta_{13} = 0$…
We further study the "complementary" Ansatz, Tr$(M_\nu)$=0, for a prediagonal light Majorana type neutrino mass matrix. Previously, this was studied for the CP conserving case and the case where the two Majorana type CP violating phases…
A model of a neutrino mixing with an $A_4\times Z_3\times Z_4$ flavour symmetry is suggested. In addition to the standard model fields, the present model contains six new fields which transform under different representations of $A_4\times…
The observation of neutrino masses leads to the possibility of leptonic mixing and CP violation. One of the simplest extensions of the Standard Model giving rise to neutrino masses consists of the introduction of one righthanded neutrino…
The smallness of the 1-3 lepton mixing angle $\theta_{13}$ and of the neutrino mass-squared-difference ratio $\Delta m^2_{12}/\Delta m^2_{23}$ can be understood as the departure from a common limit where they both vanish. We discuss in…
Soft supersymmetry breaking terms involving heavy singlet sneutrinos provide new sources of lepton number violation and of CP violation. In addition to the CP violation in mixing, investigated previously, we find that `soft leptogenesis'…