Related papers: Predictions from the Fritzsch-Type Lepton Mass Mat…
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 examine the constraints on the MNS lepton mixing matrix =66rom the present and future experimental data of the neutrino oscillation, tritium beta decay, and neutrinoless double beta decay for Majorana neutrinos. We show that the small…
After the successful measurement of the mixing angle $\theta_{13}$, the determination of the neutrino mass hierarchy has become a priority for future neutrino experiments. We propose a conventional $\nu_\mu$ beam with neutrino energies in…
Based on an approach to quark and lepton masses, where the mass spectra originate in vacuum expectation values of U(3) flavor nonet (gauge singlet) scalars, neutrino masses and mixing are investigated. As an offshoot of this approach, it is…
On the basis of a seesaw-type mass matrix model for quarks and leptons, $M_f \simeq m_L M_F^{-1} m_R$, where $m_L\propto m_R$ are universal for $f=u,d,\nu$ and $e$ (up-quark-, down-quark-, neutrino- and charged lepton-sectors), and $M_F$…
We propose a $B-L$ model combined with the $S_4\times Z_3\times Z_4$ discrete symmetry which successfully explains the recent $3+1$ sterile - active neutrino data. The smallness of neutrino mass is obtained through the type-I seesaw…
There are three observables related to neutrino mass, namely the kinematic mass in direct searches, the effective mass in neutrino-less double beta decay, and the sum of neutrino masses in cosmology. In the limit of exactly degenerate…
We study the implications of a large $\nu_\mu - \nu_\tau$ mixing angle on lepton flavour violating radiative transitions in supersymmetric extensions of the standard model. The transition rates are calculated to leading order in $\epsilon$,…
Neutrino masses and mixings are analyzed in terms of left-handed fields and a 6x6 complex symmetric mass matrix whose singular values are the neutrino masses. An angle x_nu characterizes the kind of the neutrinos, with x_nu = 0 for Dirac…
To quantitatively assess the impact of an eV-mass sterile neutrino on the neutrinoless double-beta ($0\nu \beta \beta$) decays, we calculate the posterior probability distribution of the relevant effective neutrino mass $|m^\prime_{ee}|$ in…
We propose two phenomenological scenarios of lepton mass matrices and show that either of them can exactly give rise to \tan^2\theta_{13} = m_e/(m_e + 2m_\mu), \tan^2\theta_{23} = m_\mu/(m_e + m_\mu) and \tan^2\theta_{12} = (m_e m_2 +…
A neutrino mass matrix is considered under conditions of a CP invariance and a small reactor mixing $\theta_{13}$ angle. Absolute mass values for three neutrinos are evaluated for normal and inverted hierarchy spectra on the ground of data…
We discuss mass matrices with four texture zeros for the quarks and leptons. The three mixing angles for the quarks and leptons are functions of the fermion masses. The results agree with the experimental data. The ratio of the masses of…
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…
Based on existing data, we argue for a peculiar structure of the neutrino mass matrix, that has a block of relatively large elements--a dominant block. We analyze this ansatz and extract its predictions, assuming that the O(1) coefficients…
We investigate models of charged lepton and neutrino masses and lepton mixing based on broken modular symmetry. The matter fields in these models are assumed to transform in irreducible representations of the finite modular group $\Gamma_4…
Taking into account the latest neutrino oscillation data, we study texture zeros of the lepton mass matrices. Assuming the Dirac neutrino mass matrix M_D, the charged-lepton mass matrix M_l and the mass matrix of heavy right-handed Majorana…
Recently an upper bound on the rate of the lepton number violating decay $K^+\to \mu^+\mu^+\pi^-$ has been significantly reduced by the E865 experiment at BNL and further improvement is expected in the near future. We study this process as…
The NuTeV experiment at Fermilab presents a determination of the electroweak mixing angle. High purity, large statistics samples of muon-neutrino and muon-antineutrino events allow the use of the Paschos-Wolfenstein relation. This…
We present a model of neutrino mixing based on the flavour group $\Delta(27)$ in order to account for the observation of a non-zero reactor mixing angle ($\theta_{13}$). The model provides a common flavour structure for the charged-lepton…