Related papers: Form Invariance and Symmetry in the Neutrino Mass …
We study the consequences of the $Z_2$-symmetry behind the $\mu$--$\tau$ universality in neutrino mass matrix. We then implement this symmetry in the type-I seesaw mechanism and show how it can accommodate all sorts of lepton mass…
A previous short analysis of the seesaw mechanism, based on quark-lepton symmetry, experimental data and hierarchical neutrino spectrum, is enlarged to include small but not zero U_{e3}, inverted mass hierarchy, and the qualitative effect…
We consider the neutrino physics of models with a sequentially broken U(2) flavor symmetry. Such theories yield the observed pattern of quark and lepton masses, while maintaining sufficient degeneracies between superparticles of the first…
Motivated by the Super-Kamiokande data, we revisit models with U(1) symmetries and discuss the origin of neutrino masses and mixings in such theories. We show that, in models with just three light neutrinos and a hierarchy of neutrino…
Neutrino oscillation experiments (excluding the LSND experiment) suggest a tri-bimaximal form for the lepton mixing matrix. This form indicates that the mixing matrix is probably independent of the lepton masses, and suggests the action of…
Using an $SO(10)$-inspired form for the Dirac neutrino mass, we map the neutrino data to right-handed neutrino Majorana mass-matrix, $\mathcal M$, and investigate a special form with \emph{seesaw} tribimaximal mixing; it predicts a normal…
We derive in a simple way the $(Z_2)^3$ symmetry which characterizes uniquely the phenomenologically successful tripartite form leading to the tribimaximal mixing in the neutrino mass matrix. We impose this symmetry in a setup including the…
An effective texture is presented for six Majorana neutrinos, three active and three (conventional) sterile, based on a 6x6 mass matrix whose 3x3 Dirac component (i.e., active--sterile component) is conjectured to get a hierarchical fermion…
It has been recently claimed that the symmetry group S4 yields to the Tri-bimaximal neutrino mixing in a "natural" way from the group theory point of view. Approving of this feature as an indication, we build a supersymmetric model of…
We study neutrino masses and mixing in the context of flavor models with A4 symmetry, three scalar doublets in the triplet representation, and three lepton families. We show that there is no representation assignment that yields a…
We explore a new class of supersymmetric models for lepton masses and mixing angles where the role of flavour symmetry is played by modular invariance. The building blocks are modular forms of level N and matter supermultiplets, both…
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 propose a model based on the gauge group $SU(3)_{C}\otimes SU(3)_{L}\otimes U(1)_{X}$ with an extra $S_{3}$ flavor symmetry, which accounts for the lepton masses and mixing. The small active neutrino masses are generated via a double…
We look for predictive flavour patterns of the effective Majorana neutrino mass matrix that are compatible with current neutrino oscillation data. Our search is based on the assumption that the neutrino mass matrix contains equal elements…
The discrete subgroup Delta(27) of SU(3) has some interesting properties which may be useful for understanding charged-lepton and neutrino mass matrices. Assigning leptons to the 3 and 3* representations of Delta(27), a simple form of the…
We study a seesaw-type extension of the Standard Model in which the symmetry group is enlarged by a global U(1). We introduce adequate scalar and fermion representations which naturally explain the smallness of neutrino masses. With the…
We study the origin of neutrino mass through lepton-number violation and spontaneous $U(1)_{L_\mu-L_\tau}$ symmetry breaking. To accomplish the purpose, we include one Higgs triplet, two singlet scalars, and two vector-like doublet leptons…
We have studied the most general neutrino mass matrices in models with SU(2) and SU(3) horizontal symmetries. Without going into the details of the models it is possible to write down the effective operators, which predict the structure of…
The charged lepton mass formula can be explained when the masses are propotinal to the squared vacuum expectation values (VEVs) of scalar fields. We introduce U(3) flavor symmetry and its nonet scalar field $\Phi$, whose VEV structure plays…
Implication of neutrino mass model based on $\Delta$(27) discrete flavor symmetry, on parameters of neutrino oscillations, CP violation and effective neutrino masses is studied using type-I seesaw mechanism. The Standard Model particle…