Related papers: Simple neutrino mass matrix with only two free par…
We study the models with the Majorana neutrino masses generated radiatively by two-loop diagrams due to the Yukawa $\rho \bar \ell_R^c \ell_R$ and effective $\rho^{\pm\pm} W^\mp W^\mp$ couplings along with a scalar triplet $\Delta$, where…
Using the type-II seesaw mechanism with three Higgs doublets phi_alpha (alpha = e, mu, tau) and four Higgs triplets, we build a model for lepton mixing based on a 384-element horizontal symmetry group, generated by the permutation group S_3…
We consider the simplest extension of the standard electroweak model by one sterile neutrino that allows for neutrino masses and mixing. We find that its leptonic sector contains much less free physical parameters than previously realized.…
We revisit the Fritzsch-type lepton mass matrix models confronted with new experiments for neutrino mixings. It is shown that the model is viable and leads to a rather narrow range of free parameters. Using empirical mixing information…
Under the assumption of symmetric four zero texture for fermion mass matrices in SO(10) model, the neutrino Dirc mass matrix is derived from the up-quark mass matrix. By adjusting two scales of the Majorana mass sector, we can derive…
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…
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 study the structure of the neutrino mass matrix in the minimal gauged U(1)$_{L_\mu-L_\tau}$ model, where three right-handed neutrinos are added to the Standard Model in order to obtain non-zero masses for active neutrinos. Because of the…
We propose a model where neutrino masses are generated at three loop order but neutrinoless double beta decay occurs at one loop. Thus we can have large neutrinoless double beta decay observable in the future experiments even when the…
A candidate for the simple empirical neutrino mass formula is found, predicting the mass proportion m_1:m_2:m_3 = 0:4:24 and so, the mass ratio Delta m^2_{32}/Delta m^2_{21} = 35 not inconsistent with its experimental estimate. It involves…
We propose two new simple lepton flavor models in the framework of the $S_4$ flavor symmetry. The neutrino mass matrices, which are given by two complex parameters, lead to the inverted mass hierarchy. The charged lepton mass matrix has the…
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…
We study natural lepton mass matrices, obtained assuming the stability of physical flavour observables with respect to the variations of individual matrix elements. We identify all four possible stable neutrino textures from algebraic…
On the basis of the so-called "yukawaon" model, we found out a special form of the neutrino mass matrix $M_\nu$ which gives reasonable predictions. The $M_\nu$ is given by a multiplication form made of charged lepton mass matrix $M_e$ and…
We note that the emerging features of lepton mixing can be reproduced if, with inverted neutrino mass ordering, both the smallest neutrino mass and the $\tau\tau$ element of the neutrino mass matrix vanish. Then, the atmospheric neutrino…
A two-parameter neutrino mass formula is described, giving a moderately hierarchical spectrum m_1 < m_2 < m_3 consistent with the experimental estimates of Delta m^2_{21} and Delta m^2_{32}. The formula follows from a three-parameter…
We consider phenomenologically allowed structures of the neutrino mass matrix in the case of three light neutrino species. Constraints from the solar, atmospheric and reactor neutrino experiments as well as those from the neutrinoless…
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…
Under the assumption that the neutrinos are Majorana particles we study how the lepton mass matrices can be transformed into the simple form which has the same physical quantities by removing redundant parameters. We propose the exact…
General Majorana neutrino mass matrix is complex symmetric and for three generations of neutrinos it contains 12 real parameters. We diagonalize this general neutrino mass matrix and express the three neutrino masses, three mixing angles,…