Related papers: Interplay between $\mu$-$\tau$ reflection symmetry…

We discuss consequences of assuming ($i$) that the (Majorana) neutrino mass matrix $M_\nu$ displays flavour antisymmetry, $S_\nu^T M_\nu S_\nu=-M_\nu$ with respect to some discrete symmetry $S_\nu$ contained in $SU(3)$ and ($ii$) $S_\nu$…

Working within the context of texture-zeros mechanism for fermionic mass matrices, we provide necessary and sufficient conditions on the characteristic polynomial coefficients such that it has real, simple and positive roots. We translate…

The even weight modular forms of level $N$ can be arranged into the common irreducible representations of the inhomogeneous finite modular group $\Gamma_N$ and the homogeneous finite modular group $\Gamma'_N$ which is the double covering of…

Texture zeroes in neutrino mass matrix $M_\nu$ may give us hints about the symmetries involved in neutrino mass generation. We examine the viability of such texture zeroes in a model independent way through a bottom-up approach. Using…

We consider a supersymmetric SO(10) model with a SU(3) symmetry of flavour in which fermion masses emerge via the see-saw mixing with superheavy fermions in 16+16bar representations. In this model the dangerous D=5 operators of proton decay…

We consider the flavor symmetry L_mu - L_tau for the neutrino mass matrix. The most general neutrino mass matrix conserving L_mu - L_tau predicts quasi-degenerate neutrino masses with one maximal and two zero mixing angles. The presence of…

In this paper, we generally analyze the $\mu - \tau$ reflection symmetry modified by small mixings of charged leptons and how will future experiments verify deviations from the predictions of the symmetry. As an approximation, the…

Texture zeros in the quark Yukawa matrices generally lead to precise and simple expressions for CKM matrix elements in terms of ratios of quark masses. Using the new data on $b-$decays we test a particularly promising texture zero solution…

An effective texture is presented for six Majorana neutrinos, three active and three (conventional) sterile, based on a 6x6 mass matrix, whose 3x3 active--sterile component (i.e., Dirac component) is conjectured to get a fermion universal…

The charged fermion masses of the three generations exhibit the two strong hierarchies m_3 >> m_2 >> m_1. We assume that also neutrino masses satisfy m_{nu 3} > m_{nu 2} > m_{nu 1} and derive the consequences of the hierarchical spectra on…

I investigate viable textures with two texture zeros for the inverted neutrino mass matrix, and present the predictions of those textures for the neutrino masses and for lepton mixing. By using an Abelian symmetry and one or two heavy…

We propose and study a common hierarchical mass texture for both charged lepton and neutrino sectors. The texture gives rise to a large $\nu_\mu\leftrightarrow\nu_\tau$ mixing. Also it leads to the small angle MSW effect solution for solar…

The current study aimed to investigate the special case of two zeros in a Majorana neutrino mass matrix based on $A_4$ symmetry, where charged lepton mass matrix is diagonal. The texture $M_\nu^{S_7}$ with $(\mu, \mu)$ and $(\tau,\tau)$…

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 $M_F$ is…

It was recently shown by the authors that the Fritzsch ansatz for the quark mass matrices prescribed at the supersymmetric grand unified scale is compatible with a moderately heavy top quark ($m_t \simeq 120-150~GeV$). Here we extend the…

A unified framework sheltering the type-I Dirac seesaw, based on the $\Delta(27) \times Z_7 \times Z_{5} \times Z_4 \times Z_3$ symmetry, is proposed, preserving the naturalness of Yukawa couplings. It helps to visualize mass matrices…

The observed pattern of lepton flavor mixing and CP violation strongly indicates the possible existence of a simple flavor symmetry in the neutrino sector -- the effective Majorana neutrino mass term keeps invariant when the three…

The exchange symmetry between the muon neutrino and the tau neutrino for the neutrino mass matrix has been very useful in understanding the near maximal atmospheric neutrino mixing angle. However, this symmetry can not be imposed at the…

I report low energy results on the study of fermion masses and mixing for quarks and leptons, including neutrinos within a SU(3) flavor symmetry model, where ordinary heavy fermions, top and bottom quarks and tau lepton become massive at…

The recent evidence for neutrino oscillations stimulate us to discuss again the problem of fermion masses and mixings in gauge theories. In the standard model, several forms for quark mass matrices are equivalent. They become ansatze within…