Simple mass matrices of neutrinos and quarks consistent with observed mixings and masses

Abstract

We propose a simple phenomenological model of quarks-leptons mass matrices having fundamentally universal symmetry structure. These mass matrices consist of democratic and semi-democratic mass matrix terms commonly to the neutrino and the quark sectors and have only eight free parameters. We show that this mass matrix model well reproduces all the observed values of the MNS lepton and the CKM quark mixing angles, the neutrino mass squared difference ratio, and quark mass ratios, with an excellent agreement. The model also predicts $\delta_{CP}^\ell =-94^\circ$ for the leptonic $CP$ violating phase and $\langle m\rangle\simeq 0.0073$ eV for the effective Majorana neutrino mass.