Z0Z0′ and ordinary-exotic fermion mixings revisited using some special observables

Z 0 –Z 0 ′ and ordinary-exotic fermion mixings revisited using some

Fermion masses and mixings in gauge theories

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 most extensions of the standard model, where also relations between quark and lepton sectors may hold. In a seesaw framework, these relations can constrain ...

Fermion mixings vs d = 6 proton decay

It is well known, although sometimes ignored, that not only the d = 5 but also d = 6 proton decay depends on fermion mixings. In general we study carefully the dependence of d = 6 decay on fermion mixings using the effective operator approach. We find that without specifying a theory it is impossible to make clear predictions. Even in a given model, it is often not possible to determine all the...

Fermion Mixings in SU(9) Family Unification

In an SU(9) model of gauged family unification, we propose an explanation for why angles observed in the lepton flavor (PMNS) mixing matrix are significantly larger than those measured for any analagous quark flavor (KM) mixing angle. It is directly related to a see-saw mechanism that we assume to be responsible for the generation of neutrino masses. Our model is more constrained and therefore ...

Family symmetries and the origin of fermion masses and mixings

Family symmetries are possibly the most conservative extension of the Standard Model that attempt explanations of the pattern of fermion masses and mixings. The observed large mixing angles in the lepton sector may be the first signal for the presence of a non-Abelian family symmetry. We investigate the possibilities of simultaneously explaining the observed pattern of masses of the quarks (hie...