Narrow Results

In this brief report, apart from the usual approach, we discriminate among models in the class of SU(4)_L ⊗ U(1)_Y electroweak gauge models by just setting the versors in the general method of treating gauge models with high symmetries. We prove that the method itself naturally predicts the correct assignment of the electric charge spectrum along with the relation between the gauge couplings of the groups involved therein for each particular model in this class.

The boson mass spectrum of the electroweak SU(4)_L ⊗ U(1)_Y model with exotic electric charges is investigated by using the algebraical approach supplied by the method of solving gauge models with high symmetries. Our approach predicts for the boson sector a one-parameter mass scale to be tuned in order to match the data obtained at LHC, LEP, CDF.

The weak currents with respect to the diagonal neutral bosons Z, Z′ and Z^′′ of a specific SU(4)_L⊗U(1)_Y gauge model are computed in detail for all the fermion families involved therein. Our algebraical approach, which is based on the general method of solving gauge models with high symmetries proposed several years ago by Cotăescu, recovers in a nontrivial way all the Standard Model values for current couplings of the traditional leptons and quarks, and predicts plausible values for those of the exotic fermions in the model.

In this paper we show that the canonical seesaw mechanism can naturally be implemented in a particular class of electroweak SU(4)_L ⊗ U(1)_Y gauge models. The resulting neutrino mass spectrum is determined by just tuning a unique free parameter a within the algebraical method of treating gauge models with high symmetries proposed several years ago by Cotăescu. All the Standard Model phenomenology is preserved, being unaffected by the new physics occurring at a high breaking scale m ~ 10¹¹GeV.

For the particular class of SU(4)_L ⊗ U(1)_Y electroweak models without exotic electric charges, some plausible phenomenological predictions — such as the boson mass spectrum and charges of all the fermions involved therein — are made by using the algebraical approach of the exactly solving method for gauge models with high symmetries. Along with the one-parameter resulting mass scale (to be confirmed at TeV scale in LHC) our approach predicts the exact expressions of the charges (both electric and neutral) in the fermion sector, while all the Standard Model phenomenology is naturally recovered.