A Simple Model of Gauged Lepton and Baryon Charges

Abstract

We propose a simple extension of the standard model with lepton and baryon numbers gauged by introducing only two leptoquarks (j^+1/2, k^-1/2) to the fermion content. As natural consequences of the anomaly cancelation, the right-handed neutrinos present and the number of observed fermion families equals to the number of fundamental colors, which is three. To avoid stabilized colored-leptoquarks, two scalar doublets Φ, χ are introduced which couple the leptoquarks to ordinary quarks. The new gauge bosons 'Z_L, 'Z_B gain masses via the vacuum values of scalars S_L, S_B which are only charged under the U(1)_L, U(1)_B symmetries, respectively. Furthermore, due to the spontaneous symmetry breaking of these charges, the neutrinos obtain small masses via type I seesaw mechanism while the baryogenesis can be generated in several cases. Constraints coming from flavor changing, stabilization of anomalously electriccharged scalars and collision phenomenology are also obtained.