Left-right symmetric theory with light sterile neutrinos

A simple theoretical framework for the spontaneous breaking of parity, and baryon and lepton numbers is proposed. In this context, the baryon and lepton numbers are independent local gauge symmetries, while parity is defined making use of the left-right symmetry. We show that in the minimal model the new leptoquark fields needed to define an anomaly-free theory also generate neutrino masses through the type III seesaw mechanism. The spectrum of neutrinos and some phenomenological aspects are discussed. This theory predicts the possible existence of two light sterile neutrinos.

Figure 1

Type III seesaw mechanism for the left-handed neutrinos.

Figure 2

Type III seesaw mechanism for the right-handed neutrinos.