On the Origin of Neutrino Masses

TL;DR

This paper explores simple, renormalizable models for neutrino mass generation at tree and one-loop levels, introducing minimal new particles and discussing experimental implications.

Contribution

It identifies new one-loop neutrino mass models using only two new particle types with automatic baryon number conservation.

Findings

Neutrino masses can be generated with minimal new particles.

Models include scalar and fermionic color octets compatible with experiments.

Potential signals at the LHC are discussed.

Abstract

We discuss the simplest mechanisms for generating neutrino masses at tree level and one loop level. We find a significant number of new possibilities where one can generate neutrino masses at the one-loop level by adding only two new types of representations. These models have renormalizable interactions that automatically conserve baryon number. Adding to the minimal standard model a scalar color octet with SU(3) X SU(2) X U(1) quantum numbers, (8,2,1/2), and a fermionic color octet in the fundamental or adjoint representation of SU(2) one can generate neutrino masses in agreement with the experiment. Signals at the LHC, and constraints from flavour violation are briefly discussed.