Constraining the $g'_1$ coupling in the minimal $B-L$ Model

TL;DR

This paper combines unitarity and renormalisation group analyses to establish a refined upper bound on the $g'_1$ gauge coupling in the minimal $B-L$ extension of the Standard Model, enhancing previous triviality constraints.

Contribution

It introduces a novel method that uses perturbative unitarity and RG evolution to more precisely constrain the $g'_1$ coupling in the minimal $B-L$ model.

Findings

Perturbative unitarity imposes an upper bound on $g'_1$.

The method refines triviality bounds on the coupling.

Analysis of vector boson and scalar scattering amplitudes.

Abstract

We have combined the perturbative unitarity and the renormalisation group equations arguments in order to find a dynamical way to constrain the $g'_1$ coupling of the minimal $B-L$ extension of the Standard Model. We have analysed the role of the $g'_1$ coupling evolution in the perturbative stability of the two-to-two body scattering amplitudes of the vector boson and scalar sectors of the model and we have shown that the perturbative unitarity imposes an upper bound on the $B-L$ gauge coupling. We have made a comparison between this criterion and the triviality arguments, showing that our procedure substantially refines the triviality bounds.