New theoretical constraints on scalar color octet models

TL;DR

This paper establishes new theoretical constraints on scalar color octet models, including unitarity, stability, and mass splitting limits, using advanced perturbative and renormalization techniques.

Contribution

It provides the first next-to-leading order unitarity constraints and stability conditions for scalar color octet models, expanding the theoretical understanding of these models.

Findings

Derived unitarity bounds at next-to-leading order.

Established stability conditions for the scalar potential.

Set upper limits on scalar mass splittings.

Abstract

We study theoretical constraints on a model whose scalar sector contains one color octet and one or two color singlet $SU(2)_L$ doublets. Using the unitarity of the theory, we constrain the parameters of the scalar potential for the first time at next-to-leading order in perturbation theory. We also derive new conditions guaranteeing the stability of the potential. We use the HEPfit package to single out the viable parameter regions at the electroweak scale and test the stability of the renormalization group evolution up to the multi-TeV region. Additionally, we set upper limits on the scalar mass splittings. All results are given for both cases, with and without a second scalar color singlet.