Two Higgs doublet models augmented by a scalar color octet

TL;DR

This paper investigates how adding a scalar color octet to two Higgs doublet models affects Higgs couplings to gluons and photons, using LHC data to constrain the model and explore new physics possibilities.

Contribution

It extends 2HDM analyses by including one-loop Higgs couplings to gluons and photons with a scalar color octet, providing new constraints from LHC measurements.

Findings

Constraints on the scalar color octet from Higgs coupling measurements

Theoretical bounds on the augmented 2HDM parameter space

Implications for new colored particles in Higgs physics

Abstract

The LHC is now studying in detail the couplings of the Higgs boson in order to determine if there is new physics. Many recent studies have examined the available fits to Higgs couplings from the perspective of constraining two Higgs doublet models (2HDM). In this paper we extend those studies to include constraints on the one loop couplings of the Higgs to gluons and photons. These couplings are particularly sensitive to the existence of new colored particles that are hard to detect otherwise and we use them to constrain a 2HDM augmented with a color-octet scalar, a possibility motivated by minimal flavor violation. We first study theoretical constraints on this model and then compare them with LHC measurements.