Higgs Uncovering Light Scalar Remnants of High Scale Matter Unification

TL;DR

This paper explores how specific colored scalar particles can explain the Higgs to gamma gamma excess, predicts related effects, and connects these particles to matter unification models with implications for proton decay.

Contribution

It identifies particular scalar states compatible with experimental data, predicts correlated Higgs decay effects, and links these states to grand unified theories with testable proton decay signatures.

Findings

Colored scalars (8,2,1/2) and (6,3,1/3) fit the Higgs to gamma gamma excess.

Predicted effects in h to Z gamma and di-Higgs production.

Models relate scalar masses to proton decay lifetimes.

Abstract

We consider the impact of colored scalars that can couple directly to matter fields on the recently measured h to gamma gamma excess. Among all possible candidates only scalar states transforming as (8, 2,1/2) and (6,3,1/3) under the Standard Model gauge group can individually accommodate the excess and remain in agreement with all available data. Current experimental constraints require such colored states to have an order one coupling to the Standard Model Higgs and a mass below 300 GeV. We use the best fit values to predict the correlated effect in h to Z gamma and di-Higgs production. We furthermore discuss where and how these states appear in extensions of the Standard Model with primary focus on scenarios of matter unification. We revisit two simple SU(5) setups to show that these two full-fledged models not only accommodate a light color octet state but correlate its mass with observable partial proton decay lifetimes.