Heavy Higgs of the Twin Higgs Models

Abstract: Twin Higgs models are the prime illustration of neutral naturalness, where the new particles of the twin sector, gauge singlets of the Standard Model (SM), ameliorate the little hierarchy problem. In this work, we analyse phenomenological implications of the heavy Higgs of the Mirror Twin Higgs and Fraternal Twin Higgs models, when electroweak symmetry breaking is linearly realized. The most general structure of twin Higgs symmetry breaking, including explicit soft and hard breaking terms in the scalar potential, is employed. The direct and indirect searches at the LHC are used to probe the parameter space of Twin Higgs models through mixing of the heavy Higgs with the SM Higgs and decays of the heavy Higgs to the SM states. Moreover, for the Fraternal Twin Higgs, we study the production and decays of twin glueball and bottomonium states to the SM light fermions, which have interesting signatures involving displaced vertices and are potentially observable at the colliders.