A composite Higgs with a heavy composite axion
Tony Gherghetta, Minh D. Nguyen
Abstract
A bstract We consider the strong dynamics associated with a composite Higgs model that simultaneously produces dynamical axions and solves the strong CP problem. The strong dynamics arises from a new Sp or SU(4) hypercolor gauge group containing QCD colored hyperfermions that confines at a high scale. The hypercolor global symmetry is weakly gauged by the Standard Model electroweak gauge group and an enlarged color group, SU( N + 3) × SU( N ) ′ . When hyperfermion condensates form, they not only lead to an SU(5)/SO(5) composite Higgs model but also spontaneously break the enlarged color group to SU(3) c × SU( N ) D . At lower energies, the SU( N ) D group confines, producing two dynamical axions that eliminates all CP violation. Furthermore, small instantons from the SU( N ) ′ group can enhance the axion mass, giving rise to TeV scale axion masses that can be detected at collider experiments. Our model provides a way to unify the composite Higgs with dynamical axions, without introducing new elementary scalar fields, while also extending the range of axion masses that addresses the strong CP problem.