Evading Z′ boson mass limits in U(1)′ supersymmetric models

Abstract

Supersymmetric models augmented by U(1)′ gauge symmetries resolve some of the outstanding problems in MSSM, such as the μ problem. Unfortunately collider phenomenology in such models is hindered by the stringent limits from the ATLAS and CMS collaborations on the Z′ boson mass. We explore possibilities of lowering the mass in either leptophobic models, by employing kinetic mixing, or in models with non-universal U(1)′ charges, where the Z′ boson does not couple either to the first two generation quarks, thus lowering its production cross-section, or to the first two generation leptons, thus lowering its di-lepton branching ratio. We verify consistency of these models with dark matter bounds and indicate the most promising signals at the collider.