title: Electroweak baryogenesis in a supersymmetric U(1)' model.
abstract: We construct an anomaly-free supersymmetric U(1)' model with a secluded U(1)'-breaking sector. We study the one-loop effective potential at finite temperature and show that there exists a strong enough first order electroweak phase transition for electroweak baryogenesis (EWBG) because of the large trilinear term AhhSHdHu in the tree-level Higgs potential. Unlike in the minimal supersymmetric standard model, the lightest top squark can be very heavy. We consider the nonlocal EWBG mechanism in the thin wall regime and find that within uncertainties the observed baryon number can be generated from the tau lepton contribution, with the secluded sector playing an essential role. The chargino and neutralino contributions and the implications for the Z' mass and electric dipole moments are briefly discussed.
authors.affiliation: Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6396, USA.
authors.forename: Junhai
authors.initials: J
authors.lastname: Kang
authors.forename: Paul
authors.initials: P
authors.lastname: Langacker
authors.forename: Tianjun
authors.initials: T
authors.lastname: Li
authors.forename: Tao
authors.initials: T
authors.lastname: Liu