Electroweak Baryogenesis in a Supersymmetric U(1)' Model

TL;DR

The nonlocal EWBG mechanism in the thin wall regime is considered and it is found that within uncertainties the observed baryon number can be generated from the tau lepton contribution, with the secluded sector playing an essential role.

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 $A_h h S H_d H_u$ in the tree-level Higgs potential. Unlike in the MSSM, the lightest stop can be very heavy. We consider the non-local EWBG mechanism in the thin wall regime, and find that within uncertainties the observed baryon number can be generated from the $τ$ 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.

Figures (2)

• Figure 1: The potential versus the VEV $v$ by connecting the true and false minima where $v\equiv\sqrt{|\langle H_u^0 \rangle|^2+|\langle H_d^0 \rangle|^2}$.
• Figure 2: Baryon asymmetry ($n_B/s$) vs. $\gamma$.