G221 Interpretations of the Diboson and Wh Excesses

Abstract

Based on an $SU(2) \times SU(2) \times U(1)$ effective theory framework (aka $G221$ models), we investigate a leptophobic $SU(2)_L \times SU(2)_R \times U(1)_{B-L}$ model, in which the right-handed $W^\prime$ boson has the mass of around 2 TeV, and predominantly couples to the standard model quarks and the gauge-Higgs sector. This model could explain the resonant excesses near 2 TeV reported by the ATLAS collaboration in the $WZ$ production decaying into hadronic final states, and by the CMS collaboration in the $Wh$ channel decaying into $b\bar{b}\ellν$ and dijet final state. After imposing the constraints from the electroweak precision and current LHC data, we find that to explain the three excesses in $WZ$, $Wh$ and dijet channels, the $SU(2)_R$ coupling strength $g_R$ favors the range of $0.47 \sim 0.68$. In this model, given a benchmark 2 TeV $W'$ mass, the $Z'$ mass is predicted to be around $2.9$ TeV if the doublet Higgs (LPD) is used to break the G221 symmetry, consistent with the 2.9 TeV $e^+e^-$ event recently observed at CMS. A $3 \sim 5$ TeV mass is typically predicted for the triplet Higgs (LPT) symmetry breaking scenario, can also be consistent with a 2.9 TeV dilepton signal. These signatures can be further explored by the LHC Run-2 data.

16 pages, 6 figures, revised version 2. With a 2.9 TeV Z' event observed in CMS, we updated our paper by discussing the possible 2.9 TeV Z' signature together with the 2 TeV W' excess