G221 Interpretations of the Diboson and Wh Excesses

TL;DR

This paper explores a leptophobic G221 model with a 2 TeV W' boson to explain recent diboson and associated excesses observed at the LHC, predicting correlated Z' signals and Higgs sector implications.

Contribution

It introduces a specific G221 model that accounts for multiple LHC excesses and predicts related new particles and signals consistent with current constraints.

Findings

W' boson mass around 2 TeV explains excesses in WZ, Wh, and dijet channels.

Predicted Z' mass around 2.9 TeV correlates with recent CMS dilepton events.

Model parameters constrained by electroweak precision and LHC data.

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 $b\bar{b}\ell\nu$ 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.