Heavy $Z^\prime$ Bosons in the Secluded $U(1)^\prime$ Model at Hadron Colliders

TL;DR

This paper investigates the potential for discovering heavy $Z'$ bosons in a $U(1)'$ extended MSSM with a secluded sector at future high-energy hadron colliders, analyzing production, decay channels, and experimental prospects.

Contribution

It introduces a $U(1)'$ model with a secluded sector and performs detailed collider phenomenology analysis for $Z'$ bosons with masses 4-5.2 TeV, including decay modes into supersymmetric particles.

Findings

Discovery likelihood is low at HL-LHC (14 TeV).

Higher energy colliders (27 and 100 TeV) have better prospects.

Specific benchmark scenarios could enable $Z'$ detection at future colliders.

Abstract

We study $Z'$ phenomenology at hadron colliders in an $U(1)'$ extended MSSM. We choose a $U(1)'$ model with a secluded sector, where the tension between the electroweak scale and developing a large enough mass for $Z'$ is resolved by incorporating three additional singlet superfields into the model. We perform a detailed analysis of the production, followed by decays, including into supersymmetric particles, of a $Z'$ boson with mass between 4 and 5.2 TeV, with particular emphasis on its possible discovery. We select three different scenarios consistent with the latest available experimental data and relic density constraints, and concentrate on final signals with two leptons, four leptons and six leptons. Including the SM background from processes with two, three or four vector bosons, we show the likelihood of observing a $Z^\prime$ boson is not promising for the HL-LHC at 14 TeV. While at 27 and 100 TeV, the situation is more optimistic, and we devise specific benchmark scenarios which could be observed.