Using leptons $p_T$ measurements to constrain $Z^\prime$-bosons widths in Drell-Yan processes at the LHC

TL;DR

The paper introduces a new method using leptons' transverse momentum distributions and a Focus Point asymmetry to constrain the width of hypothetical $Z'$ bosons in Drell-Yan processes at the LHC.

Contribution

It proposes the Focus Point Asymmetry ($A_{FP}$) as a novel observable for constraining $Z'$ boson widths, based on the properties of the Focus Point in lepton $p_T$ distributions.

Findings

The Focus Point appears consistently in lepton $p_T$ distributions from $Z'$ decays.

$A_{FP}$ can effectively constrain $Z'$ widths across various models.

The method enhances sensitivity to $Z'$ properties in collider data.

Abstract

We recognise the appearance of a Focus Point (FP) in the transverse momentum distribution of either leptons originating from a BSM $Z^\prime$-boson decay, after a simple normalisation procedure. Exploring the properties of the FP we will be able to define in a general way a new observable, the Focus Point Asymmetry ($A_{\rm FP}$), which can be used to set constrains on the $Z^\prime$ width. We discuss the potential and the sensitivity of the $A_{\rm FP}$ in as diagnostic tool for $Z^\prime$ physics, considering various $Z^\prime$ phenomenological realisations.