Non-exotic $Z'$ signals in $\ell^+\ell^-$, $b\bar b$ and $t\bar t$ final states at the LHC

TL;DR

This paper investigates how different final states at the LHC can be used to determine the properties of a non-exotic $Z'$ boson, emphasizing the importance of combining multiple channels for full characterization.

Contribution

It provides a comprehensive analysis of di-lepton and di-quark channels to profile a non-exotic $Z'$ at the LHC, highlighting the necessity of combined channel analysis for complete parameter space coverage.

Findings

Multiple channels improve $Z'$ quantum number determination.

Interference effects and backgrounds are significant in analysis.

Combined channel approach enhances sensitivity across models.

Abstract

In the attempt to fully profile a $Z'$ boson accessible at the Large Hadron Collider (LHC), we study the sensitivity of di-lepton (for the electron, muon and tauon cases) and di-quark (for the case of the heavy flavours, $t$ and, possibly, $b$) samples to the nature of the new gauge state, for a one-dimensional class of non-exotic $Z'$ bosons. Assuming realistic final state reconstruction efficiencies and error estimates, we find that, depending on the CERN collider energy and luminosity, the best chances of extracting the $Z'$ quantum numbers occur when two or more of these channels are simultaneously explored, as none of them separately enables one to fully probe the parameter spaces of the aforementioned models. Effects of Standard Model (SM) background as well interferences between this and the various $Z'$ signals have been accounted for. A complete study of cross sections and asymmetries (both spatial and spin ones) makes clear the need for complementarity, especially for their disentanglement over the full parameter space.