Polarisation of electroweak gauge bosons at the LHC

TL;DR

This paper analyzes the polarization states of electroweak gauge bosons produced at the LHC, revealing how different production processes influence polarization and its observable effects in decay distributions.

Contribution

It provides a comprehensive study of gauge boson polarization across various LHC processes, including W+jets, top production, and Z+jets, highlighting process-dependent polarization patterns.

Findings

Polarization affects angular and momentum distributions of decay leptons.

Different processes produce distinct polarization states.

Polarization patterns reflect underlying scattering dynamics.

Abstract

We present results for the polarisation of gauge bosons produced at the LHC. Polarisation effects for W bosons manifest themselves in the angular distributions of the lepton and in the distributions of lepton transverse momentum and missing transverse energy. The polarisation is discussed for a range of different processes producing W bosons such as W+jets and W from top production. The relative contributions of the different polarisation states vary from process to process, reflecting the dynamics of the underlying hard-scattering process. We also calculate the polarisation of the Z boson produced in association with QCD jets at the LHC.