Charge Asymmetry of Weak Boson Production at the LHC and the Charm Content of the Proton

TL;DR

This paper demonstrates how measurements of weak boson production and their charge asymmetries at the LHC can constrain the proton's parton distribution functions, especially the charm content, using reconstructed leptonic decay data.

Contribution

It introduces a method to use LHC boson rapidity distributions to simultaneously constrain u, d, and charm quark distributions within the proton.

Findings

Charge asymmetry measurements constrain u and d quark distributions.

The W/Z ratio directly probes the charm quark distribution.

Results improve understanding of proton structure at high energies.

Abstract

We investigate the production of the weak bosons $W^+$, $W^-$ and $Z$ at the LHC as a function of their rapidity, reconstructed {\it experimentally} from their leptonic decay. We show that the measurements provide a powerful tool for constraining the parton distribution functions, as was already the case for the lower energy $p\bar{p}$ collider data. We study the charge asymmetry determining the $u$ and $d$ distribution functions using the reconstructed $W^+$, $W^-$ rapidities. We also show how the ratio of the $W$ and $Z$ boson rapidity distributions directly probes the charm quark distribution function of the proton.