The leptonic $W^{\pm}$ boson asymmetry in association with jets at LHCb, and PDF constraints at large-$x$

TL;DR

This paper explores how LHCb's forward acceptance enables precise measurements of W boson asymmetries with jets at 14 TeV, significantly reducing uncertainties in the d quark PDF at large Bjorken x.

Contribution

It demonstrates the feasibility of using LHCb data to measure W boson asymmetries and constrains the d quark PDF at high x, a region less accessible to other experiments.

Findings

Leptonic asymmetry measurements can reduce d quark PDF uncertainty by a factor of three.

LHCb's forward acceptance allows probing large-x PDFs beyond ATLAS and CMS capabilities.

Feasibility of W+jets measurements at 14 TeV LHCb is established.

Abstract

The unique forward LHCb acceptance opens the possibility for performing precision Standard Model (SM) processes in a kinematical regime beyond the reach of both ATLAS and CMS experiments. In this article we discuss the feasibility of performing $W^{\pm}j$ measurements with 14 TeV LHCb data, and find that the leptonic asymmetry at high pseudorapidity, with appropriate cuts on the associated jet, can provide a factor of three reduction on the $d$ quark PDF uncertainty in a region of Bjorken $x > 0.5$.