W Boson Production with Associated Jets at Large Rapidities

TL;DR

This work analyzes W boson production in association with one or two jets at hadron colliders in both exact LO kinematics and the high-energy limit, emphasizing forward-W configurations as a natural setting for BFKL resummation. It develops the high-energy factorization framework, deriving LO jet and W+jet impact factors and formulating the W+2-jet cross section within the BFKL ladder, implemented via a Monte Carlo that preserves energy-momentum constraints. The study shows that forward-W topologies are enhanced by parton distributions and gluon exchange in the crossed channel, and it demonstrates observable signatures of BFKL dynamics—such as the Δy dependence, azimuthal decorrelation, and mean jet multiplicity—in W+jets. These results provide a concrete pathway to probe high-energy QCD at the LHC using W+jets final states and guide the construction of LL-accurate, energy-m conserving resummation tools.

Abstract

We analyse W boson production at hadron colliders in association with one or two jets, both with the exact kinematics and in the high-energy limit. We argue that the configurations that are kinematically favoured tend to have the W boson forward in rapidity. Thus W boson production in association with jets lends itself naturally to extensions to the high-energy limit, which we examine both at leading order and by resumming higher-order corrections through the BFKL theory.

Figures (12)

• Figure 1: Rapidity distributions of the $W$ boson for the subprocesses $(a)$$q\, g\to W\, q$ and $(b)$$q\, \bar{q}\to W\, g$ at the LHC centre-of-mass energy $\sqrt{s} =$ 14 TeV and with $p_{j_\perp{\rm min}} =$ 30 GeV.
• Figure 2: Rapidity distributions of the jet for the subprocesses $(a)$$q\, g\to W\, q$ and $(b)$$q\, \bar{q}\to W\, g$ at the LHC centre-of-mass energy $\sqrt{s} =$ 14 TeV and with $p_{j_\perp{\rm min}} =$ 30 GeV.
• Figure 3: Distributions in $y_{ W}$ for the subprocesses of Eq. (\ref{['subpro']}) at the LHC centre-of-mass energy $\sqrt{s} =$ 14 TeV and with $p_{j_\perp{\rm min}}=$ 30 GeV.
• Figure 4: Distributions in $y_{j_2}$, where $j_2$ is the jet that is closest to the $W$, for the subprocesses of Eq. (\ref{['subpro']}) at the LHC centre-of-mass energy $\sqrt{s} =$ 14 TeV and with $p_{j_\perp{\rm min}} =$ 30 GeV.
• Figure 5: Distributions in $y_{j_1}-y_{j_2}$ for the subprocesses of Eq. (\ref{['subpro']}) at the LHC centre-of-mass energy $\sqrt{s} =$ 14 TeV and with $p_{j_\perp{\rm min}} =$ 30 GeV.