Measurements of differential cross-sections of $WbWb$ production in the dilepton channel in $pp$ collisions at $\sqrt{s}$ = 13 TeV using the ATLAS detector

TL;DR

This paper presents detailed measurements of the differential cross-sections for $WbWb$ production in proton-proton collisions at 13 TeV, using ATLAS data, to improve understanding of top quark processes and QCD modeling.

Contribution

First measurement of $WbWb$ differential cross-sections at 13 TeV in the dilepton channel, providing new data to test and refine theoretical models and simulations.

Findings

Results agree with NLO Monte Carlo predictions within uncertainties.

Provides constraints on $WbWb$ production modeling and interference effects.

Enhances understanding of top quark pair and single-top production processes.

Abstract

At the Large Hadron Collider, the $WbWb$ final state is expected to be dominated by $t\bar{t}$ production with a contribution from single-top processes. Differential cross-sections for $WbWb$ production in the dilepton decay channel are measured at the particle level as a function of various kinematic variables. The analysis is based on data from proton-proton collisions at a centre-of-mass energy of $\sqrt{s} = 13$ TeV, recorded by the ATLAS detector at the Large Hadron Collider over the period from 2015 to 2018, corresponding to an integrated luminosity of 140 fb$^{-1}$. Measurements are performed within the fiducial phase-space defined by the presence of two $b$-jets and one electron and one muon of opposite charges. The differential cross-sections are corrected for detector effects and unfolded to the particle level. Results are compared with predictions from Monte Carlo event generators at next-to-leading order in perturbative quantum chromodynamics. These measurements provide valuable constraints on the modelling of $WbWb$ production and the interference between doubly resonant and singly resonant $WbWb$ production.