Observation of electroweak W$^+$W$^-$ pair production in association with two jets in proton-proton collisions at $\sqrt{s}$ = 13 TeV

TL;DR

This paper reports the first observation of electroweak W$^+$W$^-$ pair production with two jets at the LHC, confirming the Standard Model prediction with high significance.

Contribution

It provides the first experimental observation of electroweak W$^+$W$^-$ production in association with two jets at 13 TeV, with precise cross section measurement.

Findings

Observation with 5.6 sigma significance

Measured cross section of 10.2 ± 2.0 fb

Consistent with Standard Model prediction

Abstract

An observation is reported of the electroweak production of a W$^+$W$^-$ pair in association with two jets, with both W bosons decaying leptonically. The data sample corresponds to an integrated luminosity of 138 fb$^{-1}$ of proton-proton collisions at $\sqrt{s}$ = 13 TeV, collected by the CMS detector at the CERN LHC. Events are selected by requiring exactly two opposite-sign leptons (electrons or muons) and two jets with large pseudorapidity separation and high dijet invariant mass. Events are categorized based on the flavor of the final-state leptons. A signal is observed with a significance of 5.6 standard deviations (5.2 expected) with respect to the background-only hypothesis. The measured fiducial cross section is 10.2 $\pm$ 2.0 fb and this value is consistent with the standard model prediction of 9.1 $\pm$ 0.6 fb.