Differential cross section measurements of $WW + \ge1$ jets with ATLAS

Fiducial and differential cross-section measurements of $W^+W^-$ production in association with at least one hadronic jet are presented. These measurements are sensitive to the properties of electroweak-boson self-interactions and provide a test of perturbative quantum chromodynamics and the electroweak theory. The analysis is performed using proton-proton collision data collected at $\sqrt{s}=13$ TeV with the ATLAS experiment, corresponding to an integrated luminosity of 139 fb$^{-1}$. Events are selected with exactly one oppositely charged electron-muon pair and at least one hadronic jet with a transverse momentum of $p_{\mathrm{T}}>30$ GeV and a pseudorapidity of $|\eta|<4.5$. After subtracting the background contributions and correcting for detector effects, the jet-inclusive $W^+W^-+\ge 1$ jet fiducial cross-section and $W^+W^-+$ jets differential cross-sections with respect to several kinematic variables are measured. These measurements include leptonic quantities, such as the lepton transverse momenta and the transverse mass of the $W^+W^-$ system, as well as jet-related observables such as the leading jet transverse momentum and the jet multiplicity.