CERN Accelerating science

ATLAS Note
Report number	ATLAS-CONF-2023-012
Title	Measurements of $W^+W^-$ production cross sections in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
Corporate Author(s)	The ATLAS collaboration
Collaboration	ATLAS Collaboration
Publication	2023
Imprint	31 Mar 2023
Number of pages	37
Note	All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/CONFNOTES/ATLAS-CONF-2023-012
In:	57th Rencontres de Moriond on Electroweak Interactions and Unified Theories, La Thuile, It, 18 - 25 Mar 2023
Subject category	Particle Physics - Experiment
Accelerator/Facility, Experiment	CERN LHC ; ATLAS
Abstract	Measurements of $W^+W^-\rightarrow e^\pm \nu \mu^\mp \nu$ production cross-sections are presented, providing a test of the predictions of perturbative quantum chromodynamics, parton distribution functions, and the electroweak theory. The measurements are performed using $pp$ collision data recorded by the ATLAS detector at the Large Hadron Collider in 2015-2018 at $\sqrt{s}=13$ TeV, corresponding to an integrated luminosity of 140 fb$^{-1}$. The number of events due to top-quark pair production, the largest background, is reduced by rejecting events containing jets with $b$-hadron decays. An improved methodology of estimating the remaining top quark background enables a precise measurement of $W^+W^-$ cross-sections with no additional requirements on jets. The fiducial $W^+W^-$ cross section is determined in a maximum-likelihood fit with an uncertainty of 3.1%. The measurement is extrapolated to the full phase space, resulting in a total $W^+W^-$ cross-section of $127\pm4$ pb. Differential cross-sections are measured as a function of twelve observables that comprehensively describe the kinematics of $W^+W^-$ events. The measurements are compared to state-of-the art theory calculations and excellent agreement with predictions is observed.

Corresponding record in: Inspire