CERN Accelerating science

ATLAS Slides
Report number	ATL-PHYS-SLIDE-2023-025
Title	Measurement of differential cross-sections of $t\bar{t}$ production in the electron-muon channel with the full Run 2 data set
Author(s)	Martinelli, Luca (Sapienza Universita e INFN, Roma I (IT))
Corporate author(s)	The ATLAS collaboration
Collaboration	ATLAS Collaboration
Submitted to	36th Rencontres de Physique de La Vallée d'Aoste (La Thuile 2023), La Thuile, Aosta, Italy, 5 - 11 Mar 2023
Submitted by	[email protected] on 20 Mar 2023
Subject category	Particle Physics - Experiment
Accelerator/Facility, Experiment	CERN LHC ; ATLAS
Free keywords	Top-quark ; Cross-section ; dilepton channel ; full Run2 ; TOP
Abstract	Measurements of the total and differential top-quark pair-production cross sections in proton proton collisions at 13 TeV with the ATLAS detector at the Large Hadron Collider are presented. The measurements use data collected by ATLAS during the entire LHC Run2 (2015 - 2018) corresponding to an integrated luminosity of 139 fb^-1. The measurements are performed in the di-lepton channel, requiring an opposite-charge high-pt electron-muon pair and b-tagged jets. The experimental uncertainties due to the identification of b-quark jets are constrained in-situ by data. The total cross-section is compared to predictions by theoretical QCD calculations at next-to-next-to-leading order. Absolute and normalised single- and double-differential cross sections are calculated as a function of single-lepton and dilepton kinematic variables, featuring finer granularity and extended kinematic range compared to previous ATLAS measurements. The results are compared with multiple predictions from next-to-leading-order QCD matrix-element generators matched with parton-shower generators.