Abstract
The top anti-top quark production cross-section is measured in the lepton+jets channel using proton–proton collision data at a centre-of-mass energy of s=13 TeV collected with the ATLAS detector at the LHC. The dataset corresponds to an integrated luminosity of 139 fb−1. Events with exactly one charged lepton and four or more jets in the final state, with at least one jet containing b-hadrons, are used to determine the tt¯ production cross-section through a profile-likelihood fit. The inclusive cross-section is measured to be σinc=830±0.4(stat.)±36(syst.)±14(lumi.)pb with a relative uncertainty of 4.6%. The result is consistent with theoretical calculations at next-to-next-to-leading order in perturbative QCD. The fiducial tt¯ cross-section within the experimental acceptance is also measured.
Highlights
The top quark is the heaviest elementary particle in the Standard Model (SM), with a mass mt close to the electroweak symmetry breaking scale [1,2]
The V +jets (V = W, Z ) backgrounds were simulated with the Sherpa v2.2.1 [44] generator using NLO-accurate matrix element (ME) for up to two jets, and MEs accurate to leading order (LO) for up to four jets calculated with the Comix [45] and OpenLoops [46,47] libraries
Measurements of the inclusive and fiducial ttproduction crosssections are performed √in the lepton+jets channel using proton– proton collision data at s = 13 TeV recorded by the ATLAS detector at the Large Hadron Collider (LHC) during 2015–2018, corresponding to an integrated luminosity of 139 fb−1
Summary
The top quark is the heaviest elementary particle in the Standard Model (SM), with a mass mt close to the electroweak symmetry breaking scale [1,2]. This Letter documents measurements of the ttcross-sections in the full phase space (inclusive) and in a phase space defined t√o be close to the experimental measurement range (fiducial) at s = 13 TeV, using the full pp dataset collected during 2015–2018. It targets the lepton+jets ttdecay mode, where one W boson originating from the top quark decays leptonically and the other W boson decays hadronically, i.e. tt → W + W −bb → νqqbb , producing a final state with one high-momentum electron or muon and four jets, two of which are b-quark-initiated jets.. Number of top-quark precision measurements and searches beyond the SM
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
