CMS-PAS-TOP-24-003

CMS-PAS-TOP-24-003
Measurement of the $ \mathrm{t}\bar{\mathrm{t}}\mathrm{W} $ differential cross section and charge asymmetry at $ \sqrt{s}= $ 13 TeV
CMS Collaboration
22 March 2025

Abstract: Measurements of top quark-antiquark pair production properties in association with a W boson in proton-proton collisions at a center-of-mass energy of 13 TeV are presented, using a data sample corresponding to an integrated luminosity of 138 fb$ ^{-1} $, recorded by the CMS experiment at the CERN LHC. Events are selected based on the presence of either two leptons with the same electric charge or three leptons, and multiple jets and b-tagged jets. Firstly, we present a measurement of the differential production cross section as a function of kinematic variables sensitive to different aspects of this process' modeling, using a multivariate discriminator in the two-lepton selection region and a cut-based method in the three-lepton region. The normalized cross section measurements are generally consistent with the SM expectations, while we observe larger values compared to the expectations in the absolute cross section measurements, consistent with previous inclusive cross section measurements. The measurements in the two-lepton region using the cut-based method are also shown and are found to be consistent with the multivariate discriminator method. In addition, we measure the leptonic charge asymmetry of this process, obtaining an observed value of $ A_c^{\ell}=$ $- $0.19 $ ^{+0.16}_{-0.18} $, consistent with the expectation of $-$0.09 $ ^{+0.12}_{-0.14} $ predicted by next-to-leading order simulations.
Links: CDS record (PDF) ; Physics Briefing ; CADI line (restricted) ; These preliminary results are superseded in this paper, Submitted to JHEP. The superseded preliminary plots can be found here.

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