| ATLAS Note | |
| Report number | ATLAS-CONF-2019-026 |
| Title | Inclusive and differential measurement of the charge asymmetry in $t\bar{t}$ events at 13 TeV with the ATLAS detector |
| Corporate Author(s) | The ATLAS collaboration |
| Collaboration | ATLAS Collaboration |
| Publication | 2019 |
| Imprint | 11 Jul 2019 |
| Number of pages | mult. |
| Note | All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/CONFNOTES/ATLAS-CONF-2019-026 |
| Subject category | Particle Physics - Experiment |
| Accelerator/Facility, Experiment | CERN LHC ; ATLAS |
| Free keywords | 13 TeV ; 1 lepton ; Boosted ; Differential measurement ; EFT ; ttbar asymmetry measurements ; Top properties measurements |
| Abstract | A measurement of the top-antitop ($t\bar t$) charge asymmetry $A_{\text{C}}$ is presented using data corresponding to an integrated luminosity of 139 fb$^{-1}$ of $\sqrt{s} = 13$ TeV of $pp$ collisions recorded by the ATLAS experiment at the Large Hadron Collider, CERN. The measurement is performed in the single-lepton channel ($e$ or $\mu$) combining both the resolved and boosted topologies of top quark decays. A Bayesian unfolding procedure is used to infer the asymmetry at parton level, correcting for detector resolution and acceptance effects. The inclusive $t\bar t$ charge asymmetry is measured as $A_{\text{C}} = 0.0060 \pm 0.0015 \textrm{(stat+syst.)}$, which differs from zero by 4 standard deviations. Differential measurements are performed as a function of the invariant mass and longitudinal boost of the $t\bar t$ system. Both inclusive and differential measurements are found to be compatible with the Standard Model predictions, at NNLO in perturbation theory with NLO electroweak corrections. |
| Related document | superseded by: CERN-EP-2022-166 |
Corresponding record in: Inspire
Record created 2019-07-11, last modified 2022-08-26
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