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arXiv · 1709.04207

Direct top-quark decay width measurement in the $t\bar{t}$ lepton+jets channel at $\sqrt{s}$=8 TeV with the ATLAS experiment

ATLAS Collaboration
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Abstract

This paper presents a direct measurement of the decay width of the top quark using $t\bar{t}$ events in the lepton+jets final state. The data sample was collected by the ATLAS detector at the LHC in proton-proton collisions at a centre-of-mass energy of 8 TeV and corresponds to an integrated luminosity of 20.2 fb$^{-1}$. The decay width of the top quark is measured using a template fit to distributions of kinematic observables associated with the hadronically and semileptonically decaying top quarks. The result, $Γ_t = 1.76 \pm 0.33 (\rm{stat.}) ^{+0.79}_{-0.68} (\rm{syst.})\; \rm{GeV}$ for a top-quark mass of 172.5 GeV, is consistent with the prediction of the Standard Model.

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ATLAS Collaboration. 2018-02-22. Direct top-quark decay width measurement in the $t\bar{t}$ lepton+jets channel at $\sqrt{s}$=8 TeV with the ATLAS experiment. https://doi.org/10.1140/epjc%2Fs10052-018-5595-5

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