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تسجيل مستخدم جديدThe top quark charge asymmetry in $tbar{t}gamma$ production at the LHC
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We consider the top quark charge asymmetry in the process $pp to tbar{t}+gamma$ at the 13 TeV LHC. The genuine tree level asymmetry in the $qbar{q}$ channel is large with about -12%. However, the symmetric $gg$ channel, photon radiation off top quark decay products, and higher order corrections wash out the asymmetry and obscure its observability. In this work, we investigate these effects at next-to-leading order QCD and check the robustness of theoretical predictions. We find a sizable perturbative correction and discuss its origins and implications. We also study dedicated cuts for enhancing the asymmetry and show that a measurement is possible with an integrated luminosity of 150 fb$^{-1}$.
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