Forward-backward asymmetry in top quark-antiquark production

We present a measurement of forward-backward asymmetry in top quark-antiquark production in proton-antiproton collisions in the final state containing a lepton and at least four jets. Using a data set corresponding to an integrated luminosity of $5.4{\mathrm{fb}}^{-1}$, collected by the D0 experiment at the Fermilab Tevatron Collider, we measure the $t\overline{t}$ forward-backward asymmetry to be $(9.2\pm 3.7)\%$ at the reconstruction level. When corrected for detector acceptance and resolution, the asymmetry is found to be $(19.6\pm 6.5)\%$. We also measure a corrected asymmetry based on the lepton from a top quark decay, found to be $(15.2\pm 4.0)\%$. The results are compared to predictions based on the next-to-leading-order QCD generator mc@nlo. The sensitivity of the measured and predicted asymmetries to the modeling of gluon radiation is discussed.