Measurement of the fraction of top quark pair events produced via gluon-gluon fusion at the Tevatron in lepton+jets final states

Abstract

We report a measurement of the fraction of top quark pair events produced via gluon-gluon fusion in $p\bar{p}$ collisions at $\sqrt{s}=1.96\mathrm{TeV}$ in lepton+jets final states using the full RunII data set corresponding to $9.7\mathrm{f}{\mathrm{b}}^{-1}$ of integrated luminosity collected by the DØ experiment. We utilize a boosted decision tree to distinguish top quark pair events produced by $q\bar{q}$ annihilation and $gg$ fusion. We perform a template fit to extract the $t\bar{t}$ production fraction via $gg$ fusion and find $f_{gg}=0.096\pm 0.039(stat.){}_{-0.062}^{+0.077}(syst.)$.

4 pages, Proceedings of Top 2014, Cannes, France, 28th Sept - 3rd Oct 2014