Next-to-next-to-next-to-leading order QCD prediction for the top anti-top S-wave pair production cross section near threshold in e+ e- annihilation

TL;DR

The third-order QCD prediction for the production of top antitop quark pairs in electron-positron collisions close to the threshold in the dominant S-wave state is presented and a significant reduction of the theoretical uncertainty is observed.

Abstract

We present the third-order QCD prediction for the production of top-anti-top quark pairs in electron-positron collisions close to the threshold in the dominant S-wave state. We observe a significant reduction of the theoretical uncertainty and discuss the sensitivity to the top quark mass and width.

Figures (4)

• Figure 1: Scale dependence of the cross section near threshold. The NLO, NNLO and N$^3$LO result is shown in blue, red and black, respectively. The renormalization scale is varied between $50$ and $350$ GeV.
• Figure 2: Scale dependence (hatched area) of the N$^3$LO cross section relative to the reference prediction. Overlaid are predictions for two different values of $\Gamma_t$, again normalized to the reference prediction. See text for details.
• Figure 3: Position and height of the cross section peak at LO, NLO, NNLO and N$^3$LO. The unbounded range of the LO error bars to the right and up are due to the fact that the peak disappears for large values of the renormalization scale.
• Figure 4: Relative cross section variation when the top quark mass is changed by $\pm 50\,$ and $\pm 100\,$MeV, superimposed on the scale dependence of the N$^3$LO cross section prediction. See text for details.