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Updated: May 10, 2026

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Total top-quark pair-production cross section at hadron colliders through O(αS(4))
Michał Czakon1, Paul Fiedler, Alexander Mitov
1Institut für Theoretische Teilchenphysik und Kosmologie, RWTH Aachen University, D-52056 Aachen, Germany.
Abstract:
We compute the next-to-next-to-leading order (NNLO) quantum chromodynamics (QCD) correction to the total cross section for the reaction gg → tt + X. Together with the partonic channels we computed previously, the result derived in this Letter completes the set of NNLO QCD corrections to the total top pair-production cross section at hadron colliders. Supplementing the fixed order results with soft-gluon resummation with next-to-next-to-leading logarithmic accuracy, we estimate that the theoretical uncertainty of this observable due to unknown higher order corrections is about 3% at the LHC and 2.2% at the Tevatron. We observe a good agreement between the standard model predictions and the available experimental measurements. The very high theoretical precision of this observable allows a new level of scrutiny in parton distribution functions and new physics searches.
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