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Updated: Apr 18, 2026

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Top quark forward-backward asymmetry in e+ e- annihilation at next-to-next-to-leading order in QCD
1Department of Physics, Southern Methodist University, Dallas, Texas 75275-0175, USA and High Energy Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
Abstract:
We report on a complete calculation of electroweak production of top-quark pairs in e+ e- annihilation at next-to-next-to-leading order in quantum chromodynamics. Our setup is fully differential in phase space and can be used to calculate any infrared-safe observable. Especially we calculated the next-to-next-to-leading-order corrections to the top-quark forward-backward asymmetry and found sizable effects. Our results show a large reduction of the theoretical uncertainties in predictions of the forward-backward asymmetry, and allow for a precision determination of the top-quark electroweak couplings at future e+ e- colliders.
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