Forward-backward asymmetries of the heavy quark pair production in $e^+e^-$ collisions at $\mathcal{O}(\alpha_s^2)$

Long Chen

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arXiv · 2105.06213

Forward-backward asymmetries of the heavy quark pair production in $e^+e^-$ collisions at $\mathcal{O}(\alpha_s^2)$

Long Chen

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Abstract

The talk is on a computational set-up for calculating the production of a massive quark-antiquark pair in electron positron collisions to order $\alpha_s^2$ in the coupling of quantum chromodynamics (QCD) at the differential level using the antenna subtraction method. Theoretical predictions on the production of top quark pairs in the continuum, and the bottom quark pairs at the $Z$ resonance, will be discussed. In particular, we would be focusing on the order $\alpha_s^2$ QCD corrections to the heavy quark forward-backward asymmetry (AFB) in electron positron collisions. In the case of the AFB of bottom quarks at the $Z$ resonance, the QCD corrections are determined with respect to both the bottom quark axis and the thrust axis. We will also briefly discuss improvements on these QCD corrections brought by applying the optimization procedure based on the Principle of Maximum Conformality.

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Long Chen. 2021-05-13. Forward-backward asymmetries of the heavy quark pair production in $e^+e^-$ collisions at $\mathcal{O}(\alpha_s^2)$. https://arxiv.org/abs/2105.06213

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