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arXiv · 1705.04105

Top-pair production at the LHC through NNLO QCD and NLO EW

Abstract

In this work we present for the first time predictions for top-quark pair differential distributions at the LHC at NNLO QCD accuracy and including EW corrections. For the latter we include not only contributions of ${\cal O}(α_s^2 α)$, but also those of order ${\cal O}(α_s α^2)$ and ${\cal O}( α^3)$. Besides providing phenomenological predictions for all main differential distributions with stable top quarks, we also study the following issues. 1) The effect of the photon PDF on top-pair spectra: we find it to be strongly dependent on the PDF set used -- especially for the top $p_T$ distribution. 2) The difference between the additive and multiplicative approaches for combining QCD and EW corrections: with our scale choice, we find relatively small differences between the central predictions, but reduced scale dependence within the multiplicative approach. 3) The potential effect from the radiation of heavy bosons on inclusive top-pair spectra: we find it to be, typically, negligible.

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BibTeXRIS

Michal Czakon, David Heymes, Alexander Mitov, Davide Pagani, Ioannis Tsinikos, Marco Zaro. 2017-11-15. Top-pair production at the LHC through NNLO QCD and NLO EW. https://doi.org/10.1007/jhep10(2017)186

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