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NNLO QCD subtraction for top-antitop production in the \( q\overline{q} \) channel

  • Gabriel Abelof
  • Aude Gehrmann-De Ridder
  • Philipp Maierhöfer
  • Stefano Pozzorini
Open Access
Article

Abstract

We present the computation of the double real and real-virtual contributions to top-antitop pair production in the quark-antiquark channel at leading colour. The \( q\overline{q} \)\( t\overline{t} g \) amplitudes contributing to the real-virtual part are computed with OpenLoops, and their numerical stability in the soft and collinear regions is found to be sufficiently high to perform a realistic NNLO calculation in double precision. The subtraction terms required at real-real and real-virtual levels are constructed within the antenna subtraction formalism extended to deal with the presence of coloured massive final state particles. We show that those subtraction terms approximate the real-real and real-virtual matrix elements in all their singular limits.

Keywords

QCD Phenomenology Hadronic Colliders 

Notes

Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.

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Copyright information

© The Author(s) 2014

Authors and Affiliations

  • Gabriel Abelof
    • 1
  • Aude Gehrmann-De Ridder
    • 2
    • 3
  • Philipp Maierhöfer
    • 3
  • Stefano Pozzorini
    • 3
  1. 1.Department of Physics & AstronomyNorthwestern UniversityEvanstonU.S.A.
  2. 2.Institute for Theoretical Physics, ETHZürichSwitzerland
  3. 3.Physics InstituteUniversity of ZürichZürichSwitzerland

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