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Journal of High Energy Physics

, 2014:76 | Cite as

Light fermionic NNLO QCD corrections to top-antitop production in the quark-antiquark channel

  • Gabriel Abelof
  • Aude Gehrmann-De Ridder
Open Access
Regular Article - Theoretical Physics

Abstract

We present the NNLO corrections to top pair production in the quark-antiquark channel proportional to the number of light quark flavors N l . While the double real corrections were derived previously, here we compute the real-virtual and virtual-virtual contributions in this partonic channel. Using the antenna subtraction formalism, we show that the subtraction terms correctly approximate the real-virtual contributions in all their infrared limits. Combined with the integrated forms of the double real and real-virtual subtraction terms, we show analytically that the explicit infrared poles cancel at the real-virtual and virtual-virtual levels respectively, thereby demonstrating the validity of the massive extension of the NNLO antenna formalism. These NNLO corrections are implemented in a Monte Carlo parton level generator providing full kinematical information on an event-by event basis. With this program, NNLO differential distributions in the form of binned histograms are obtained and presented here.

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

  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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