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Polarized double-virtual amplitudes for heavy-quark pair production

  • L. Chen
  • M. Czakon
  • R. Poncelet
Open Access
Regular Article - Theoretical Physics
  • 62 Downloads

Abstract

We present the two-loop virtual amplitudes for heavy-quark pair production in light quark-antiquark annihilation and gluon fusion channels, including full spin and color dependence. We use expansions around kinematical limits and numerical integration to obtain results for the involved master integrals. From these, we determine the renormalised infrared finite remainders of the coefficients of amplitude decompositions in terms of color and spin structures. The remainders are given in form of numerical interpolation grids supported by expansions around the production threshold and the high energy limit. Finally, we provide the spin density matrix, which encodes the heavy-quark spin correlations and is sufficient for phenomenological applications. Our results are necessary for the derivation of top-quark pair production cross sections in hadron collisions in the narrow width approximation with next-to-next-to-leading order accuracy in QCD.

Keywords

QCD Phenomenology 

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) 2018

Authors and Affiliations

  1. 1.Werner-Heisenberg-Institut, Theoretical Physics DivisionMax-Planck Institute for PhysicsMünchenGermany
  2. 2.Institute for Theoretical Particle Physics and CosmologyRWTH Aachen UniversityAachenGermany

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