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NLO electroweak corrections to off-shell top-antitop production with leptonic decays at the LHC

  • Ansgar Denner
  • Mathieu Pellen
Open Access
Regular Article - Theoretical Physics

Abstract

For the first time the next-to-leading-order electroweak corrections to the full off-shell production of two top quarks that decay leptonically are presented. This calculation includes all off-shell, non-resonant, and interference effects for the 6-particle phase space. While the electroweak corrections are below one per cent for the integrated cross section, they reach up to 15% in the high-transverse-momentum region of distributions. To support the results of the complete one-loop calculation, we have in addition evaluated the electroweak corrections in two different pole approximations, one requiring two on-shell top quarks and one featuring two on-shell W bosons. While the former deviates by up to 10% from the full calculation for certain distributions, the latter provides a very good description for most observables. The increased centre-of-mass energy of the LHC makes the inclusion of electroweak corrections extremely relevant as they are particularly large in the Sudakov regime where new physics is expected to be probed.

Keywords

NLO Computations 

Notes

Open Access

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Copyright information

© The Author(s) 2016

Authors and Affiliations

  1. 1.Universität Würzburg, Institut für Theoretische Physik und AstrophysikWürzburgGermany

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