On the factorization of overlapping singularities at NNLO

  • Charalampos Anastasiou
  • Franz Herzog
  • Achilleas Lazopoulos


Real and virtual corrections in NNLO QCD require multi-dimensional integrals with overlapping singularities. We first review ideas and methods which have been proposed for performing such computations. We then present a new method for the factorization of overlapping singularities based on non-linear integral transformations. We apply this method for the evaluation of all integral topologies which appear in double real radiation corrections in cross-section calculations for the production of a heavy system at hadron colliders. Finally, we demonstrate with typical examples that two-loop virtual corrections are amenable to the same method.


NLO Computations QCD 


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Copyright information

© SISSA, Trieste, Italy 2011

Authors and Affiliations

  • Charalampos Anastasiou
    • 1
  • Franz Herzog
    • 1
  • Achilleas Lazopoulos
    • 1
  1. 1.Institute for Theoretical PhysicsETH ZurichZurichSwitzerland

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