Journal of High Energy Physics

, 2018:62 | Cite as

Factorisation and subtraction beyond NLO

  • L. MagneaEmail author
  • E. Maina
  • G. Pelliccioli
  • C. Signorile-Signorile
  • P. Torrielli
  • S. Uccirati
Open Access
Regular Article - Theoretical Physics


We provide a general method to construct local infrared subtraction counterterms for unresolved radiative contributions to differential cross sections, to any order in perturbation theory. We start from the factorised structure of virtual corrections to scattering amplitudes, where soft and collinear divergences are organised in gauge-invariant matrix elements of fields and Wilson lines, and we define radiative eikonal form factors and jet functions which are fully differential in the radiation phase space, and can be shown to cancel virtual poles upon integration by using completeness relations and general theorems on the cancellation of infrared singularities. Our method reproduces known results at NLO and NNLO, and yields substantial simplifications in the organisation of the subtraction procedure, which will help in the construction of efficient subtraction algorithms at higher orders.


QCD Phenomenology Jets 


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Copyright information

© The Author(s) 2018

Authors and Affiliations

  • L. Magnea
    • 1
    Email author
  • E. Maina
    • 1
  • G. Pelliccioli
    • 1
  • C. Signorile-Signorile
    • 1
  • P. Torrielli
    • 1
  • S. Uccirati
    • 1
  1. 1.Dipartimento di Fisica and Arnold-Regge CenterUniversità di Torino and INFN, Sezione di TorinoTorinoItaly

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