Baikov-Lee representations of cut Feynman integrals

  • Mark Harley
  • Francesco Moriello
  • Robert M. Schabinger
Open Access
Regular Article - Theoretical Physics


We develop a general framework for the evaluation of d-dimensional cut Feynman integrals based on the Baikov-Lee representation of purely-virtual Feynman integrals. We implement the generalized Cutkosky cutting rule using Cauchy’s residue theorem and identify a set of constraints which determine the integration domain. The method applies equally well to Feynman integrals with a unitarity cut in a single kinematic channel and to maximally-cut Feynman integrals. Our cut Baikov-Lee representation reproduces the expected relation between cuts and discontinuities in a given kinematic channel and furthermore makes the dependence on the kinematic variables manifest from the beginning. By combining the Baikov-Lee representation of maximally-cut Feynman integrals and the properties of periods of algebraic curves, we are able to obtain complete solution sets for the homogeneous differential equations satisfied by Feynman integrals which go beyond multiple polylogarithms. We apply our formalism to the direct evaluation of a number of interesting cut Feynman integrals.


Scattering Amplitudes Perturbative QCD 


Open Access

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Copyright information

© The Author(s) 2017

Authors and Affiliations

  • Mark Harley
    • 1
  • Francesco Moriello
    • 1
  • Robert M. Schabinger
    • 1
  1. 1.Hamilton Mathematics Institute, School of Mathematics, Trinity College, College GreenDublin 2Ireland

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