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arXiv · hep-ph/0211277

End-point singularities of Feynman graphs on the light cone

D. Melikhov·S. Simula
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Abstract

We show that some Lorentz components of the Feynman integrals calculated in terms of the light-cone variables may contain end-point singularities which originate from the contribution of the big-circle integral in the complex k_ plane. These singularities appear in various types of diagrams (two-point functions, three-point functions, etc) and provide the covariance of the Feynman integrals on the light-cone. We propose a procedure for calculating Feynman integrals which guarantees that the end-point singularities do not appear in the light-cone representations of the invariant amplitudes.

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D. Melikhov, S. Simula. 2003-01-27. End-point singularities of Feynman graphs on the light cone. https://doi.org/10.1016/s0370-2693(03)00124-2

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