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arXiv · 1903.02286

On the vanishing of certain cuts or residues of loop integrals with higher powers of the propagators

Robin Baumeister·Daniel Mediger·Julia Pečovnik·Stefan Weinzierl
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Abstract

Starting from two-loops, there are Feynman integrals with higher powers of the propagators. They arise from self-energy insertions on internal lines. Within the loop-tree duality approach or within methods based on numerical unitarity one needs (among other things) the residue when a raised propagator goes on-shell. We show that for renormalised quantities in the on-shell scheme these residues can be made to vanish already at the integrand level.

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Robin Baumeister, Daniel Mediger, Julia Pečovnik, Stefan Weinzierl. 2019-03-06. On the vanishing of certain cuts or residues of loop integrals with higher powers of the propagators. https://doi.org/10.1103/physrevd.99.096023

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