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arXiv · 0905.2909

Double-Cut of Scattering Amplitudes and Stokes' Theorem

Pierpaolo Mastrolia
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Abstract

We show how Stokes' Theorem, in the fashion of the Generalised Cauchy Formula, can be applied for computing double-cut integrals of one-loop amplitudes analytically. It implies the evaluation of phase-space integrals of rational functions in two complex-conjugated variables, which are simply computed by an indefinite integration in a single variable, followed by Cauchy's Residue integration in the conjugated one. The method is suitable for the cut-construction of the coefficients of 2-point functions entering the decomposition of one-loop amplitudes in terms of scalar master integrals.

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Pierpaolo Mastrolia. 2009-06-22. Double-Cut of Scattering Amplitudes and Stokes' Theorem. https://doi.org/10.1016/j.physletb.2009.06.033

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