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arXiv · 0807.3493

On the Cuts of Scattering Amplitudes

Pierpaolo Mastrolia
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Abstract

The use of complex analysis for computing one-loop scattering amplitudes is naturally induced by generalised unitarity-cut conditions, fulfilled by complex values of the loop variable. We report on two techniques: the cut-integration with spinor-variables as contour integrals of rational functions; and the use of the Discrete Fourier Transform to optimize the reduction of tensor-integrals to master scalar integrals.

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Pierpaolo Mastrolia. 2008-07-22. On the Cuts of Scattering Amplitudes. https://doi.org/10.1016/j.nuclphysbps.2008.09.082

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