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arXiv · 1111.7041

A subtraction scheme for NNLO computations

Radja Boughezal·Kirill Melnikov·Frank Petriello
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Abstract

We use the known soft and collinear limits of tree- and one-loop scattering amplitudes -- computed over a decade ago -- to explicitly construct a subtraction scheme for next-to-next-to-leading order (NNLO) computations. Our approach combines partitioning of the final-state phase space together with the technique of sector decomposition, following recent suggestions in Ref. [1]. We apply this scheme to a toy example: the NNLO QED corrections to the decay of the Z boson to a pair of massless leptons. We argue that the main features of this subtraction scheme remain valid for computations of processes of arbitrary complexity with NNLO accuracy.

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Radja Boughezal, Kirill Melnikov, Frank Petriello. 2011-11-30. A subtraction scheme for NNLO computations. https://doi.org/10.1103/physrevd.85.034025

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