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arXiv · 1106.0155

Colourful FKS subtraction

Stefano Frixione
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Abstract

I formulate in a colour-friendly way the FKS method for the computation of QCD cross sections at the next-to-leading order accuracy. This is achieved through the definition of subtraction terms for squared matrix elements, constructed with single colour-dressed or pairs of colour-ordered amplitudes. The latter approach relies on the use of colour flows, is exact to all orders in $N$, and is thus particularly suited to being organized as a systematic expansion in 1/N.

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Stefano Frixione. 2011-06-01. Colourful FKS subtraction. https://doi.org/10.1007/jhep09(2011)091

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