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One-Loop Gauge Theory Amplitudes with an Arbitrary Number of External Legs

Z. Bern·L. Dixon·D. Dunbar·D. A. Kosower
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Abstract

We review recent progress in calculations of one-loop QCD amplitudes. By imposing the consistency requirements of unitarity and correct behavior as the momenta of two legs become collinear, we construct ansatze for one-loop amplitudes with an arbitrary number of external legs. For supersymmetric amplitudes, which can be thought of as components of QCD amplitudes, the cuts uniquely specify the amplitude.

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Z. Bern, L. Dixon, D. Dunbar, D. A. Kosower. 1994-06-13. One-Loop Gauge Theory Amplitudes with an Arbitrary Number of External Legs. https://arxiv.org/abs/hep-ph/9405248

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