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arXiv · 0801.2237

Full one-loop amplitudes from tree amplitudes

Walter T. Giele·Zoltan Kunszt·Kirill Melnikov
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Abstract

We establish an efficient polynomial-complexity algorithm for one-loop calculations, based on generalized $D$-dimensional unitarity. It allows automated computations of both cut-constructible {\it and} rational parts of one-loop scattering amplitudes from on-shell tree amplitudes. We illustrate the method by (re)-computing all four-, five- and six-gluon scattering amplitudes in QCD at one-loop.

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Walter T. Giele, Zoltan Kunszt, Kirill Melnikov. 2008-01-15. Full one-loop amplitudes from tree amplitudes. https://doi.org/10.1088/1126-6708%2F2008%2F04%2F049

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