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arXiv · hep-ph/9409265

Fusing Gauge Theory Tree Amplitudes Into Loop Amplitudes

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

We identify a large class of one-loop amplitudes for massless particles that can be constructed via unitarity from tree amplitudes, without any ambiguities. One-loop amplitudes for massless supersymmetric gauge theories fall into this class; in addition, many non-supersymmetric amplitudes can be rearranged to take advantage of the result. As applications, we construct the one-loop amplitudes for $n$-gluon scattering in $N=1$ supersymmetric theories with the helicity configuration of the Parke-Taylor tree amplitudes, and for six-gluon scattering in $N=4$ super-Yang-Mills theory for all helicity configurations.

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Z. Bern, L. Dixon, D. C. Dunbar, D. A. Kosower. 1994-09-09. Fusing Gauge Theory Tree Amplitudes Into Loop Amplitudes. https://doi.org/10.1016/0550-3213(94)00488-z

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