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Loop Amplitudes in Pure Yang-Mills from Generalised Unitarity

Andreas Brandhuber·Simon McNamara·Bill Spence·Gabriele Travaglini
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Abstract

We show how generalised unitarity cuts in D = 4 - 2 epsilon dimensions can be used to calculate efficiently complete one-loop scattering amplitudes in non-supersymmetric Yang-Mills theory. This approach naturally generates the rational terms in the amplitudes, as well as the cut-constructible parts. We test the validity of our method by re-deriving the one-loop ++++, -+++, --++, -+-+ and +++++ gluon scattering amplitudes using generalised quadruple cuts and triple cuts in D dimensions.

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Andreas Brandhuber, Simon McNamara, Bill Spence, Gabriele Travaglini. 2005-06-09. Loop Amplitudes in Pure Yang-Mills from Generalised Unitarity. https://doi.org/10.1088/1126-6708%2F2005%2F10%2F011

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