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Holomorphic Anomaly Of Unitarity Cuts And One-Loop Gauge Theory Amplitudes

Freddy Cachazo
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Abstract

We show how the holomorphic anomaly found in hep-th/0409245 can be used to efficiently compute certain classes of unitarity cuts of one-loop N=4 amplitudes of gluons. These classes include all cuts of n-gluon one-loop MHV amplitudes and of n-gluon next-to-MHV amplitudes with helicities (1+,2+,3+,4-,..., n-). As an application of this method, we present the explicit computation of the (1,2,3)-cut of the n-gluon one-loop N=4 leading-color amplitude A_{n;1}(1+,2+,3+,4-,..., n-). The answer is given in terms of scalar box functions and provides information about the corresponding amplitudes. A possible way to generalize this method to all kinds of unitarity cuts is also discussed.

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Freddy Cachazo. 2004-10-13. Holomorphic Anomaly Of Unitarity Cuts And One-Loop Gauge Theory Amplitudes. https://arxiv.org/abs/hep-th/0410077

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