Holomorphic Anomaly Of Unitarity Cuts And One-Loop Gauge Theory Amplitudes
نویسنده
چکیده
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-toMHV 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 An;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.
منابع مشابه
Computing One-Loop Amplitudes From The Holomorphic Anomaly Of Unitarity Cuts
We propose a systematic way to carry out the method introduced in hep-th/0410077 for computing certain unitarity cuts of one-loop N = 4 amplitudes of gluons. We observe that the class of cuts for which the method works involves all next-to-MHV ngluon one-loop amplitudes of any helicity configurations. As an application of our systematic procedure, we obtain the complete seven-gluon one-loop lea...
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