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arXiv · 1812.09001

Form factor recursion relations at loop level

Lorenzo Bianchi·Andreas Brandhuber·Rodolfo Panerai·Gabriele Travaglini
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Abstract

We introduce a prescription to define form factor integrands at loop level in planar $\mathcal{N}=4$ supersymmetric Yang-Mills theory. This relies on a periodic kinematic configuration that has been instrumental to describe form factors at strong coupling in terms of periodic Wilson loops. With this prescription, we are able to formulate loop-level recursion relations for planar form factor integrands, using a two-line (BCFW) and an all-line shift. We also point out important differences with the known recursion relations of integrands of planar loop amplitudes. We present a number of concrete one-loop examples to illustrate and validate our prescription for form factor integrands.

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Lorenzo Bianchi, Andreas Brandhuber, Rodolfo Panerai, Gabriele Travaglini. 2018-12-21. Form factor recursion relations at loop level. https://doi.org/10.1007/jhep02(2019)182

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