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arXiv · 2110.11388

Heptagon Functions and Seven-Gluon Amplitudes in Multi-Regge Kinematics

Abstract

We compute all $2\to5$ gluon scattering amplitudes in planar $\mathcal{N}=4$ super-Yang-Mills theory in the multi-Regge limit that is sensitive to the non-trivial ("long") Regge cut. We provide the amplitudes through four loops and to all logarithmic accuracy at leading power, in terms of single-valued multiple polylogarithms of two variables. To obtain these results, we leverage the function-level results for the amplitudes in the Steinmann cluster bootstrap. To high powers in the series expansion in the two variables, our results agree with the recently conjectured all-order central emission vertex used in the Fourier-Mellin representation of amplitudes in multi-Regge kinematics. Our results therefore provide a resummation of the Fourier-Mellin residues into single-valued polylogarithms, and constitute an important cross-check between the bootstrap approach and the all-orders multi-Regge proposal.

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BibTeXRIS

Lance J. Dixon, Yu-Ting Liu, Julian Miczajka. 2021-10-21. Heptagon Functions and Seven-Gluon Amplitudes in Multi-Regge Kinematics. https://doi.org/10.1007/jhep12(2021)218

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