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arXiv · 1711.08449

The Sudakov form factor at four loops in maximal super Yang-Mills theory

Rutger H. Boels·Tobias Huber·Gang Yang
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Abstract

The four-loop Sudakov form factor in maximal super Yang-Mills theory is analysed in detail. It is shown explicitly how to construct a basis of integrals that have a uniformly transcendental expansion in the dimensional regularisation parameter, further elucidating the number-theoretic properties of Feynman integrals. The physical form factor is expressed in this basis for arbitrary colour factor. In the nonplanar sector the required integrals are integrated numerically using a mix of sector-decomposition and Mellin-Barnes representation methods. Both the cusp as well as the collinear anomalous dimension are computed. The results show explicitly the violation of quadratic Casimir scaling at the four-loop order. A thorough analysis concerning the reliability of reported numerical uncertainties is carried out.

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Rutger H. Boels, Tobias Huber, Gang Yang. 2017-11-22. The Sudakov form factor at four loops in maximal super Yang-Mills theory. https://doi.org/10.1007/jhep01(2018)153

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