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arXiv · 1601.01666

Three-loop cusp anomalous dimension and a conjecture for $n$ loops

Nikolaos Kidonakis
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Abstract

I present analytical expressions for the cusp anomalous dimension in QCD through three loops in terms of elementary functions and ordinary polylogarithms. I observe interesting relations between the results at different loops and provide a conjecture for the $n$-loop cusp anomalous dimension in terms of the lower-loop results. I also present numerical results and simple approximate formulas for the cusp anomalous dimension relevant to top-quark production.

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Nikolaos Kidonakis. 2016-01-07. Three-loop cusp anomalous dimension and a conjecture for $n$ loops. https://doi.org/10.1142/s0217751x16500767

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