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arXiv · 2211.13967

Four-dimensional differential equations for the leading divergences of dimensionally-regulated loop integrals

Johannes Henn·Rourou Ma·Kai Yan·Yang Zhang
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Abstract

We invent an automated method for computing the divergent part of Feynman integrals in dimensional regularization. Our method exploits simplifications from four-dimensional integration-by-parts identities. Leveraging algorithms from the literature, we show how to find simple differential equations for the divergent part of Feynman integrals. We illustrate the method by an application to heavy quark effective theory at three loops.

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Johannes Henn, Rourou Ma, Kai Yan, Yang Zhang. 2022-11-25. Four-dimensional differential equations for the leading divergences of dimensionally-regulated loop integrals. https://doi.org/10.1007/jhep03(2023)162

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