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arXiv · 1909.10244

A subtraction scheme for massive QED

T. Engel·A. Signer·Y. Ulrich
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Abstract

We present an extension of the FKS subtraction scheme beyond next-to-leading order to deal with soft singularities in fully differential calculations within QED with massive fermions. After a detailed discussion of the next-to-next-to-leading order case, we show how to extend the scheme to even higher orders in perturbation theory. As an application we discuss the computation of the next-to-next-to-leading order QED corrections to the muon decay and present differential results with full electron mass dependence.

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T. Engel, A. Signer, Y. Ulrich. 2019-09-23. A subtraction scheme for massive QED. https://doi.org/10.1007/jhep01(2020)085

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