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arXiv · 1801.06084

R*-operation and five-loop calculations

B. Ruijl·F. Herzog·T. Ueda·J. A. M. Vermaseren·A. Vogt
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Abstract

We sketch how the R*-operation can be used to compute the pole terms of Feynman diagrams. We identify computational difficulties when performing five-loop calculations, and provide four solutions that drastically reduce the number of terms that are generated. Using these methods, we have computed the beta function for Yang-Mills theory with fermions, the R-ratio in electron-positron annihilation, and Higgs decays to quarks and gluons at five-loop accuracy. The results for the beta function and Higgs decay width to gluons in the heavy-top limit are briefly discussed. There is no need for six-loop extensions of these calculations in the near future.

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B. Ruijl, F. Herzog, T. Ueda, J. A. M. Vermaseren, A. Vogt. 2018-01-18. R*-operation and five-loop calculations. https://arxiv.org/abs/1801.06084

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