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arXiv · 2405.08750

Lepton-Pair Scattering With an Off-Shell and an On-Shell Photon at Two Loops in Massless QED

Simone Zoia
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Abstract

I present the computation of the two-loop amplitudes for the scattering of a lepton pair with an off-shell and an on-shell photon in massless QED. We apply modern techniques developed to tackle QCD amplitudes with many scales: we express the Feynman integrals in terms of a basis of special functions, and reconstruct the amplitudes from numerical finite-field evaluations. Our results complete the amplitude-level ingredients for the N3LO predictions of electron-muon scattering needed to meet the precision target of the future MUonE experiment.

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Simone Zoia. 2024-05-14. Lepton-Pair Scattering With an Off-Shell and an On-Shell Photon at Two Loops in Massless QED. https://arxiv.org/abs/2405.08750

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