Two-Loop Four-Fermion Scattering Amplitude in QED

R. Bonciani, A. Broggio, S. Di Vita, A. Ferroglia, M. K. Mandal, P. Mastrolia, L. Mattiazzi, A. Primo, J. Ronca, W. J. Torres Bobadilla, F. Tramontano

Publications: Contribution to journalArticlePeer Reviewed


We present the first fully analytic evaluation of the transition amplitude for the scattering of a massless into a massive pair of fermions at the two-loop level in quantum electrodynamics. Our result is an essential ingredient for the determination of the electromagnetic coupling within scattering reactions, beyond the currently known accuracy, which has a crucial impact on the evaluation of the anomalous magnetic moment of the muon. It will allow, in particular, for a precise determination of the leading hadronic contribution to the (g-2)μ in the MUonE experiment at CERN, and therefore can be used to shed light on the current discrepancy between the standard model prediction and the experimental measurement for this important physical observable.

Original languageEnglish
Article number022002
Number of pages7
JournalPhysical Review Letters
Issue number2
Publication statusPublished - 12 Jan 2022
Externally publishedYes

Austrian Fields of Science 2012

  • 103036 Theoretical physics

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