# Physics of fundamental Symmetries and Interactions - PSI2019

Oct 20 – 25, 2019
PSI
Europe/Zurich timezone

## NNLO corrections in massive QED

Oct 22, 2019, 5:34 PM
1m
Poster

### Speaker

Mr Tim Engel (Paul Scherrer Institut/Universität Zürich)

### Description

Low-energy experiments with leptons such as MEG, Mu3e, MUonE and MUSE complement the research at the high-energy frontier. However, to fully exploit the experimental data, the corresponding Standard Model background has to be known to a high accuracy. For this reason we calculate the fully differential NNLO QED corrections to the processes $\mu\rightarrow e\nu\nu$, $\mu e\rightarrow \mu e$, $\mu p \rightarrow \mu p$ and $e p\rightarrow ep$. Since small-mass effects become non-negligible at this level of precision, the leading logarithmic corrections are taken into account. The corrections due to real photon emissions are computed using FKS$^{2}$, an extension of the FKS subtraction scheme to NNLO in massive QED.

### Primary authors

Prof. Adrian Signer (Paul Scherrer Institut/Universität Zürich) Pulak Banerjee (PSI - Paul Scherrer Institut) Mr Tim Engel (Paul Scherrer Institut/Universität Zürich) Mr Yannick Ulrich (Paul Scherrer Institut/Universität Zürich)