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arXiv · 2512.10709

Disperon QED

Yizhou Fang·Sophie Kollatzsch·Marco Rocco·Adrian Signer·Yannick Ulrich·Max Zoller
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Abstract

We present disperon QED, a method to deal with data input in loop processes in Monte Carlo codes. It relies on dispersion relations, automated tools such as OpenLoops, effective field theory methods and a threshold subtraction. We motivate this method and apply it to the process $ee\to\pi\pi$ in McMule to deal with hadronic vacuum polarisation insertions in two-loop contributions as well as the vector form factor of the pion within the form-factor scalar QED approximation. The generality of this method for more complicated processes is emphasised.

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Yizhou Fang, Sophie Kollatzsch, Marco Rocco, Adrian Signer, Yannick Ulrich, Max Zoller. 2025-12-11. Disperon QED. https://doi.org/10.21468/scipostphys.20.4.116

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