McMule -- a Monte Carlo generator for low energy processes

Abstract

McMule, a Monte Carlo for MUons and other LEptons, implements many major QED processes at NNLO (eg. $ee\to ee$, $e\hat{I}¼\to e\hat{I}¼$, $ee\to \hat{I}¼\hat{I}¼$, $\ell p\to \ell p$, $\hat{I}¼\to \hat{I}½\bar{\hat{I}}½e$) including effects from the lepton masses, making it suitable for predictions for low-energy experiments such as MUonE, CMD-III, PRad, or MUSE. Recently, McMule gained the ability to generate events at NNLO rather than just pre-defined differential distributions. To avoid negative event weights, it employs cellular resampling directly as part of the generation step which further reduces the fraction of negative weights.

6 pages, 1 figure. Contribution to the proceedings of the 22nd International Workshop on Advanced Computing and Analysis Techniques in Physics Research (ACAT), 11-15 March 2024, Stony Brook, NY