Theory for muon-electron scattering @ 10ppm: A report of the MUonE theory initiative

MUonE实验理论

Theory for the MUonE experiment

本研究综述MUonE实验的理论进展，该实验通过高能μ子与原子电子的弹性散射测量类空区QED耦合跑动，以独立评估μ子反常磁矩的领头阶强子贡献，需实现10 ppm的截面计算精度并构建含本底过程的遍举蒙特卡洛产生器。

使用McMule在NNLO下的μ子-电子散射

Muon-electron scattering at NNLO with McMule

本文讨论在McMule框架中实现e μ→e μ的NNLO QED修正蒙特卡洛积分器，为MUonE实验提供红外安全微分结果，并揭示超越NNLO修正的需求。

Muon-Electron Scattering at NNLO

This thesis provides a pedagogical overview of the theoretical foundations of the McMule framework, a Monte Carlo integrator for processes with muons and other leptons. Among other things, we show how the simple infrared structure in QED can be exploited to construct FKS$^\ell$, a subtraction scheme for soft singularities to all orders in perturbation theory. Furthermore, we present the method of massification as a solution to the problem of multi-scale integrals in the presence of large scale hierarchies. Finally, we introduce next-to-soft stabilisation as an elegant tool to stabilise the num…

Muon-electron scattering at NNLO

We present the first calculation of the complete set of NNLO QED corrections for muon-electron scattering. This includes leptonic, non-perturbative hadronic, and photonic contributions. All fermionic corrections as well as the photonic subset that only corrects the electron or the muon line are included with full mass dependence. The genuine four-point two-loop topologies are computed as an expansion in the small electron mass, taking into account both, logarithmically enhanced as well as constant mass effects using massification. A fast and stable implementation of the numerically delicate re…