论文标题
ALP搜索的高精度MUON衰减预测
High-precision muon decay predictions for ALP searches
论文作者
论文摘要
我们提出了对极化米歇尔衰变$μ^+ \ to e^+ν_e\barν_μ$的正电子能谱的改进的理论预测。除了在电磁耦合中对$α^2 $的临近临时订单校正外，我们还以更高的订单中的对数增强了术语。由于共线发射引起的对数包括在近代的准确性上，直至订购$α^4 $。在米歇尔频谱的端点，软光子发射会导致大的对数，这些对数被重新亮相至近代到接头的对数精度。我们将结果应用于MEG II和MU3E实验的背景下，以估计理论误差对Lepton-Flavour-Favour-violation-violation day $μ^+ \ \^+ x $对轴突样粒子$ x $的影响。
We present an improved theoretical prediction of the positron energy spectrum for the polarised Michel decay $μ^+\to e^+ ν_e\barν_μ$. In addition to the full next-to-next-to-leading order correction of order $α^2$ in the electromagnetic coupling, we include logarithmically enhanced terms at even higher orders. Logarithms due to collinear emission are included at next-to-leading accuracy up to order $α^4$. At the endpoint of the Michel spectrum, soft photon emission results in large logarithms that are resummed up to next-to-next-to-leading logarithmic accuracy. We apply our results in the context of the MEG II and Mu3e experiments to estimate the impact of the theory error on the branching ratio sensitivity for the lepton-flavour-violating decay $μ^+\to e^+ X$ of a muon into an axion-like particle $X$.
