Colangelo G, Hagelstein F, Hoferichter M, Laub L, Stoffer P
Albert Einstein Center for Fundamental Physics, Institute for Theoretical Physics, University of Bern, Sidlerstrasse 5, 3012 Bern, Switzerland.
Paul Scherrer Institut, 5232 Villigen PSI, Switzerland.
Eur Phys J C Part Fields. 2021;81(8):702. doi: 10.1140/epjc/s10052-021-09513-x. Epub 2021 Aug 6.
We reassess the impact of short-distance constraints for the longitudinal component of the hadronic light-by-light amplitude on the anomalous magnetic moment of the muon, , by comparing different solutions that have recently appeared in the literature. In particular, we analyze the relevance of the exact axial anomaly and its impact on and conclude that it remains rather limited. We show that all recently proposed solutions agree well within uncertainties on the numerical estimate of the impact of short-distance constraints on , despite differences in the concrete implementation. We also take into account the recently calculated perturbative corrections to the massless quark loop to update our estimate and outline the path towards future improvements.
我们通过比较文献中最近出现的不同解决方案，重新评估强子轻子轻子振幅纵向分量的短程约束对μ子反常磁矩(a_{\mu})的影响。特别是，我们分析了精确轴矢反常的相关性及其对(a_{\mu})的影响，并得出其影响仍然相当有限的结论。我们表明，尽管具体实现方式存在差异，但最近提出的所有解决方案在短程约束对(a_{\mu})影响的数值估计的不确定性范围内都吻合得很好。我们还考虑了最近计算的无质量夸克圈的微扰修正，以更新我们的估计，并概述了未来改进的方向。
