标题： 短距离HLbL对μ子g-2的贡献 显示英文标题

标题： Short-distance HLbL contributions to the muon g-2

摘要： 当前标准模型预测与μ子反常磁矩实验值之间的$3.7\sigma$差异可能暗示了新物理的存在。 强子光-光贡献是需要在理论方面提高精度的部分之一，一个重要步骤是推导包含四个电磁电流的该量的短距离约束。 在这里，我们推导了三个大光子环虚度和静态极限下外部第四个光子的此类短距离约束。 静态光子被视为背景场，并我们在该场存在的情况下构建了一个系统的算符乘积展开。 我们表明，无质量夸克环，即主导项，在到次次领先阶的范围内，无论是由夸克质量抑制的非微扰贡献还是未被抑制的贡献，都具有数值上的主导性。 显示英文摘要

摘要： The current $3.7\sigma$ discrepancy between the Standard Model prediction and the experimental value of the muon anomalous magnetic moment could be a hint for the existence of new physics. The hadronic light-by-light contribution is one of the pieces requiring improved precision on the theory side, and an important step is to derive short-distance constraints for this quantity containing four electromagnetic currents. Here, we derive such short-distance constraints for three large photon loop virtualities and the external fourth photon in the static limit. The static photon is considered as a background field and we construct a systematic operator product expansion in the presence of this field. We show that the massless quark loop, i.e. the leading term, is numerically dominant over non-perturbative contributions up to next-to-next-to leading order, both those suppressed by quark masses and those that are not.