Title: Computing the UV-finite electromagnetic corrections to the hadronic vacuum polarization in the muon $(g-2)$ from lattice QCD Show Chinese title

Title: 计算从格点QCD中的缪子$(g-2)$的强子真空极化中的UV有限电磁修正

Abstract: In order to reach a precision of $0.2\%$ on the hadronic vacuum polarization (HVP) contribution to the anomalous magnetic moment of the muon, $(g-2)_\mu$, such that the full Standard-Model prediction matches in precision the direct experimental measurement, it is crucial to include the leading, O($\alpha$) electromagnetic corrections to HVP. In this work, we determine an important contribution to the latter from a diagram comprised of two two-point quark-loops, connected by the internal photon and gluons. This ultraviolet-finite correction is calculated from lattice QCD using a coordinate-space formalism, where photons are treated in the continuum and infinite volume. Our result amounts to a $(-0.89\pm 0.18)\%$ correction to the leading-order HVP contribution to $(g-2)_\mu$. To overcome the worsening statistical noise at large distances, our analysis is combined with phenomenological models featuring light pseudoscalar mesons with masses below 1 GeV. In particular, our data show a very steep mass dependence as dictated by the charged pion loop. Similarly, the other diagrams appearing in the O$(\alpha)$-corrections to the HVP with the internal photon connecting two separate quark loops are also ultraviolet-finite and can be computed with the same formalism. Show Chinese abstract

Abstract: 为了达到对μ子反常磁矩的强子真空极化（HVP）贡献的$0.2\%$精度，$(g-2)_\mu$，使得整个标准模型预测的精度与直接实验测量相匹配，必须包括对HVP的主导性、O($\alpha$)电磁修正。 在本工作中，我们确定了后者的一个重要贡献，该贡献来自由两个两点夸克环组成的图，通过内部光子和胶子连接。 这个紫外有限的修正通过格点QCD使用坐标空间形式进行计算，其中光子被处理为连续和无限体积。 我们的结果是对$(g-2)_\mu$的领先阶HVP贡献的一个$(-0.89\pm 0.18)\%$修正。 为了克服远距离处统计噪声的恶化，我们的分析结合了具有低于1 GeV质量的轻赝标介子的唯象模型。 特别是，我们的数据显示出由带电π介子环决定的非常陡峭的质量依赖性。 同样，出现在O$(\alpha)$-修正中的其他与内部光子连接两个独立夸克环的图也是紫外有限的，并且可以使用相同的公式进行计算。