论文标题
带有交错的费米子的Muon异常磁矩：晶格间距足够小吗？
The muon anomalous magnetic moment with staggered fermions: is the lattice spacing small enough?
论文作者
论文摘要
我们将以前的工作扩展到频率连接的部分，即$a_μ^{\ rm hvp，lqc} $，该领先订单的hadroonic-vacuum-polarize（HVP）在多个方向上使用交错效仿，对muon异常磁矩$a_μ$的贡献。我们已经收集了更多的统计数据，其晶格间距为0.06美元，$ 0.09 $和0.12 $ fm，我们添加了两个新的合奏，均为晶格间距$ 0.15 $ fm，但数量不同。增加的统计数据使我们能够大大减少$A_μ^{\ rm HVP，LQC} $的统计错误和相关的窗口数量。我们还计算当前电流相关器，从中，从中获得$a_μ^{\ rm hvp，lqc} $，以交错的手性扰动理论获得近代到临时订单（nnlo），以便我们可以纠正$a_μ^{\ rm hvp for for pion for pion and inn for for pion nnlo，for pl for pion and pl for pion and inn for pion nnlo and。味觉破坏性的效果。我们讨论了nnlo手性扰动理论对$a_μ^{\ rm hvp，lqc} $的适用性以及对窗口数量的适用性，并强调它为$a_μ^{\ rm hvp，lqc} $提供了系统的EFT方法，但对于短途或中间的窗口范围butinations note。这使得很难评估在文献中广泛考虑的标准中间距离窗口数量上的系统错误。鉴于此，我们研究了一个更长的距离窗口，为此，EFT方法应该更可靠。我们最重要的结论是，尤其是对于交错的费米子，晶格间距的新高统计计算小于$ 0.06 $ fm是必不可少的。
We extend our previous work on the light-quark connected part, $a_μ^{\rm HVP,lqc}$, of the leading order hadronic-vacuum-polarization (HVP) contribution to the muon anomalous magnetic moment $a_μ$, using staggered fermions, in several directions. We have collected more statistics on ensembles with lattice spacings of $0.06$, $0.09$ and $0.12$ fm, and we added two new ensembles, both with lattice spacing $0.15$ fm, but with different volumes. The increased statistics allow us to reduce statistical errors on $a_μ^{\rm HVP,lqc}$ and related window quantities significantly. We also calculate the current-current correlator from which $a_μ^{\rm HVP,lqc}$ is obtained to next-to-next-to-leading order (NNLO) in staggered chiral perturbation theory, so that we can correct lattice values for $a_μ^{\rm HVP,lqc}$ to NNLO for finite-volume, pion-mass mistuning and taste-breaking effects. We discuss the applicability of NNLO chiral perturbation theory to $a_μ^{\rm HVP,lqc}$ and to the window quantities, emphasizing that it provides a systematic EFT approach to $a_μ^{\rm HVP,lqc}$, but not to short- or intermediate-distance window quantities. This makes it difficult to assess systematic errors on the standard intermediate-distance window quantity that is now widely considered in the literature. In view of this, we investigate a longer-distance window, for which EFT methods should be more reliable. Our most important conclusion is that, especially for staggered fermions, new high-statistics computations at lattice spacings smaller than $0.06$ fm are indispensable.
