Strange and charm quark contributions to the anomalous magnetic moment of the muon
Strange and charm quark contributions to the anomalous magnetic moment of the muon
复制标题
奇异夸克和粲夸克对μ子反常磁矩的贡献
DOI：
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发表时间：
2014
期刊：
影响因子：
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通讯作者：
T. Teubner
中科院分区：
文献类型：
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作者：
B. Chakraborty;C. Davies;G. Donald;R. Dowdall;J. Koponen;G. Lepage;T. Teubner
本文描述了一种利用格点QCD确定强子真空极化对μ子反常磁矩贡献的新方法。我们的方法重建的阿德勒函数，使用Pad '{e}近似，从它的衍生物在q2=0获得简单和准确的矢量电流-电流相关器在零空间动量的时刻。我们测试的方法，使用奇怪的夸克quarker大体积胶子场配置，包括上下（在物理质量），奇怪的和魅力夸克在海中的晶格间距和多个卷的多个值的影响，并显示1%的准确度是可以实现的。对于粲夸克的贡献，我们使用我们以前确定的时刻与上，下和奇怪的夸克在非常精细的晶格在海上。我们发现奇夸克真空极化对反常矩的（相关）贡献为μ=53.41（59）×10 - 10，而魅力对反常矩的（相关）贡献为acμ=14.42（39）×10 - 10。这些与非晶格方法的味道分离结果非常一致，给出了关于比较的警告。我们的方法的扩展轻夸克的贡献，从夸克线断开图是简单的。
We describe a new technique to determine the contribution to the anomalous magnetic moment of the muon coming from the hadronic vacuum polarization using lattice QCD. Our method reconstructs the Adler function, using Pad'{e} approximants, from its derivatives at q2=0 obtained simply and accurately from time-moments of the vector current-current correlator at zero spatial momentum. We test the method using strange quark correlators on large-volume gluon field configurations that include the effect of up and down (at physical masses), strange and charm quarks in the sea at multiple values of the lattice spacing and multiple volumes and show that 1% accuracy is achievable. For the charm quark contributions we use our previously determined moments with up, down and strange quarks in the sea on very fine lattices. We find the (connected) contribution to the anomalous moment from the strange quark vacuum polarization to be asμ=53.41(59)×10−10, and from charm to be acμ=14.42(39)×10−10. These are in good agreement with flavour-separated results from non-lattice methods, given caveats about the comparison. The extension of our method to the light quark contribution and to that from the quark-line disconnected diagram is straightforward.