Determination of light quark masses from the electromagnetic splitting of pseudoscalar meson masses computed with two flavors of domain wall fermions
Determination of light quark masses from the electromagnetic splitting of pseudoscalar meson masses computed with two flavors of domain wall fermions
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DOI：
10.1103/physrevd.76.114508
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发表时间：
2007-08
影响因子：
5
通讯作者：
T. Blum;T. Doi;M. Hayakawa;T. Izubuchi;N. Yamada
中科院分区：
文献类型：
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作者：
T. Blum;T. Doi;M. Hayakawa;T. Izubuchi;N. Yamada
我们通过格点量子色动力学（QCD）模拟来确定轻夸克质量，该模拟包含价夸克的电磁相互作用，并以带电和中性赝标量介子质量的劈裂作为输入。介子质量是在由RBC合作组针对两种动力学畴壁费米子味生成的格点QCD组态上计算的，这些组态与通过淬火非紧致格点量子电动力学（QED）生成的QED组态相结合。发现π介子质量劈裂的电磁部分为$m_{\pi^{+}} - m_{\pi^{0}} = 4.12(21)$MeV，这里仅给出了统计误差，对于K介子也类似，为$1.443(55)$MeV。我们得到的轻夸克质量结果为$m_{u}^{MS}(2\ GeV)=3.02(27)(19)$MeV，$m_{d}^{MS}(2\ GeV)=5.49(20)(34)$MeV，以及$m_{s}^{MS}(2\ GeV)=119.5(56)(74)$MeV，其中第一个误差是统计误差，第二个误差反映了我们非微扰重整化过程中的不确定性。通过对$\pm e$求平均以在每个组合的规范场组态上精确抵消$O(e)$噪声，我们能够在实际的$\alpha = 1/137$下工作，并获得非常小的统计误差。在我们的计算中，仍然存在几种系统误差来源，包括有限体积、非零格点间距、手征外推、淬火QED和淬火奇夸克，这些误差可能比上述给出的误差更显著。我们讨论了这些系统误差以及如何减少或消除它们。
We determine the light quark masses from lattice QCD simulations incorporating the electromagnetic interaction of valence quarks, using the splittings of charged and neutral pseudoscalar meson masses as inputs. The meson masses are calculated on lattice QCD configurations generated by the RBC Collaboration for two flavors of dynamical domain-wall fermions, which are combined with QED configurations generated via quenched noncompact lattice QED. The electromagnetic part of the pion mass splitting is found to be m{sub {pi}{sup +}}-m{sub {pi}{sup 0}}=4.12(21) MeV, where only the statistical error is quoted, and similarly for the kaon, 1.443(55) MeV. Our results for the light quark masses are m{sub u}{sup MS}(2 GeV)=3.02(27)(19) MeV, m{sub d}{sup MS}(2 GeV)=5.49(20)(34) MeV, and m{sub s}{sup MS}(2 GeV)=119.5(56)(74) MeV, where the first error is statistical and the second reflects the uncertainty in our nonperturbative renormalization procedure. By averaging over {+-}e to cancel O(e) noise exactly on each combined gauge field configuration, we are able to work at physical {alpha}=1/137 and obtain very small statistical errors. In our calculation, several sources of systematic error remain, including finite volume, nonzero lattice spacing, chiral extrapolation, quenched QED, and quenched strange quark, which may be more significant than the errors quoted above. We discuss these more » systematic errors and how to reduce or eliminate them. « less