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arXiv 0710.0329hep-lathep-ph
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Nf=2扭曲质量QCD的轻夸克质量和赝标衰变常数

Light quark masses and pseudoscalar decay constants from Nf=2 twisted mass QCD

Vittorio Lubicz, Silvano Simula, Cecilia Tarantino

摘要:

本文介绍了ETM协作组最近用Nf=2的动力学费米子进行的格点量子色动力学计算的上下夸克和奇异夸克的平均质量以及轻介子赝标衰变常数的结果。模拟是在一个单一的晶格间距值与扭曲的质量费米子作用在最大扭曲,这保证了自动O(a)-改善的物理量。夸克质量通过非微扰的RI-R重正化过程被重正化。结果表明,轻夸克质量为m_{ud} ^{MSbar}(2 Gev)=3.85 ± 0.12 ± 0.40 MeV,m_s^{MSbar}(2 Gev)=105 ± 3 ± 9 MeV,m_s/ m_{ud} =27.3 ± 0.3 ± 1.2.我们还得到了f_K=161.7 ± 1.2 ± 3.1 MeV,f_K/f_pi=1.227 ± 0.009 ± 0.024。根据该比率,通过使用实验确定的Gamma(K -> mu {bar nu}_mu(gamma))/Gamma(pi -> mu {bar nu}_mu(gamma))和|V_{ud}|从核β衰变,我们得到|V_{us}| =0.2192(5)(45),与K_{l3}衰变和么正性约束的确定一致。

英文摘要:

We present the results of the lattice QCD calculation of the average up-down and strange quark masses and of the light meson pseudoscalar decay constants, recently performed with Nf=2 dynamical fermions by the ETM Collaboration. The simulation is carried out at a single value of the lattice spacing with the twisted mass fermionic action at maximal twist, which guarantees automatic O(a)-improvement of the physical quantities. Quark masses are renormalized by implementing the non perturbative RI-MOM renormalization procedure. Our results for the light quark masses are m_{ud}^{MSbar}(2 Gev)=3.85 +- 0.12 +- 0.40 MeV, m_s^{MSbar}(2 Gev)=105 +- 3 +- 9 MeV and m_s/m_{ud}=27.3 +- 0.3 +- 1.2. We also obtain f_K=161.7 +- 1.2 +- 3.1 MeV and the ratio f_K/f_pi=1.227 +- 0.009 +- 0.024. From this ratio, by using the experimental determination of Gamma(K -> mu {bar nu}_mu (gamma))/Gamma(pi -> mu {bar nu}_mu (gamma)) and the average value of |V_{ud}| from nuclear beta decays, we obtain |V_{us}|=0.2192(5)(45), in agreement with the determination from K_{l3} decays and the unitarity constraint.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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