Complete O(αs4) QCD corrections to hadronic Z decays.
Complete O(αs4) QCD corrections to hadronic Z decays.
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DOI：
10.1103/physrevlett.108.222003
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发表时间：
2012-05
影响因子：
8.6
通讯作者：
P. Baikov;K. Chetyrkin;Johann H. Kuhn;J. Rittinger
中科院分区：
文献类型：
--
作者：
P. Baikov;K. Chetyrkin;Johann H. Kuhn;J. Rittinger
在重顶夸克质量极限下，对Z玻色子到强子衰减率的轴向单态贡献进行了α(S)(4)级的修正。结合最近完成的非单重态修正的O(α(S)(4))计算，新的结果直接将我们引向第一个完整的O(α(S)(4))预测Z玻色子的总强子衰减率。Z衰变速率中新的O(α(S)(4))项导致微扰级数的显著稳定，减小了从这些测量中提取的强耦合常数α(S)的理论不确定性，并使中心值略有移动。
Corrections of order α(s)(4) for the axial singlet contributions for the decay rate of the Z boson into hadrons are evaluated in the limit of the heavy top quark mass. Combined with recently finished O(α(s)(4)) calculations of the nonsinglet corrections, the new results directly lead us to the first complete O(α(s)(4)) prediction for the total hadronic decay rate of the Z boson. The new O(α(s)(4)) term in Z-decay rate leads to a significant stabilization of the perturbative series, to a reduction of the theory uncertainty in the strong coupling constant α(s), as extracted from these measurements, and to a small shift of the central value.