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arXiv 1504.03017hep-ph
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从Borel QCD求和规则得到精确的衰减常数比$f_{B^*}/f_B$和$f_{B_s^*}/f_{B_s}$

Accurate decay-constant ratios $f_{B^*}/f_B$ and $f_{B_s^*}/f_{B_s}$ from Borel QCD sum rules

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

备注：
10 pages. arXiv admin note: text overlap with arXiv:1404.0293
发表信息：
Phys. Rev. D 91, 116009 (2015)
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摘要：

本文在QCD中矢量流两点关联的色散和规则的框架内，分析了美矢量介子$B^*$和$B^*_s$的衰变常数。虽然矢量介子$f_{B^*}$和$f_{B_s^*}$ $-$的衰变常数与赝标介子$f_B$和$f_{B_s}$ $-$的衰变常数类似，但由于理论参数的未知性，它们的衰变常数具有很大的不确定性，而这些不确定性在矢量与赝标衰变常数的比值中几乎完全抵消。这些比率，因此可以预测非常高的精度，由于良好的控制系统的不确定性的衰变常数后，我们的强子参数提取算法的应用程序获得。我们的最终结果为$f_{B^*}/f_B=0.944\pm0.011_{\rm OPE}\pm0.018_{\rm syst}$和$f_{B_s^*}/f_{B_s}=0.947\pm0.023_{\rm OPE}\pm0.020_{\rm syst}$。因此，$f_{B^*}/f_B$和$f_{B_s^*}/f_{B_s}$分别在2.5 $σ$和2 $σ$水平下小于1。

英文摘要：

We present our analysis of the decay constants of the beauty vector mesons $B^*$ and $B^*_s$ within the framework of dispersive sum rules for the two-point correlator of vector currents in QCD. While the decay constants of the vector mesons $f_{B^*}$ and $f_{B_s^*}$ $-$ similar to the decay constants of the pseudoscalar mesons $f_B$ and $f_{B_s}$ $-$ individually have large uncertainties induced by theory parameters not known with a satisfactory precision, these uncertainties almost entirely cancel out in the ratios of vector over pseudoscalar decay constants. These ratios may be thus predicted with very high accuracy due to the good control over the systematic uncertainties of the decay constants gained upon application of our hadron-parameter extraction algorithm. Our final results read $f_{B^*}/f_B=0.944\pm0.011_{\rm OPE}\pm0.018_{\rm syst}$ and $f_{B_s^*}/f_{B_s}=0.947\pm0.023_{\rm OPE}\pm0.020_{\rm syst}$. Thus, both $f_{B^*}/f_B$ and $f_{B_s^*}/f_{B_s}$ are less than unity at 2.5$σ$ and 2$σ$ level, respectively.

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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