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arXiv 1301.1399hep-phhep-ex
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用QCD求和规则分析重赝标介子的衰变常数

Analysis of the decay constants of the heavy pseudoscalar mesons with QCD sum rules

Zhi-Gang Wang

摘要:

在这篇文章中,我们重新计算了所有的真空凝聚的贡献,直到6维,特别是一个圈的夸克凝聚$α_s<\bar{q}q>$和部分单圈修正的四夸克凝聚$α_s^2<\bar{q}q>^2$,在运营商的产品展开。然后我们用QCD求和规则研究了重赝标介子$D$,$D_s$,$B$和$B_s$的质量和衰变常数,其中有两种选择:{ \bf I}通过设置$m=m(μ)$来选择$\bar{MS}$质量,并进行微扰修正直到$\mathcal{O}(α_s)$阶;{ \bf II}我们选择极质量$m$,进行微扰修正直到$\mathcal{O}(α_s^2)$阶,并将能量标度设置为重夸克极质量$μ=m_Q$。在{ \bf I}的情况下,预测$f_D=(208\pm11)\,\rm{MeV}$和$f_B=(189\pm15)\,\rm{MeV}$在不确定度内与实验数据一致,而预测$f_{D_s}=(241\pm12)\,\rm{MeV}$低于实验数据的下限$f_{D_s}=(260.0\pm5.4)\,\rm{MeV}$。在{ \bf II}的情况下,预测的$f_D=(211\pm14)\,\rm{MeV}$、$f_B=(190\pm17)\,\rm{MeV}$、$f_{D_s}=(258\pm13)\,\rm{MeV}$和$f_{D_s}/f_D=1.22\pm0.08$在不确定度范围内都与实验数据非常吻合。

英文摘要:

In this article, we recalculate the contributions of all vacuum condensates up to dimension-6, in particular the one-loop corrections to the quark condensates $α_s<\bar{q}q>$ and partial one-loop corrections to the four-quark condensates $α_s^2<\bar{q}q>^2$, in the operator product expansion. Then we study the masses and decay constants of the heavy pseudoscalar mesons $D$, $D_s$, $B$ and $B_s$ using the QCD sum rules with two choices: {\bf I} we choose the $\bar{MS}$ masses by setting $m=m(μ)$ and take perturbative corrections up to the order $\mathcal{O}(α_s)$; {\bf II} we choose the pole masses $m$, take perturbative corrections up to the order $\mathcal{O}(α_s^2)$ and set the energy-scale to be the heavy quark pole mass $μ=m_Q$. In the case of {\bf I}, the predictions $f_D=(208\pm11)\,\rm{MeV}$ and $f_B=(189\pm15)\,\rm{MeV}$ are consistent with the experimental data within uncertainties, while the prediction $f_{D_s}=(241\pm12)\,\rm{MeV}$ is below the lower bound of the experimental data $f_{D_s}=(260.0\pm5.4)\,\rm{MeV}$. In the case of {\bf II}, the predictions $f_D=(211\pm14)\,\rm{MeV}$, $f_B=(190\pm17)\,\rm{MeV}$, $f_{D_s}=(258\pm13)\,\rm{MeV}$ and $f_{D_s}/f_D=1.22\pm0.08$ are all in excellent agreements with the experimental data within uncertainties.

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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