论文标题
QCD参数和$ f_ {b_c} $从繁重的夸克和规则
QCD parameters and $f_{B_c}$ from heavy quark sum rules
论文作者
论文摘要
我们报告了我们最近的作品[1,2]的结果，其中我们在其中c，b Quark之间的相关性{m} _ {c，b}，gluon冷凝物<α_sg^2>和qCD耦合α_s在charmonium and-scheme中的qCD耦合α_s来自Charmonium and-scheme charmonium and the charmonium and carmonium and pospra and pottoim and potterium and potermium and pospra spectra spectra and the be b _cmeson。我们使用在μ-求解稳定点评估的相对论拉普拉斯总规则（LSR）的优化比率，其中包括较高的阶PT和D <6-8二维非扰动冷凝物校正。我们从（（伪）标量M_ {χ_{χ_{0c（0b）}} -M_ {η_{η_{C（b）}}质量分布量[1]α_s（2.85）= 0.262（9）和α_s（9.50）= 0.180（8）= 0.180（8）。魅力通道最精确的结果导致α_s（M_τ）= 0.318（15）和α_s（M_z）= 0.1183（19）（3）与世界平均水平非常吻合：α_s（m_z）= 0.1181（11）[3,4]。 （轴向 - ）向量和（伪）标量通道的全局拟合的更新结果，使用laplace和momk sum sum @ n2lo [1]与m_ {b_c} [2]中的一个拟合量 @ n2lo [1]相结合，导致新的暂定QCD QCD光谱总和（QSSR）平均值：M_C（M_C（M_C（M_C）） m_b（m_b）| _average = 4196（8）MEV。 Gluon凝结物的值<α_sg^2>从（轴向） - 矢量charmonuium通道与表1中的先前确定相结合，导致新的QSSR平均值[1]：<α_sg^2> _AVERAGE =（6.35 \ pm 0.35 \ pm 0.35）x 10^{-2^{-2} geev^ev^4。我们的结果阐明了<α_sg^2>从J/ψSUM规则的<α_sg^2>的不同估计之间的差异（明显）差异，但也显示了总规则对μ-辅助量表的选择的敏感性。作为两种二元组，我们推断出B_C-Decay常数F_ {B_C} = 371（17）MEV和F_ {B_C}（2S）<139（6）Mev。
We report results of our recent works [1,2] where we where the correlations between the c,b-quark running masses{m}_{c,b}, the gluon condensate<α_s G^2> and the QCD coupling α_s in the MS-scheme from an analysis of the charmonium and bottomium spectra and the B_c-meson mass. We use optimized ratios of relativistic Laplace sum rules (LSR) evaluated at the μ-subtraction stability point where higher orders PT and D< 6-8-dimensions non-perturbative condensates corrections are included. We obtain [1] α_s(2.85)=0.262(9) and α_s(9.50)=0.180(8) from the (pseudo)scalar M_{χ_{0c(0b)}}-M_{η_{c(b)}} mass-splittings at μ=2.85(9.50) GeV. The most precise result from the charm channel leads to α_s(M_τ)=0.318(15) and α_s(M_Z)=0.1183(19)(3) in excellent agreement with the world average: α_s(M_Z)=0.1181(11)[3,4]. Updated results from a global fit of the (axial-)vector and (pseudo)scalar channels using Laplace and Moments sum rules @ N2LO [1] combined with the one from M_{B_c} [2] lead to the new tentative QCD spectral sum rules (QSSR) average : m_c(m_c)|_average= 1266(6) MeV and m_b(m_b)|_average=4196(8) MeV. The values of the gluon condensate <α_s G^2> from the (axial)-vector charmonium channels combined with previous determinations in Table 1, leads to the new QSSR average [1]: <α_s G^2>_average=(6.35\pm 0.35)x 10^{-2} GeV^4. Our results clarify the (apparent) discrepancies between different estimates of <α_s G^2> from J/ψsum rule but also shows the sensitivity of the sum rules on the choice of the μ-subtraction scale. As a biproduct, we deduce the B_c-decay constants f_{B_c}=371(17) MeV and f_{B_c}(2S)< 139(6) MeV.
