论文标题
对重夸克相关器的扰动扩展的调查，以$ n_f = 0 $
Investigation of the Perturbative Expansion of Moments of Heavy Quark Correlators for $N_f=0$
论文作者
论文摘要
QCD耦合是许多可观察到的计算中必要的输入，输入参数上的参数误差可能是不确定性的主要来源。可以通过比较高阶扰动计算和晶格评估了具有沉重夸克的中间两点函数的矩，这可以提取耦合，这为扰动理论提供了高能量尺度。扰动系列的截断是重要的系统不确定性。 我们通过测量$ l = 2 \，\ text {fm} $的伪量表两点函数来报告我们尝试研究此问题的尝试。我们使用完整的扭曲，非扰动的三叶草术语和晶格间距降低至$ a = 0.015 \，\ text {fm} $，以驯服相当大的离散效果。我们的初步结果表明，尽管我们的小晶格间距和夸克质量延伸超过$ 2 \，m _ {\ text {charm}} $，高阶扰动校正或连续限制不足以控制。
The QCD-coupling is a necessary input in the computation of many observables, and the parametric error on input parameters can be a dominant source of uncertainty. The coupling can be extracted by comparing high order perturbative computations and lattice evaluated moments of mesonic two-point functions with heavy quarks, which provide a high energy scale for perturbation theory. The truncation of the perturbative series is an important systematic uncertainty. We report on our attempt to study this issue by measuring pseudo-scalar two-point functions in volumes of $L=2\, \text{fm}$ with twisted-mass Wilson fermions in the quenched approximation. We use full twist, the non-perturbative clover term and lattice spacings down to $a=0.015\,\text{fm}$ to tame the sizable discretization effects. Our preliminary results indicate that either higher order perturbative corrections or the continuum limit are not under sufficient control despite our small lattice spacings and quark masses extending beyond $2\,m_{\text{charm}}$.
