标题： 弱包容衰变中的预渐近效应理论 显示英文标题

标题： Theory of Pre-Asymptotic Effects in Weak Inclusive Decays

摘要： 我基于系统性的 OPE/HQET 展开，在重夸克质量为 $m_Q$ 的 $1/m_Q$ 中介绍了预渐近效应的理论。这一思想通过两个最具启发性的例子来解释，并强调了教育学方面的内容。回顾了去年的一些重要结果。 在讨论夸克-强子对偶性问题时，这是该理论的基本组成部分之一，我证明了算符乘积展开 {\em 本身} 是一个渐近展开。这个展开中高阶项的行为决定了对偶性的开始以及对偶关系的准确性。 OPE 中高阶项的因子发散意味着在 $\alpha_s$ 平面中有复杂的解析结构，包含类型为 $\exp [-\exp (1/\alpha_s )]$ 的项。 显示英文摘要

摘要： I give an introduction to the theory of preasymptotic effects based on the systematic OPE/HQET expansion in $1/m_Q$ where $m_Q$ is the heavy quark mass. The general idea is explained in two most instructive examples, with an emphasis on pedagogical aspects. Some important results of the last year are reviewed. In discussing the issue of the quark-hadron duality, one of the basic ingredients of the theory, I prove that the operator product expansion {\em per se} is an asymptotic expansion. The behavior of the high order terms in this expansion determines the onset of duality and the accuracy of the duality relations. The factorial divergence of the high-order terms in OPE implies a sophisticated analytical structure in the $\alpha_s$ plane, with terms of the type $\exp [-\exp (1/\alpha_s )]$.