论文标题
双环无壳QCD操作员矩阵元素以有限术语
The Two-Loop Massless Off-Shell QCD Operator Matrix Elements to Finite Terms
论文作者
论文摘要
我们以自动化的方式将QCD中的非极化和两极分化的两个 - QCD中的无质量质量外壳矩阵元素计算为$ o（\ varepsilon）$。在这里，我们使用基于逐个部分的整合关系的任意高梅林矩和差环理论的方法。该方法还构成了计算QCD异常维度的一种方法。在相应的高阶计算中，提出的对这些操作员矩阵元件的高阶贡献出现，最多四个环。所有贡献数量均可用梅林（Mellin）的谐波和谐波和谐波质量汇总$ z $ - 空间表示。我们还与文献进行了比较。
We calculate the unpolarized and polarized two--loop massless off--shell operator matrix elements in QCD to $O(\varepsilon)$ in the dimensional parameter in an automated way. Here we use the method of arbitrary high Mellin moments and difference ring theory, based on integration-by-parts relations. This method also constitutes one way to compute the QCD anomalous dimensions. The presented higher order contributions to these operator matrix elements occur as building blocks in the corresponding higher order calculations up to four--loop order. All contributing quantities can be expressed in terms of harmonic sums in Mellin--$N$ space or by harmonic polylogarithms in $z$--space. We also perform comparisons to the literature.
