arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2209.14367hep-phnucl-th
收藏

对QCD迹线反常的夸克和胶子分解的三圈修正及其应用

Three-loop corrections to the quark and gluon decomposition of the QCD trace anomaly and their applications

Kazuhiro Tanaka

摘要:

在QCD能量动量张量$T^{μν}$中,对物理矩阵元有贡献的项表示为规范不变夸克部分和胶子部分之和。由于夸克和胶子之间的相互作用,每个部分都经历了重整化,尽管由于能量守恒和动量守恒,总张量$T^{μν}$没有被重整化。我们表明,通过重整化,每个$T^{μν}$的夸克和胶子部分收到一定量的异常的痕迹贡献,使他们的总和再现著名的QCD痕迹异常。我们给出了在微扰理论中导出每个夸克/胶子部分对所有阶的反常迹贡献的方法,并在维数正则化的$\overline{\rm MS}$方案中得到了相应的三圈阶的显式公式.我们应用我们的三圈夸克/胶子迹反常分解公式来计算反常引起的核子和π介子的质量结构。我们的三圈公式的另一个应用是对核子$\bar{C}_{q,g}$的扭四引力形状因子的约束的定量分析。

英文摘要:

In the QCD energy-momentum tensor $T^{μν}$, the terms that contribute to physical matrix elements are expressed as the sum of the gauge-invariant quark part and gluon part. Each part undergoes the renormalization due to the interactions among quarks and gluons, although the total tensor $T^{μν}$ is not renormalized thanks to conservation of energy and momentum. We show that, through the renormalization, each of the quark and gluon parts of $T^{μν}$ receives a definite amount of anomalous trace contribution, such that their sum reproduces the well-known QCD trace anomaly. We provide a procedure to derive such anomalous trace contribution for each quark/gluon part to all orders in perturbation theory, and obtain the corresponding explicit formulas up to three-loop order in the $\overline{\rm MS}$ scheme in the dimensional regularization. We apply our three-loop formulas of the quark/gluon decomposition of the trace anomaly to calculate the anomaly-induced mass structure of nucleons as well as pions. Another application of our three-loop formulas is a quantitative analysis for the constraints on the twist-four gravitational form factors of the nucleon, $\bar{C}_{q,g}$.

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。

↑