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arXiv 0903.1696hep-phhep-lat
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极小MOM格式的强耦合及其四环化

The strong coupling and its running to four loops in a minimal MOM scheme

Lorenz von Smekal, Kim Maltman, Andre Sternbeck

摘要:

本文介绍了量子色动力学的最小动量减方案。它的定义允许强耦合仅通过确定胶子和鬼传播子来确定。在朗道规范中,这个方案已经隐含在这些传播子的早期研究中,特别是与它们在红外和相关的红外固定点中的非微扰行为有关。这里我们集中讨论它的微扰用法。我们给出了该格式的显式微扰定义,以及在一般协变规范下,它的β函数和运行耦合与4圈以下的MSbar格式的关系。我们还证明,通过考虑N_f=3的例子,在某些情况下(虽然不是所有情况),通过将该级数的MSbar耦合形式重新扩展到Minimax耦合,可以显著地改善相关微扰级数的表观收敛性,使得Minimax耦合在某些唯象应用中也具有潜在的意义。

英文摘要:

We introduce the minimal momentum subtraction (MiniMOM) scheme for QCD. Its definition allows the strong coupling to be fixed solely through a determination of the gluon and ghost propagators. In Landau gauge this scheme has been implicit in the early studies of these propagators, especially in relation to their non-perturbative behaviour in the infrared and the associated infrared fixed-point. Here we concentrate on its perturbative use. We give the explicit perturbative definition of the scheme and the relation of its beta-function and running coupling to the MSbar scheme up to 4-loop order in general covariant gauges. We also demonstrate, by considering a selection of N_f=3 examples, that the apparent convergence of the relevant perturbative series can in some (though not all) cases be significantly improved by re-expanding the MSbar coupling version of this series in terms of the MiniMOM coupling, making the MiniMOM coupling also of potential interest in certain phenomenological applications.

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。

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