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arXiv 1209.0564hep-phhep-ex
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对冻结的QCD联轴器的评论

Comment on the frozen QCD coupling

B. I. Ermolaev, M. Greco, S. I. Troyan

摘要:

冻结QCD耦合是一个常被用作有效固定耦合的参数。它应该模仿运行耦合效应和缺乏知识的α_s在红外区域。通常,冻结耦合的值是固定的,从实验数据的分析。我们提出了一种新的方法来定义这样的耦合(S)独立的实验。我们认为,有不同的冻结耦合,这是用于双(DL)和单对数(SL)近似。我们介绍了四种冻结耦合:DLA中的类时耦合(即在非单重态散射振幅和DIS结构函数中存在的耦合),我们发现近似为0.24;类空变元DLA耦合(在e+e-湮灭中,在DY过程中以及在硬运动学或反向运动学中的任何散射振幅中),其是两倍大,即0.48。我们还表明,冻结耦合SL的发展方程,如BFKL必须以较不准确的方式定义相比,DLA,我们估计这种耦合是0.1。我们对单重态和非单重态截取的估计也与文献中可用的结果非常一致。

英文摘要:

The frozen QCD coupling is a parameter often used as an effective fixed coupling. It is supposed to mimic both the running coupling effects and the lack of knowledge of alpha_s in the infrared region. Usually the value of the frozen coupling is fixed from the analysis of the experimental data. We present a novel way to define such coupling(s) independently of the experiments. We argue that there are different frozen couplings which are used in the double- (DL) and single- logarithmic (SL) Approximations. We introduce four kinds of the frozen couplings: the coupling used in DLA with a time-like argument (i.e. the coupling present in the non-singlet scattering amplitudes and DIS structure functions) which we find 0.24 approximately; the DLA coupling with a space-like argument (in e+e- -annihilation, in DY processes and in any scattering amplitude in the hard or backward kinematics) which is a factor two larger, namely 0.48. We also show that the frozen coupling in the SL evolution equations like BFKL has to be defined in a way less accurate compared to DLA, and our estimate for this coupling is 0.1. Our estimates for the singlet and non-singlet intercepts are also in a good agreement with the results available in the literature.

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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