English

On the analytically-improved running coupling in QCD

High Energy Physics - Theory 2022-07-27 v1 High Energy Physics - Phenomenology

Abstract

We examine, in the `t Hooft renormalization scheme, the analytic running coupling αˉt(Q2)\bar\alpha_t(Q^2) in QCD, using the two-loop β\beta-function with positive expansion parameters β0\beta_0 and β1\beta_1. An exact integral representation is derived for this causal coupling, which is fully expressed in terms of the imaginary part of the Lambert function WW. This integral form manifestly accounts for the universal value of the infrared limit αˉt(Q2=0)=4π/β0\bar\alpha_t(Q^2=0)= 4 \pi /\beta_0.

Keywords

Cite

@article{arxiv.2205.03142,
  title  = {On the analytically-improved running coupling in QCD},
  author = {F. T. Brandt and J. Frenkel and D. G. C. McKeon and G. S. S. Sakoda},
  journal= {arXiv preprint arXiv:2205.03142},
  year   = {2022}
}

Comments

9 pages, one figure; accepted for publication in Modern Physics Letters A

R2 v1 2026-06-24T11:09:11.379Z