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arXiv · hep-ph/9207228

QCD Perturbation Theory at Low Energies

A. C. Mattingly·P. M. Stevenson
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Abstract

We apply the optimization procedure based on the Principle of Minimal Sensitivity to the third-order calculation of $\R$. The effective couplant remains finite, freezing to a value $α_s/π= 0.26$ at low energies. Using Poggio-Quinn-Weinberg smearing we find good agreement between theory and experiment right down to zero energy.

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A. C. Mattingly, P. M. Stevenson. 1992-07-09. QCD Perturbation Theory at Low Energies. https://doi.org/10.1103/physrevlett.69.1320

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