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Strong-Coupling Constant with Flavor Thresholds at Five Loops in the MS-bar Scheme

B. A. Kniehl·A. V. Kotikov·A. I. Onishchenko·O. L. Veretin
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Abstract

We present in analytic form the matching conditions for the strong-coupling constant alpha_s^(n_f)(mu) at the flavor thresholds to four loops in the modified minimal-subtraction scheme. Taking into account the present knowledge on the coefficient beta_4 of the Callan-Symanzik beta function of quantum chromo-dynamics, we thus derive a five-loop formula for alpha_s^(n_f)(mu) together with appropriate relationships between the asymptotic scale parameters Lambda^(n_f) for different numbers of flavors n_f.

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B. A. Kniehl, A. V. Kotikov, A. I. Onishchenko, O. L. Veretin. 2006-07-18. Strong-Coupling Constant with Flavor Thresholds at Five Loops in the MS-bar Scheme. https://doi.org/10.1103/physrevlett.97.042001

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