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Nonperturbative Power Corrections in $\barα_s(q^2)$ of Two-Loop Analytization Procedure

Aleksey I. Alekseev
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Abstract

The analytization procedure which allows one to remove nonphysical singularities of the QCD running coupling constant $\barα_s(q^2)$ in the infrared region is applied to standard as well as to iterative solutions of the two-loop renormalization group equation. Non-leading at large momentum nonperturbative contributions in $\barα_s(q^2)$ are obtained in an explicit form. The coefficients of nonperturbative contributions expansions in inverse powers of the squared Euclidean momentum are calculated. For both cases considered there appear convergent at $q^2>Λ^2$ power series of negative terms with different dependence on term numbers.

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Aleksey I. Alekseev. 1999-06-09. Nonperturbative Power Corrections in $\barα_s(q^2)$ of Two-Loop Analytization Procedure. https://arxiv.org/abs/hep-ph/9906304

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