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Improved QCD expansion and the problem of determination of alpha_s and the condensates from the tau decays

P. A. Raczka
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Abstract

The problem of determination of $α_{s}$ and the condensates from the moments of invariant mass distribution in the semileptonic tau decays is considered. It is investigated how the extracted values of alpha_s(m^{2}_{tau}) and the condensates are affected by the the renormalization scheme dependence of the next-to-next-to-leading order perturbative corrections to the spectral moments. A simplified approach is used, in which the nonperturbative contributions are approximated by the terms of dimension six in the SVZ expansion, which arise from the four-quark condensates. \\

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P. A. Raczka. 1997-09-17. Improved QCD expansion and the problem of determination of alpha_s and the condensates from the tau decays. https://doi.org/10.1016/s0920-5632(97)01088-8

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