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Strange Quark Mass from Pseudoscalar Sum Rule with O(alpha_s^4) Accuracy

K. G. Chetyrkin·A. Khodjamirian
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Abstract

We include the new, five-loop, O(alpha_s^4) correction into the QCD sum rule used for the s-quark mass determination. The pseudoscalar Borel sum rule is taken as a study case. The OPE for the correlation function with N^4LO, O(alpha_s^4) accuracy in the perturbative part, and with dimension <= 6 operators reveals a good convergence. We observe a significant improvement of stability of the sum rule with respect to the variation of the renormalization scale after including the O(alpha_s^4) correction. We obtain the interval m_s(2 GeV)=105 \pm 6 \pm 7 MeV, which exhibits about 2 MeV increase of the central value, if the O(alpha_s^4) terms are removed.

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K. G. Chetyrkin, A. Khodjamirian. 2006-02-16. Strange Quark Mass from Pseudoscalar Sum Rule with O(alpha_s^4) Accuracy. https://doi.org/10.1140/epjc%2Fs2006-02508-8

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