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arXiv · 0712.2999

Towards NNLO Accuracy in the QCD Sum Rule for the Kaon Distribution Amplitude

K. G. Chetyrkin·A. Khodjamirian·A. A. Pivovarov
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Abstract

We calculate the $O(α_s)$ and $O(α_s^2)$ gluon radiative corrections to the QCD sum rule for the first Gegenbauer moment $a_1^K$ of the kaon light-cone distribution amplitude. The NNL0 accuracy is achieved for the perturbative term and quark-condensate contributions to the sum rule. A complete factorization is implemented, removing logarithms of $s$-quark mass from the coefficients in the operator-product expansion. The sum rule with radiative corrections yields $a_1^K(1 \GeV)=0.10\pm 0.04$.

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K. G. Chetyrkin, A. Khodjamirian, A. A. Pivovarov. 2007-12-18. Towards NNLO Accuracy in the QCD Sum Rule for the Kaon Distribution Amplitude. https://doi.org/10.1016/j.physletb.2008.02.031

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