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arXiv · hep-ph/0105093

Vacuum Saturation Hypothesis and QCD Sum Rules

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

The accuracy of the vacuum saturation hypothesis is discussed using the examples of vacuum expectation values of four-quark operators and the parameter $B$, which determines the short-distance contribution to the $K^0 - \bar K^0$ mixing. Note added: The approach based on sum rules in position (x-)space as elaborated in the paper is relevant and useful tool for the current phenomenology. In particular, it provides the unique possibility of direct non-perturbative estimation of the VEV's of four-quark operators renormalized in any scheme, including the MSbar one.

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K. G. Chetyrkin, A. A. Pivovarov. 2001-05-10. Vacuum Saturation Hypothesis and QCD Sum Rules. https://doi.org/10.1007/bf02789008

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