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arXiv · hep-ph/9404331

Renormalization of 4-Quark Operators and QCD-Sum Rules

L. -E. Adam·K. G. Chetyrkin
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Abstract

We compute the renormalization mismatch displayed in 1--loop approximation by classically equivalent 4-quark operators and coming from different possible definitions of the $γ_5$ matrix in dimensional regularization. The result is then employed to study the effect of the various treatments of $γ_5$ upon the size of radiative corrections to 4-quark condensates in the QCD sum rules for $ρ$ and $A_1$ mesons. We find that a fully anticommuting $γ_5$ which automatically respects non-anomalous chiral Ward-Slavnov identities leads to considerably smaller corrections and reduces theoretical uncertainty in the QCD prediction for the $τ$ hadronic decay rate.

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L. -E. Adam, K. G. Chetyrkin. 1994-04-25. Renormalization of 4-Quark Operators and QCD-Sum Rules. https://doi.org/10.1016/0370-2693(94)90528-2

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