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QCD Analysis of Inclusive $ΔS=1,2$ Transitions: The $|ΔI|=1/2$ Rule

A. Pich
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Abstract

The interplay of QCD in $ΔS=1,2$ non-leptonic weak transitions can be rigorously analyzed, at the inclusive level, by studying the 2--point functions associated with the corresponding $ΔS=1,2$ effective Hamiltonians. The next-to-leading order calculation of these correlators shows a huge ($\gsim 100\%$) gluonic enhancement of the $|ΔI|=1/2$ channel, providing a qualitative understanding of the $|ΔI|=1/2$ rule within QCD.

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A. Pich. 1994-10-04. QCD Analysis of Inclusive $ΔS=1,2$ Transitions: The $|ΔI|=1/2$ Rule. https://arxiv.org/abs/hep-ph/9410208

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