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About QCD sum rules for pion-nucleon coupling

Hungchong Kim
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Abstract

We point out subtleties in the previous sum rule calculations of the $πNN$ coupling associated with using either the PV or the PS coupling schemes in modeling the phenomenological side. We propose a sum rule which is independent of the coupling schemes used and has less uncertainty in the OPE. The obtained value is $g_{πN}=9.76 \pm 2.04$ where the uncertainty mainly comes from the quark-gluon mixed condensate.

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Hungchong Kim. 1999-01-13. About QCD sum rules for pion-nucleon coupling. https://arxiv.org/abs/nucl-th/9901029

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