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arXiv · hep-ph/9606471

Determination of pion-baryon coupling constants from QCD sum rules

Michael C. Birse·Boris Krippa
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Abstract

We evaluate the pi-N-N, pi-Sigma-Sigma and pi-Sigma-Lambda coupling constants using QCD sum rules based on pion-to-vacuum matrix elements of correlators of two interpolating baryon fields. The parts of the correlators with Dirac structure k-slash gamma_5 are used, keeping all terms up to dimension 5 in the OPE and including continuum contributions on the phenomenological side. The ratios of these sum rules to baryon mass sum rules yield stable results with values for the couplings of g_{pi NN}=12+/-5, g_{pi Sigma Sigma}=7+/-4 and g_{pi Sigma Lambda}=6+/-3. The sources of uncertainty are discussed.

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Michael C. Birse, Boris Krippa. 1996-08-22. Determination of pion-baryon coupling constants from QCD sum rules. https://doi.org/10.1103/physrevc.54.3240

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