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Scalar-Meson - Baryon Coupling Constants in QCD Sum Rules

G. Erkol·M. Oka·Th. A. Rijken·R. G. E. Timmermans
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Abstract

The external-field QCD Sum Rules method is used to evaluate the coupling constants of the light-isoscalar scalar meson (``σ'' or ε) to the Λ, Σ, and Ξbaryons. It is shown that these coupling constants as calculated from QCD Sum Rules are consistent with SU(3)-flavor relations, which leads to a determination of the F/(F+D) ratio of the scalar octet assuming ideal mixing: we find α_s \equiv F/(F+D)=0.55. The coupling constants with SU(3) breaking effects are also discussed.

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G. Erkol, M. Oka, Th. A. Rijken, R. G. E. Timmermans. 2006-03-23. Scalar-Meson - Baryon Coupling Constants in QCD Sum Rules. https://doi.org/10.1103/physrevc.73.044009

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