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تسجيل مستخدم جديدScalar-Meson - Baryon Coupling Constants in QCD Sum Rules
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The external-field QCD Sum Rules method is used to evaluate the coupling constants of the light-isoscalar scalar meson (``sigma or epsilon) to the Lambda, Sigma, and Xi baryons. 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 alpha_s equiv F/(F+D)=0.55. The coupling constants with SU(3) breaking effects are also discussed.
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