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arXiv · 0906.4523

Spin Content of Lambda in QCD Sum Rules

G. Erkol·M. Oka
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Abstract

We calculate the isoscalar axial-vector coupling constants of the Lambda hyperon using the method of QCD sum rules. A determination of these coupling constants reveals the individual contributions of the u, d and the s quarks to the spin content of Lambda. Our results for the light-quark contributions are in agreement with those from experiment assuming flavor SU(3). We also find that the flavor-SU(3)-breaking effects are small and the contributions from the u and the d quarks to the Lambda polarization are negatively polarized as in the flavor-SU(3) limit.

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G. Erkol, M. Oka. 2009-06-24. Spin Content of Lambda in QCD Sum Rules. https://doi.org/10.1103/physrevd.79.114028

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