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The possible $Σ^0$-$Λ$ mixing in QCD sum rules

Shi-Lin Zhu·W. -Y. P. Hwang·Ze-sen Yang
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Abstract

We calculate the on-shell $Σ^0$-$Λ$ mixing parameter $θ$ with the method of QCD sum rule. Our result is $θ(m^2_{Σ^0}) =(-)(0.5\pm 0.1)$MeV. The electromagnetic interaction is not included.

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Shi-Lin Zhu, W. -Y. P. Hwang, Ze-sen Yang. 1998-02-14. The possible $Σ^0$-$Λ$ mixing in QCD sum rules. https://doi.org/10.1103/physrevd.57.1524

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