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Non-perturbative chiral approach to Kp -->gamma Y reactions

T. -S. H. Lee·J. A. Oller·E. Oset·A. Ramos
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Abstract

A recently developed nonperturbative chiral approach to describe the S=-1 meson-baryon reactions has been extended to investigate the near threshold $K^- p \to γΛ, γΣ^0$ reactions. With the parameters governed by chiral SU(3) symmetry, we show that the predicted branching ratios $Γ_{K^- p \to γΛ}/Γ_{K^- p \to all}$ and $Γ_{K^-p\to γΣ^0}/Γ_{K^- p \to all}$ are close to the experimental values. The coupling with the $η$ channels, which was shown to be important in the $S=-1$ meson-baryon reactions, is also found to be significant here. Our results are consistent with the interpretation of the $Λ(1405)$ as a quasi-bound meson-baryon state as found in other similar chiral approaches.

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T. -S. H. Lee, J. A. Oller, E. Oset, A. Ramos. 1998-09-11. Non-perturbative chiral approach to Kp -->gamma Y reactions. https://doi.org/10.1016/s0375-9474(98)00581-8

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