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arXiv · 1210.6108

Production of hyperon resonances induced by kaon on a deuteron target

Abstract

The $K^- d \to πYN$reaction is theoretically studied so as to investigate the $K^{-}$-induced production of the hyperon resonances $Σ(1385)$ and $Λ(1405)$. For this purpose we take into account the p-wave amplitudes for the meson-baryon two-body scatterings as well as the s-wave amplitudes. Due to the fact that the hyperon resonances are selectively produced from the $\bar{K} N$ channel in this reaction, the $Λ(1405)$ peak appears at 1420 MeV, which implies that $Λ(1405)$ and $Σ(1385)$ could be separately seen in the missing mass spectrum of the emitted nucleon in the $K^{-} d \to n X$ reaction. The $πY$ invariant mass spectrum in this study is consistent with experimental data both for $Σ(1385)$ and $Λ(1405)$. The pion exchange contributions are also included and are found to give smooth background without distorting the peak structure of the hyperon resonances.

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J. Yamagata-Sekihara, T. Sekihara, D. Jido. 2013-01-21. Production of hyperon resonances induced by kaon on a deuteron target. https://doi.org/10.1093/ptep%2Fptt009

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