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arXiv · 0710.5925

The nature of the Lambda(1405)

E. Oset·L. S. Geng·M. Döring
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Abstract

We present here some results supporting the nature of the $Λ(1405)$ resonance as dynamically generated from the meson baryon interaction in coupled channels and resulting from the superposition of two close-by poles. We find support for this picture in the $K^- p \to π^0 π^0 Σ^0 $ reaction, which shows a different shape than the one obtained from the $π^- p \to K^0 πΣ$ reaction. We also call the attention to the $K^- p \to γπΣ$ with $πΣ$ in the $Λ(1405)$ region, which shows a narrow peak in the calculations around 1420 MeV. We also report on recent calculations of the radiative decay of the two $Λ(1405)$ states and on reactions to obtain information on these decay modes. Finally, we present results for the $pp\to p K^+Λ(1405)$ reaction recently measured at ANKE/COSY and compare them with theoretical results.

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E. Oset, L. S. Geng, M. Döring. 2007-10-31. The nature of the Lambda(1405). https://doi.org/10.1007/978-3-540-85144-8_19

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