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Low lying S=-1 excited baryons and chiral symmetry

E. Oset·A. Ramos·C. Bennhold
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Abstract

The s-wave meson-baryon interaction in the $S = -1$ sector is studied by means of coupled-channels, using the lowest-order chiral Lagrangian and the N/D method to implement unitarity. The loops are regularized using dimensional renormalization. In addition to the previously studied $Λ(1405)$, employing this chiral approach leads to the dynamical generation of two more s-wave hyperon resonances, the $Λ(1670)$ and $Σ(1620)$ states. We make comparisons with experimental data and look for poles in the complex plane obtaining the couplings of the resonances to the different final states. This allows us to identify the $Λ(1405)$ and the $Λ(1670)$ resonances with $\bar{K}N$ and $KΞ$ quasibound states, respectively.

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E. Oset, A. Ramos, C. Bennhold. 2002-01-31. Low lying S=-1 excited baryons and chiral symmetry. https://doi.org/10.1016/s0370-2693(01)01523-4

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