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arXiv · 0805.3641

Three-body hadronic structure of low-lying $1/2^+$ $Σ$ and $Λ$ resonances

A. Martínez Torres·K. P. Khemchandani·E. Oset
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Abstract

We discuss the dynamical generation of some low-lying $1/2^+$ $Σ$'s and $Λ$'s in two-meson one-baryon systems. These systems have been constructed by adding a pion in $S$-wave to the $\bar{K} N$ pair and its coupled channels, where the $1/2^-$ $Λ$(1405)-resonance gets dynamically generated. We solve Faddeev equations in the coupled-channel approach to calculate the $T$-matrix for these systems as a function of the total energy and the invariant mass of one of the meson-baryon pairs. This squared $T$-matrix shows peaks at the energies very close to the masses of the strangeness -1, $1/2^+$ resonances listed in the particle data book.

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A. Martínez Torres, K. P. Khemchandani, E. Oset. 2008-05-23. Three-body hadronic structure of low-lying $1/2^+$ $Σ$ and $Λ$ resonances. https://doi.org/10.1140/epja%2Fi2007-10563-6

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