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تسجيل مستخدم جديدThree-body hadronic structure of low-lying $1/2^+$ $Sigma$ and $Lambda$ resonances
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We discuss the dynamical generation of some low-lying $1/2^+$ $Sigma$s and $Lambda$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 $1/2^-$ $Lambda$(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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