Dynamical generation of $J^P=3/2-$ resonances and the $\Lambda (1520)$ resonance

Abstract

The lowest order chiral Lagrangian is used to study s-wave interactions of the baryon decuplet with the octet of pseudoscalar mesons. The coupled channel Bethe Salpeter equation is used to obtain dynamically generated ${\frac{3}{2}}^{-}$ resonances in the partial wave amplitudes which provide a reasonable description to a number of 3 and 4-star resonances like $\Delta (1700)$, $\Lambda (1520)$, $\Sigma (1670)$, $\Sigma (1940)$, $\Xi (1820)$, $\Omega (2250)$ etc. The phenomenological introduction of d-wave channels in the coupled channel scheme along with the existing s-wave channels is shown to provide a much improved description of the $\Lambda (1520)$ resonance. The prediction of the absolute strength of the cross section in the reactions $K^{-}p\to \Lambda {\pi }^0{\pi }^0$ and $K^{-}p\to \Lambda {\pi }^{+}{\pi }^{-}$ provided by this scheme shows a good agreement with existing data.

Comments: Talk given at International Workshop on the Physics of Excited Baryons NSTAR05, 12-15 October 2005, Tallahassee, Florida, USA