A Cloudy Bag Model for the S-D Wave $\Kbar-N$ System

Abstract

The cloudy quark bag model is applied to the coupled ($\Kbar N$, $\Sigma \pi$, $\Lambda \pi$) system for $S-D$ partial waves. Energy--dependent separable potentials are derived, as are new numerical algorithms for solving the coupled Lippmann-Schwinger equations. The parameters are fit to $K^-p$ scattering and reaction cross sections, branching ratios, and mass spectra from $K^-p\rightarrow \Sigma\pi\pi\pi, \Lambda\pi\pi\pi$. The $\Sigma_{P13}(1385)$ and $\Lambda_{D03}(1520)$ resonances are found to be predominately elementary bag states with considerable dressing for the $\Sigma_{P13}$. The $\Lambda_{S01}(1405)$ appears as a complicated composite systems arising from two poles.