  Excited negative parity hyperon masses are calculated in a chiral bag model
in which the pion and the kaon fields are treated as perturbations. We also
calculate the hadronic widths of $\lama$ and $\lamb$ as well as the coupling
constants of the lightest $I=0$ excited hyperon to the meson-baryon channels,
and discuss how the dispersive effects of the hadronic meson-baryon decay
channels affect the excited hyperon masses. Meson cloud corrections to the
electromagnetic decay widths of the two lightest excited hyperons into ground
states $\lamz$ and $\sigz$ are calculated within the same model and are found
to be small. Our results strengthen the argument that predictions of these
hyperon radiative decay widths provide an excellent test for various quark
models of hadrons.
