We calculate the parton distributions for both polarized and unpolarized octet and decuplet baryons, using the MIT bag, dressed by mesons. We show that the hyperfine interaction responsible for the $\Delta -N$ and ${\Sigma }^0-\Lambda$ splittings leads to large deviations from $\mathrm{SU}\left(3\right)\mathrm{}$ and $\mathrm{SU}\left(6\right)\mathrm{}$ predictions. For the $\Lambda$ we find significant polarized, non-strange parton distributions which lead to a sizable $\Lambda$ polarization in polarized, semi-inclusive $\mathrm{ep}$ scattering. We also discuss the flavor symmetry violation arising from the meson cloud associated with the chiral structure of baryons.

• Received 17 February 1999

DOI:https://doi.org/10.1103/PhysRevD.60.074017