PARTON POLARIZATION AND CONSTITUENT QUARKS

A systematic study of the polarized-parton distributions is presented and related to the properties of the constituent quarks. The effects o f breaking SU(6) symmetry are emphasized and the Isgur-Karl constituen t model is discussed in detail, The results on the proton, neutron and deuteron structure functions are compared with the recent experimenta l data, and the role of the gluon polarization is pointed out. The rol e of the D-state admixture in the nucleon ground state is also investi gated.