Spin of ground state baryons

We calculate the quark spin contribution to the total angular momentum of flavor octet and flavor decuplet ground state baryons using a spin-flavor symmetry based parametrization method of quantum chromodynamics. We find that third order SU(6) symmetry breaking three-quark operators are necessary to explain the experimental result {Sigma}{sub 1}=0.29(09). For spin 3/2 decuplet baryons, we predict that the quark spin contribution is {Sigma}{sub 3}=3.93(22), i.e. considerably larger than their total angular momentum.