Spin observables in elastic proton scattering from polarized He3

We have measured the absolute cross section sigma(theta) and complete sets of spin observables A(00ij) in He-3(p,p) elastic scattering at energies of 200 and 500 MeV. The observables depend on linear combinations of six complex scattering amplitudes for the p-He-3 system and provide a severe test of current reaction models. The in-scattering plane observables (A(00mm), A(00ll), A(oolm), and A(00ml)) are all in quantitative disagreement with fully microscopic nonrelativistic optical model calculations and nonrelativistic distorted wave Born approximation calculations.