Elastic spin observables and proton wave function normalization at large t

We summarize the role of spin observables in testing the foundations of exclusive QCD at large t. Polarized elastic scattering experiments can shed light on fundamental properties of protons, such as helicity conservation, normalization of the wave function and structure. Specific QCD motivated predictions for the spin observables are presented, which can be tested at polarized proton beam facilities. In this paper, two kinematic regions are considered: 90 degrees c.m. at large | t | and the intermediate hard scattering regime: mp2 much-lt | t |much-lt s. Theoretical models, which predict the spin observables in these regions, are reviewed. These are compared with present elastic pp data and a program is suggested for future elastic polarized pp scattering experiments, which can be used to further our knowledge of proton structure