Spin Asymmetries In Proton-Proton Scattering At High Energies And   Moderately Large Momentum Transfer
  We study $pp$ scattering at high energies and moderately large momentum transfer using a QCD--based model in which the proton is viewed as being composed of a quark and a diquark. This model leads to spin asymmetries which are neither small nor vanish at high energies. The predicted ratio of helicity flip and non-flip amplitudes is about 0.2-0.3 and $A_n$ asymmetry is about 20-30% for $|t| > 4 {GeV}^2$. 
S.V.Goloskokov