Pion Content of the Nucleon in Polarized Semi-Inclusive D.I.s
  An explicit pionic component of the nucleon may be identified by measuring polarized $\Delta^{++}$ fragments produced in deep-inelastic scattering off polarized protons. The pion-exchange model predicts highly correlated polarizations of the $\Delta^{++}$ and target proton, in marked contrast with the competing diquark fragmentation process. 
W.Melnitchouk (U.Regensburg) and A.W.Thomas (U.Adelaide)