Relativistic quark-diquark model of baryons with a spin-isospin   transition interaction
  The relativistic interacting quark-diquark model of baryons, recently developed, is here extended to introduce a spin-isospin transition interaction into the mass operator. The refined version of the model is used to calculate the non strange baryon spectrum. The results are compared to the present experimental data. 
M. De Sanctis, J. Ferretti, E. Santopinto, A. Vassallo
hep-ph