Effects of a spin-flavour dependent interaction on the baryon mass   spectrum
  The effective quark interaction in a relativistically covariant constituent quark model based on the Salpeter equation is supplemented by an extra phenomenological flavour dependent force in order to account for some discrepancies mainly in the description of excited negative parity Delta resonances. Simultaneously an improved description of some other features of the light-flavoured baryon mass spectrum and of some electromagnetic form factors is obtained. 
Michael Ronniger and Bernard Ch. Metsch
hep-ph nucl-th