DEEP-INELASTIC SPIN AND FLAVOR ASYMMETRY OF THE NUCLEON FROM A QCD-INSPIRED QUARK-MODEL

A systematic procedure is described which permits the structure functi ons of nucleons to be calculated from a nonrelativistic constituent qu ark model. Transformation from the nucleon rest frame to the light con e or infinite momentum frame is accomplished based on work of Susskind , which does not require the weak binding and nonrelativistic kinemati cal approximations used in previous work. The light-cone distribution functions so obtained are then subjected to QCD evolution, giving pred ictions for the quark momentum densities. The model incorporates SU(6) breaking by the QCD-inspired one gluon exchange potential originated by De Rujula, Georgi, and Glashow, with the parameters fixed by Isgur and Karl from the N-Delta mass splitting. In contrast with some previo us work, the parameter values which fit the baryon mass spectrum are h ere shown to also give rather good agreement with the deep-inelastic f lavor and spin asymmetries in the Valence region.