SIMPLE-MODEL FOR DESCRIPTION OF SPIN CRISIS

It is shown that, owing to pion and kaon (eta-meson) emission during t he initial stage of evolution (from q(2) similar to M(quark)(2) to q(2 ) similar to 1 GeV2), the major fraction of the proton spin that is in itially determined by the wave function of additive quarks in the SU(6 ) model can be converted into the orbital angular momentum of pseudosc alar mesons. The results of calculations are in good agreement with ex perimental data. In the same model, violation of the Gottfried sum rul e is explained by charged-meson emission. The Gribov-Lipatov relation between the structure functions of polarized particles in e(+)e(-) ann ihilation and deep-inelastic scattering is discussed. This makes it po ssible to study experimentally the spin structure of the Lambda hypero n produced in the fragmentation of quark jets.