Azimuthal asymmetries in deep inelastic scattering

Using the recent experimental data on the left–right asymmetry in fragmentation of transversely polarized quarks and the theoretical calculation of the proton transversity distribution in the effective chiral quark–soliton model we explain the azimuthal asymmetries in semi-inclusive hadron production on longitudinally (HERMES) and transversely (SMC) polarized targets with no free parameters. On this basis we state that the proton transversity distribution could be successfully measured in future DIS experiments with longitudinally polarized target.