2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/49191We present a phenomenological approach to the description of single transverse spin asymmetries (STSA) in inclusive hadron production. It generalizes the pQCD formalism for high energies and large p_T inclusive hadron production processes, A+B -> C+X, by incorporating quark intrinsic motion in the spin dependent quark distribution and fragmentation functions. We concentrate here on spin and k_T effects in the fragmentation process of a polarized quark into the observed hadron, and give predictions for STSA in semi-inclusive deep inelastic scattering, l + p -> pion + X and gamma^* + p -> pion + X.LaTeX, 4 pages, 2 eps figures, uses epsfig.sty. Talk delivered by F. Murgia at the DESY Workshop "Polarized Protons at High Energies - Accelerator Challenges and Physics Opportunities", DESY - Hamburg, 17-20 May 1999, to appear in the proceedingsHigh Energy Physics - Phenomenologytext