2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/42882The role of intrinsic transverse momentum both in unpolarized and polarized processes is discussed. We consider inclusive cross sections for pion production in hadronic collisions and for Drell-Yan processes. We reanalyze transverse single spin asymmetries (SSA) in inclusive pion production, p(transv. polarized) p --> pion + X, in terms of Sivers effect and show its contribution to A_{UL} in semi-inclusive DIS (SIDIS).LaTeX, 5 pages, 2 ps figures, uses dis03.cls. Talk delivered by U. D'Alesio at the ``XI International Workshop on Deep Inelastic Scattering'' (DIS2003), 23-27 April, 2003, St. PetersburgHigh Energy Physics - Phenomenologytext