2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/132155We discuss non-perturbative QCD corrections to jet distributions in hadron collisions, focussing on hadronisation and underlying event contributions. Using soft gluon resummation and Monte-Carlo modelling we show that hadronisation dominates at small values of the jet radius R, behaving as 1/R, while underlying event corrections grow with the jet area. This provides a handle to disentangle them and parametrize them in terms of measurable QCD parameters, which might enjoy a degree of universality.5 pages, 1 figure. Talk presented by L. Magnea at DIS 2007, Munich, Germany, April 16-20 2007High Energy Physics - Phenomenologytext