2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/202104Intrinsic differences in the processes involved in the development of electromagnetic and hadronic showers in the atmosphere have been evidenced by means of a careful analysis of the event image given by the ARGO-YBJ detector. The images have been analyzed at different length scales and their multifractal nature has been studied. The use of the multiscale approach together with a properly designed and trained Artificial Neural Network, allowed us to obtain a good gamma/hadron discrimination power. If confirmed by further studies on different event cathegories, this result would allow to nearly double the detector sensitivity to gamma ray sources.10 pages, 5 figures, Presented at the "Incontro Nazionale di Astrofisica delle Alte Energie", Rome 15-16 May 2003Astrophysicstext