2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/226967The event-by-event p_T-fluctuations in proton-proton and central Pb-Pb collisions, which have been experimentally studied by means of the so-called Phi-measure, are analyzed. The contribution due to the correlation which couples the average p_T to the event multiplicity is computed. The correlation appears to be far too weak to explain the preliminary experimental value of Phi (p_T) in p-p interactions. The significance of the result is discussed.5 pages, 2 figures, minor improvementsNuclear TheoryHigh Energy Physics - PhenomenologyNuclear Experimenttext