Universal geometrical scaling for hadronic interactions

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It is shown that defining a suitable saturation momentum Qₛ, the pₜ distributions of pp and AA collisions for any centrality and energy depend only on τ=p²ₜ/Qₛ² for pₜ<Qₛ. For different projectiles, targets and centralities, the corresponding τ-lines present small differences for τ<1. For τ>1, the higher the energy or the larger the size of the participant nuclei, the larger suppression present the respective spectra. The integrated spectrum gives a fraction of the hard multiplicity in the range from 9% for pp at 0.9 TeV to 2% for Pb-Pb central collisions at 2.76 TeV.