We present and compare the charged-particle pseudorapidity densities for pp, p-Pb, and Pb-Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV measured over a wide pseudorapidity range (${-3.5 <~\eta <~5}$), using ALICE at the Large Hadron Collider. The distributions for p-Pb and Pb-Pb collisions are determined as a function of the centrality of the collisions, while results from pp collisions are reported for inelastic events with at least one charged particle at midrapidity. The charged-particle pseudorapidity densities are, under simple and robust assumptions, transformed to charged-particle rapidity densities. This allows for the calculation and the presentation of the evolution of the width of the rapidity distributions and of a lower bound on the Bjorken energy density, as a function of the number of participants in all three collision systems. We find a decreasing width of the particle production, and roughly a ten fold increase in the energy density, as the system size grows.

Submitted to: **PLB **

e-Print: arXiv:2204.10210 | PDF | inSPIRE

CERN-EP-2022-055

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