System-size dependence of the charged-particle pseudorapidity density at $\sqrt{s_{\rm NN}} = 5.02$ TeV for pp, p-Pb, and Pb-Pb collisions

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.