The multiplicity-class dependence of $\sigma_{\Delta\eta}$ in Pb-Pb, p-Pb, and pp collisions at $\sqrt{s_{\mathrm{NN}}} = 2.76$, 5.02, and 7 TeV compared with results from various event generators in panels (a), (c), and (e). Panels (b), (d), and (f) show the relative decrease of $\sigma_{\Delta\eta}$ calculated with respect to $\sigma_{\Delta\eta}^{70-80\%}$, as a function of the multiplicity class. The transverse momentum values for both the trigger and the associated particles satisfy the condition $0.2 < \pt_{,assoc}< \pt_{,trig}< 2.0$ Gev/$c$.
| ![](https://alice-publications.web.cern.ch/sites/default/files/papers/1869/PbPbwidthInDeltaEtaLowpT-16557.png ) |