(top) Normalized transverse momentum correlator, $\sqrt{ \llangle \Delta p_{{\rm T}1}\Delta p_{{\rm T}2} \rrangle }$$/\llangle p_{\rm T} \rrangle $, shown as a function of the charged-particle multiplicity density, $\langle{\rm d}N_{\rm ch}/{\rm d}\eta \rangle$, measured in the pseudorapidity range $|\eta| 0.8$ in \pp collisions at \s = 5.02 TeV, \XeXe collisions at \snn = 5.44 TeV, and \PbPb collisions at \snn = 5.02 TeV; (bottom) Ratio of values of $\sqrt{ \llangle \Delta p_{{\rm T}1}\Delta p_{{\rm T}2} \rrangle }$$/\llangle p_{\rm T} \rrangle $ measured in \pp and \XeXe collisions to those observed in \PbPb collisions. Statistical and systematic uncertainties are represented by vertical bars and boxes, respectively.
Figure extracted from paper