Figure 2

Top panels: collision centrality evolution of the longitudinal (left) and azimuthal (right) widths of the $G_{2}$ CD and CI correlators measured in Pb--Pb collisions at $\sqrt{s_{\rm{NN}}} = 2.76\;\text{\TeVe}$. Central and bottom panels: width evolution relative to the value in the most peripheral collisions of the two-particle transverse momentum correlations $G_{2}^{\rm CI}$ (central) and $G_{2}^{\rm CD}$ (bottom) along the longitudinal (left) and azimuthal (right) dimensions. Data are compared with HIJING and AMPT model expectations. In data, vertical bars and shaded bands represent statistical and systematic uncertainties, respectively. For models, shaded bands represent statistical uncertainties.