\ Left: Cross section of isolated photons with $20\ptg25$~\GeVc for $R=0.2$ and 0.4 as a function of the centrality class or collision system, in \PbPb and \pp collisions at \snnfive from Figs.~12 and~13 of Ref.~ Also shown is the $p_{\rm T}^{\rm Z}$-integrated cross section of \zz bosons measured by CMS ~ for \PbPb collisions at \snnfive and ATLAS~ for pp and \PbPb collisions at \snnfive. The 0--90\% centrality class for isolated photons is calculated as the \Ncoll weighted average of the other centrality classes. The dotted lines indicate the value of the 0--90\% centrality class centre for ALICE and CMS measurements and 0--100\% for the ATLAS \zz boson measurement, ``All Cen.'' interval in the figure. The last interval point in the figure is the measurement in pp collisions, only provided for ALICE isolated photons and ATLAS \zz bosons Right: \raa for isolated photons (from Fig.~16 of Ref.~) and ATLAS \zz bosons, and ratio of the CMS \zz boson cross sections in each centrality class to the one in the 0--90\% centrality class. The red solid line in peripheral centrality class 70--90\% at $\raa = 0.82$ corresponds to the expectation from the HG-PYTHIA model~. In addition, the charged hadrons \raa\ in \PbPb and \pp collisions at \snnfive with $8\pt 20$~\GeVc measured by the ALICE Collaboration~ is shown for comparison.
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