\ Isolated-photon purity (left) and efficiency (right) as a function of \ptg\ for peripheral \PbPb collisions in the 50--90\% centrality class for $R=0.2$ and $R=0.4$. The points are shown with systematic and statistical uncertainties discussed in Sect. 4 of Ref. The purity is calculated using Eq. (???), and the uncertainties are calculated by adding in quadrature all the sources shown in Fig. ??? but considering the fit variation discussed in Sect. ??? The lines in the purity plot are the result of the fit with two sigmoid functions, Eq. (???), for each cone radius The efficiency and its uncertainties are obtained as explained in Sect. 3.5 and Sect. 4 of Ref. . |  |