Invariant mass distribution for neutral pion candidates at intermediate (left) and high (right) transverse momenta reconstructed with both photons in the EMCal for pp and Pb$-$Pb collisions in different centrality classes at $\sqrt{s_{\rm NN}}=$ 5.02 TeV The distributions are normalized to the integral in the displayed invariant mass region to be able to compare the shapes of the invariant mass distributions and their difference in the signal-to-background ratio. The gray vertical line indicates the nominal pion mass, while vertical black and red lines indicate the reconstructed neutral pion mass in pp and central Pb$-$Pb collisions, respectively.