Figure 2

Reconstructed $\pi^0$ peak width (upper row) and position (lower row) as a function of $p_{\rm T}$ in pp collisions at $\sqrt{s}= 2.76{TeV}$ (a, d), peripheral (b, e) and central (c, f) Pb-Pb collisions at $\snn =  2.76{TeV}$ in PHOS and in the photon conversion method (PCM) compared to Monte Carlo (MC) simulations. The horizontal line in (d, e, f) indicates the nominal $\pi^0$ mass.