Neutral pion production at midrapidity in pp and Pb–Pb collisions at √sNN = 2.76 TeV

Abstract

Invariant yields of neutral pions at midrapidity in the transverse momentum range 0.6 < pT < 12 GeV/c measured in Pb–Pb collisions at √sNN = 2.76 TeV are presented for six centrality classes. The pp reference spectrum was measured in the range 0.4 < pT < 10 GeV/c at the same centerof-mass energy. The nuclear modification factor, RAA, shows a suppression of neutral pions in central Pb–Pb collisions by a factor of up to about 8−10 for 5 pT 7 GeV/c. The presented measurements are compared with results at lower center-of-mass energies and with theoretical calculations