Suppression of high-pT neutral pion production in central Pb+Pb collisions at √sNN = 17.3 GeV relative to p+C and p+Pb collisions

Abstract

Neutral pion transverse momentum spectra were measured in p+C and p+Pb collisions at =17.4 GeV at midrapidity (2.3lab3.0) over the range 0.7pT3.5 GeV/c. The spectra are compared to 0 spectra measured in Pb+Pb collisions at =17.3 GeV in the same experiment. For a wide range of Pb+Pb centralities (Npart300), the yield of 0's with pT2 GeV/c is larger than or consistent with the p+C or p+Pb yields scaled with the number of nucleon-nucleon collisions (Ncoll), while for central Pb+Pb collisions with Npart350, the 0 yield is suppressed.