Centrality dependence of hadronization and chemical freeze-out   conditions in heavy ion collisions at \sqrt s_{NN} = 2.76 TeV
  We present an analysis of hadronic multiplicities measured in Pb-Pb collisions at \sqrt s_{NN} = 2.76 TeV as a function of the collision centrality within the statistical hadronization model. Evidence is found of a dependence of the chemical freeze-out temperature as a function of centrality, with a slow rise from central to peripheral collisions, which we interpret as an effect of post-hadronization inelastic scatterings. Using correction factors calculated by means of a simulation based on the UrQMD model, we are able to obtain a significant improvement in the statitical model fit quality and to reconstruct the primordial chemical equilibrium configuration. This is characterized by a nearly constant temperature of about 164 MeV which we interpret as the actual hadronization temperature. 
F. Becattini (U. Florence), M. Bleicher (FIAS Frankfurt), E. Grossi   (U. Florence), J. Steinheimer (FIAS, Frankfurt), R. St...
nucl-th hep-ph