System Size and Centrality Dependence of the Electric Charge   Correlations in A+A and p+p Collisions at the SPS Energies
  The Balance Function analysis method was developed in order to study the long range correlations in pseudo-rapidity of charged particle. The final results on p+p, C+C, Si+Si and centrality selected Pb+Pb collisions at $\sqrt{s_{NN}} = 17.2$ GeV and the preliminary data at $\sqrt{s_{NN}} = 8.8$ GeV are presented. The width of the Balance Function decreases with increasing system size and centrality of the collisions. This could suggest a delayed hadronization scenario. 
NA49 Collaboration (P. Christakoglou, A. Petridis, M. Vassiliou for   the NA49 Collaboration)