System Size and Centrality Dependence of the Balance Function in A + A Collisions at s(NN)^(1/2) = 17.2 GeV

TL;DR

This study investigates how the size and centrality of heavy-ion collisions at 17.2 GeV affect charge correlations, revealing that larger and more central collisions lead to narrower balance functions, possibly indicating delayed hadronization.

Contribution

It provides the first systematic analysis of the system size and centrality dependence of the balance function at SPS energies using the NA49 detector.

Findings

Balance function width decreases with system size and centrality.

Narrower balance functions suggest delayed hadronization in central collisions.

Results support the hypothesis of longer hadronization times in larger systems.

Abstract

Electric charge correlations were studied for p+p, C+C, Si+Si and centrality selected Pb+Pb collisions at $\sqrt{s_{NN}} = 17.2$ GeV with the NA49 large acceptance detector at the CERN-SPS. In particular, long range pseudo-rapidity correlations of oppositely charged particles were measured using the Balance Function method. The width of the Balance Function decreases with increasing system size and centrality of the reactions. This decrease could be related to an increasing delay of hadronization in central Pb+Pb collisions.