Centrality bin size dependence of multiplicity correlation in central Au+Au collisions at $\sqrt{s_NN}$=200 GeV}

TL;DR

This study investigates how the size of centrality bins affects charged particle multiplicity correlations in central Au+Au collisions at 200 GeV, revealing a monotonic increase in correlation strength with bin size and a small dynamical component.

Contribution

It introduces a detailed analysis of centrality bin size effects on multiplicity correlations using a parton-hadron cascade model, highlighting the minimal dynamical correlation component.

Findings

Correlation strength increases with larger centrality bins.

Dynamical correlation is only a few percent of total correlation.

Monotonic relationship between bin size and correlation strength.

Abstract

We have studied the centrality bin size dependence of charged particle forward-backward multiplicity correlation strength in 5%, 0-5%, and 0-10% most central Au+Au collisions at $\sqrt{s_NN}}$=200 GeV with a parton and hadron cascade model, PACIAE based on PYTHIA. The real (total), statistical, and NBD (Negative Binomial Distribution) correlation strengths are calculated by the real events, the mixed events, and fitting the charged particle multiplicity distribution to the NBD, respectively. It is turned out that the correlation strength increases with increasing centrality bin size monotonously. If the discrepancy between real (total) and statistical correlation strengths is identified as dynamical one, the dynamical correlation may just be a few percent of the total (real) correlation.