Pseudorapidity dependence of short-range correlations from a multi-phase transport model

TL;DR

This study uses a multi-phase transport model to analyze how short-range correlations in particle collisions vary with pseudorapidity at different energies, revealing energy-dependent shape changes linked to partonic evolution.

Contribution

It demonstrates that the pseudorapidity dependence of short-range correlations is primarily influenced by partonic evolution and hadronization, not just final particle distributions or hadronic scattering.

Findings

Short-range correlations show a central pseudorapidity trough at lower energies.

At higher energies, correlations peak at central pseudorapidity.

Hadronic scattering only slightly increases correlations, not shape changes.

Abstract

Using a multi-phase transport model (AMPT) that includes both initial partonic and hadronic interactions, we study neighboring bin multiplicity correlations as a function of pseudorapidity in Au+Au collisions at $\sqrt{s_{NN}} = 7.7-62.4$ GeV. It is observed that for $\sqrt{s_{NN}} < $19.6GeV Au+Au collisions, the short-range correlations of final particles have a trough at central pseudorapidity, while for $\sqrt{s_{NN}} > $19.6GeV AuAu collisions, the short-range correlations of final particles have a peak at central pseudorapidity. Our findings indicate that the pseudorapidity dependence of short-range correlations should contain some new physical information, and are not a simple result of the pseudorapidity distribution of final particles. The AMPT results with and without hadronic scattering are compared. It is found that hadron scattering can only increase the short-range correlations to some level, but is not responsible for the different correlation shapes for different energies. Further study shows that the different pseudorapidity dependence of short-range correlations are mainly due to partonic evolution and the following hadronization scheme.