Collision system size dependence of dihadron azimuthal correlations in ultra-relativistic heavy ion collisions

TL;DR

This study uses a multi-phase transport model to analyze how dihadron azimuthal correlations depend on system size in ultra-relativistic heavy ion collisions, revealing size-dependent structures and potential signals of deconfinement onset.

Contribution

It demonstrates that correlation structures and yields depend on system size, with double-peak formations only in larger collision systems, offering insights into QCD phase transition signals.

Findings

Correlation function structures depend on system size.

Double-peak structures only appear in large systems.

Correlation parameters increase with system size.

Abstract

The system size dependence of dihadron azimuthal correlations in ultra-relativistic heavy ion collision is simulated by a multi-phase transport model. The structure of correlation functions and yields of associated particles show clear participant path-length dependences in collision systems with a partonic phase. The splitting parameter ($D$) and Root Mean Square Width ($\Delta \phi_{rms}$) of away side correlation functions increase with collision system size from $^{14}$N+$^{14}$N to $^{197}$Au+$^{197}$Au collisions. The double-peak structure of away side correlation functions can only be formed in sufficient "large" collision systems. These properties provide some hints to study onset of deconfinement, which is related to the QCD phase boundary and QCD critical point, by an energy-size scan.