Fluctuation of strongly interacting matter in Polyakov Nambu Jona-Lasinio model in finite volume

TL;DR

This study investigates how susceptibilities of conserved charges in strongly interacting matter vary with system size and temperature, revealing volume scaling in different phases and its breakdown near the cross-over, aiding understanding of freeze-out conditions.

Contribution

It introduces a volume-dependent analysis of susceptibilities in the Polyakov Nambu Jona-Lasinio model, highlighting their behavior across phase transitions in finite systems.

Findings

Susceptibilities scale with volume in hadronic and partonic phases.

Scaling breaks down near the cross-over temperature range.

Measurements of susceptibilities can indicate proximity to the cross-over in heavy-ion collisions.

Abstract

We have estimated the susceptibilities of conserved charges for 2-flavor strongly interacting matter with varying system sizes, using the Polyakov loop enhanced Nambu Jona-Lasinio model. The susceptibilities for vanishing baryon densities are found to show a scaling with the system volume in the hadronic as well as partonic phase. This scaling breaks down for a temperature range of about 30-50 MeV around the cross-over region. Simultaneous measurements of the various susceptibilities may thus indicate how close to the cross-over region the freeze-out occurs for the fireball created in heavy-ion collision experiments.