Anatomy of critical fluctuations in hadronic matter

TL;DR

This paper investigates how baryonic correlations influence net-baryon number fluctuations near critical points in dense hadronic matter, emphasizing the importance of including baryonic resonances like $
(1232)$ for interpreting heavy ion collision data.

Contribution

It introduces a detailed analysis of baryonic fluctuations using the parity doublet model, highlighting the impact of baryonic correlations and resonance inclusion on critical phenomena.

Findings

Baryonic correlations significantly affect net-baryon fluctuations.

Inclusion of $
(1232)$ resonance alters susceptibility features.

Individual baryon fluctuations do not directly mirror total net-baryon fluctuations.

Abstract

Critical phenomena in phase transitions of strongly interacting matter, governed by quantum chromodynamics, are inherently encoded in the fluctuations of conserved charges. In this work, we study the net-baryon number density fluctuations, including the lowest-lying nucleon and the baryonic resonance $\Delta(1232)$, based on the parity doublet model in the mean-field approximation. We focus on the qualitative features of the second-order susceptibility of the net-baryon number density in dense hadronic matter and how the inclusion of $\Delta(1232)$ affects it. We demonstrate that the fluctuations of the individual baryons do not necessarily reflect the total net-baryon number fluctuations at finite density, due to the non-trivial correlations between different particle species. Our results highlight the role of baryonic correlations in the interpretation of data from heavy ion collision experiments.