Noncongruence of phase transitions in strongly interacting matter

TL;DR

This paper explores the unique characteristics of noncongruent first-order phase transitions in strongly interacting matter, highlighting differences in phase diagram features and comparing QCD and nuclear liquid-gas transitions.

Contribution

It provides a detailed comparison of noncongruent phase transitions in QCD and nuclear matter, emphasizing their distinct behaviors and phase diagram features.

Findings

QCD and nuclear liquid-gas phase transitions have opposite slopes in the pressure-temperature plane.

Noncongruent PTs exhibit different dimensionalities of phase diagrams and locations of critical points.

Distinct features are identified in symmetric and asymmetric matter in heavy-ion collisions and neutron stars.

Abstract

First-order phase transitions (PTs) with more than one globally conserved charge, so-called noncongruent PTs, have characteristic differences compared to congruent PTs (e.g., dimensionality of phase diagrams and location of critical points and endpoints). Here we discuss the noncongruent features of the QCD PT and compare it with the nuclear liquid-gas (LG) PT, for symmetric and asymmetric matter in heavy-ion collisions and neutron stars. In addition, we have identified a principle difference between the LG and the QCD PT: they have opposite slopes in the pressure-temperature plane.