Constraints on the strength of first-order phase transition and its relation to nucleon mass

TL;DR

This paper explores how the strength of first-order phase transitions in neutron star matter relates to the nucleon mass origin, linking microscopic QCD physics with observable neutron star properties.

Contribution

It introduces a combined modeling approach to constrain phase transition properties and their connection to nucleon mass origin using neutron star data.

Findings

Inverse correlation between phase transition strength and chiral invariant mass.

Constraints on phase transition properties from neutron star observations.

Link between nucleon mass origin and neutron star phenomenology.

Abstract

We investigate the constraints on the strength of first-order phase transitions in neutron star matter and its relation to the origin of nucleon mass. By combining the parity doublet model for the hadronic phase, the Nambu-Jona-Lasinio model for quark matter, and the integral constraint framework for intermediate densities, we construct equation of states spanning the full density range relevant to neutron stars. Our approach systematically explores how the chiral invariant mass $m_0$ affects the allowable properties of first-order quark-hadron phase transitions. Through comparison with recent neutron star observations, we establish a inverse correlation between the allowed phase transition strength and the chiral invariant mass. Our results demonstrate a direct connection between fundamental questions about the microscopic origin of nucleon mass and macroscopic neutron star observables, providing a novel astrophysical probe of chiral dynamics and QCD physics under extreme conditions.